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Behind the front page/special features: Comments by film maker Donal O’Neill ‘Cereal Killers’, ‘Run on Fat’ and ‘The Big Fat Fix’

20 Aug, 16 | by BJSM

Nutrition – a BJSM blog series

BJSM Editor’s Alert & Recommendation: Do not read this if you know everything you want to know about healthy eating already .

By Donal O’Neill

New Year’s Eve 2011 was the first time I stepped off a plane in Cape Town, South Africa. With the usual carry on plus duffel in the hold combo. I looked like any other holiday maker to this spectacular destination. The laptop in my bag carried two years of research into a topic of no interest to pretty much anyone but myself – or so I thought. Bleary eyed after the overnight flight, I walked out into blazing sunshine and an even brighter African adventure.

The fact that I am still here is down to some remarkable good fortune, two very special people and a niche little movie that almost didn’t happen.

The good fortune?

NoaxesThat all started at a braai (the local term for barbeque) one evening where the topic of my research was pushed center stage courtesy of special person #1. That he wasn’t even there to kick it all off himself didn’t matter a jot. Prof Tim Noakes MD, who is just about as famous in South Africa as any of their elite athletes, had issued his first public comment on the revival of that bad boy of macronutrients – FAT.

In a moment of inspiration, I penned a note to the great man asking if he would like to participate in a documentary on the topic. Our initial exchange gave birth to my first documentary – Cereal Killers. The movie charted my own experiment with a sugar and wheat free, high natural fat diet for 28 days under the watchful medical eye of Noakes. The context was simple. My fit, former elite sportsman father had suffered a very unexpected heart attack in 2010, and I just thought to myself “How the hell did that happen… and am I next?”

As I was leaving his office after our first animated discussion, Noakes said something profound with that wicked signature smile of his.

“Let’s cause some trouble.”

So we did.

The epochal scene in Cereal Killers is of course Noakes tearing out the carb loading chapter of his endurance tome, Lore of Running. When he did so, it sparked the old athlete in me and I knew there was much, much more to this low carbohydrate story.

By the time Cereal Killers released in 2013, John Yudkin’s anti sugar epic “Pure, White and Deadly” was back in print (we had to make do with a bootlegged PDF copy for research) and the topic was at least raising eyebrows. A good sign!

The good fortune never left us really. An editing delay had opened a window of opportunity to include the brilliant Dr Peter Brukner and his low carb, World Cup winning Aussie cricketers in the movie. When World Ironman Champion (AG) Sami Inkinen saw that, he contacted me out of the blue to say he too excelled on a low carb diet. Working with the ketogenic diet pioneer Prof Stephen Phinney, he was metaphorically ripping out that chapter in Lore of Running every time he swam, biked or ran.

Run on Fat

Sami would star in our second movie – Run on Fat – and Steve Phinney crackled with wisdom, enthusiasm and knowledge throughout. The athletes were emerging – albeit slowly – as advocates of lower carb diets for myriad reasons including faster recovery, lowered inflammation and improved endurance performance.

Phinney also dropped a bombshell. When he had met Ancel Keys in the 1980s at the University of Minnesota, Keys had reached in to his briefcase and produced a paper he could not get published. That paper, which allegedly showed that high cholesterol was not as strongly associated with premature death as he originally thought, would have gone some way to amending his own – and possibly everyone else’s – position on cholesterol. “Keys was furious.” said Phinney.

When we wrapped Run on Fat, I wanted to know more about Keys, the legacy he had left and the direction he may have taken with that unpublished paper.

The answers lay in Pioppi (pop 190), a tiny Italian village two hours south of Naples which is the UNESCO protected home of the Mediterranean Diet. Keys, the most powerful voice in the history of nutrition, had lived here for 30 years. His work in Pioppi ultimately laid the foundation for the introduction of modern low fat food policies in the 1970s, but he seemingly died an angry man. Keys’s influence had waned and he was unable to find a scientific journal to publish his updated position on cholesterol. “It was too late. The juggernaut was unstoppable.” said Phinney.

British Cardiologist Dr Aseem Malhotra joined me to explore why that happened. What we found amongst these wonderful people in a magical environment, was remarkable. “We have a treasure” said Stefano Pisani, the local Mayor.  He speaks the truth. That journey is our new movie – The Big Fat Fix.

big fat fix poster movie

Men’s Health have called it “the final word in the fight against dietary misinformation.” I hope they’re right.

The adventure continues at I encourage you to check it out –

PS  Special person #2 is my wife Louise. Because every film maker needs a happy ending too.


Donal O’Neill is a former international athlete and film maker.

Will whole grains make you live longer?

22 Jul, 16 | by BJSM

Nutrition – a BJSM blog series

The mission of BJSM is to share quality content and promote debate relating to how physical activity, exercise and sport influence health. With this mission in mind, BJSM has at least 3 strong reasons to engage with content related to nutrition:

  1.  Sports medicine has long been closely associated with nutrition – nutrition for performance in sport.
  2. Most people conflate physical inactivity and nutrition as joint causes of obesity – another link between BJSM’s focus and food.
  3. The traditional ‘nutrition channels’ such as many academic journals in the field, receive substantial funding from major food corporations. And many of the Editorial board members also receive such funding. As BJSM does not receive funding from food corporations, we are ideally placed to share content in the domain.

WE encourage readers to make up their own minds. Enjoy this blog – dare we say it – ‘Food for thought’.

Originally posted on:

ZoeHead1Three! journal articles were published on whole grains in the past couple of weeks; not sure how that happened. Zong et al had this article published in Circulation: “Whole Grain Intake and Mortality From All Causes, Cardiovascular Disease, and Cancer. A Meta-Analysis of Prospective Cohort Studies.” Aune et al had this article published in the BMJ: “Whole grain consumption and risk of cardiovascular disease, cancer, and all cause and cause specific mortality: systematic review and dose-response meta-analysis of prospective studies.” Chen et al had this one published in the AJCN “Whole-grain intake and total, cardiovascular, and cancer mortality: a systematic review and meta-analysis of prospective studies.”

The US Circulation/Harvard team study was the one that dominated the media headlines, not only in the US, but also in the UK, where we were misinformed: “Three slices of wholemeal bread a day slash risk of dying from heart disease by 25%”.

All three studies were meta-analyses of prospective cohort studies. Just to make sense of this – a meta-analysis is generally seen as the highest level of evidence possible. It is a statistical technique to pool together many similar studies, working on the principle that looking at several studies together is more powerful than looking at just one. Prospective cohort studies are also called population studies, or epidemiological studies. These types of studies follow populations over a period of time. At the start of the study they record as many things as possible about the participants’ lifestyle (smoking/alcohol/diet/exercise etc) and they record as many things as possible about the participants’ characteristics (age/gender/education etc) and then they see what happens to the people over the following years. The goal with prospective cohort studies is simply to spot patterns (associations) – do people who drink alcohol get liver disease? Do people who do yoga get fewer diagnoses of stress?

The standard issues

Every time a study hits the headline – e.g. “wearing red socks will reduce your risk of dying from boredom by 25%” – there are two standard issues: association is not causation and relative risk is not absolute risk…

1) Association is not causation.

Observational studies can only establish associations. They cannot say that A causes B. They can only say that A and B are associated. For example, observational studies are good ways of establishing that smoking and getting lung cancer are associated. The next question to ask is – does this have a plausible mechanism? The answer is yes – we have evidence of the ways in which substances in cigarettes damage lungs. We could then test the hypothesis “Smoking causes lung cancer” by conducting a randomised controlled trial where the intervention is smoking vs. not smoking and nothing else changes.

The two studies from last week have shown an association between consuming whole grains and mortality and that’s it. Is there a plausible mechanism? The BMJ article tries to suggest a few (are people who eat whole grains slimmer? Are whole grains anti-inflammatory? Read Dr William Davis’s Wheat Belly book and you’ll conclude the opposite.) There is nothing intrinsically healthy about whole grains, so there is no obvious plausible mechanism. I will suggest below an explanation for the observed association – the marker vs. maker argument.

2) Relative risk is not absolute risk.

I don’t blame the media for this one – I blame the press releases from the journals. These should know better than to put “25% reduced risk” in a press release – knowing that this is misleading relative risk hysteria and not scientific absolute risk information.

European heart data tell us that 33 in every 100,000 men died from coronary heart disease in 2009 and 8 in every 100,000 women died from CHD in 2009. IF eating whole grains were causal and IF eating whole grains could reduce this by 25%, then – taking the women – approximately 7 in 100,000 women in the top whole grain consumption category would be likely to die from CHD and 9 in 100,000 women in the never/hardly ever eat whole grains category would be likely to die from CHD (the difference between 7.1 and 8.9 being just over 25%, while maintaining 8 as the average/mean).

7 vs. 9 in 100,000. Hardly hold the front page now is it?!

The other key points

1) Dietary advice to eat whole grains is not evidence based.

For something to be evidence based, it needs to be based in evidence, If something is based in evidence, the evidence comes first. Advice to consume whole grains dates back to the 1980 Dietary Guidelines for Americans (if not earlier). If you can see the full BMJ article you will notice that only one study that appears in all the meta-analysis results even comes from the last century. This one study, Liu et al, dates back to 1999. All other studies used as evidence are from the year 2000 onwards (a high proportion are from the past couple of years).

Dietary Guidelines have been under serious attack from real food proponents for the past few years. I can understand wanting to try to find retrospective evidence for guidelines in this climate, but it will never make the guidelines evidence based. The evidence didn’t come first and it never will.

2) The comparator group is Jekyll & Hyde.

These studies claim to have found an association between whole grain consumption and reduced mortality (i.e. living longer). The groups that they compared were those in the highest intake of whole grain consumption (more than 3oz per day) vs. those in the lowest intake group. People in the lowest intake group were those who (self) reported “rarely or never” eating whole grains.

The 2010 Dietary Guidelines for Americans tell us: “Less than 5 percent of Americans consume the minimum recommended amount of whole grains, which for many is about 3 ounce-equivalents per day. On average, Americans eat less than 1 ounce-equivalent of whole grains per day.” (p.36)[1]

Hence – both studies have used a very small section of the population as the comparator group (<5%). There are two polarised groups of people in the “never/rare consumers of whole grains”: i) people who avoid all grains and ii) people who eat refined grains instead of whole grains. I would expect whole grain eaters to be healthier than refined grain eaters. The comparison that has not been done is the whole grain eaters vs. the no grains-at-all eaters (the latter, virtually guaranteed, also avoid sugar).

3) Whole grain consumption is a marker, not maker, of a healthy lifestyle.

I would expect people who consume whole grains regularly (the <5%) to: not smoke; not drink; be affluent; do yoga; be slim; shop at Whole Foods/Waitrose; eat at restaurants, not takeaways; have children called Olivia and Tarquin and so on. The whole grain consumption is a marker of good health, not the maker of good health.

The BMJ study noted this as one of the limitations of their research: “People with a high intake of whole grains might have different lifestyles, diets, or socioeconomic status than those with a low intake, thus confounding by other lifestyle factors is a potential source of bias.”

That’s journal speak for “Whole grain consumption is a marker, not maker, of a healthy lifestyle.”

The headlines imply that people just need to up their intake of whole grains and they will “slash their risk of dying from heart disease by 25%!” This could not be further from the truth. It’s not causal, the absolute difference is tiny and it’s a whole lifestyle being depicted in these studies – not a whole grain.

To prove me wrong, the authors of these studies need to give 3oz of whole grains daily to the smoking, drinking, obese, sedentary, aimless, fourth generation unemployed, living-on-benefits, deprived populations in the Welsh valleys and change nothing else. Do you think that will “slash their risk of dying from heart disease by 25%”?!

Me neither.

Regular Consumption of Sports Drinks are a Risk to Children’s Health

29 Jun, 16 | by BJSM


Water or milk is sufficient quote

Regular consumption of sports drinks by children, for social reasons, could be having a detrimental effect on their health concludes the Faculty of Sport and Exercise Medicine (FSEM) UK. A survey by Cardiff University School of Dentistry[i], published in the British Dental Journal, showed a high proportion of 12-14 year olds are regularly consuming, high sugar, sports drinks unnecessarily:

  • 89% of school children are consuming sports drinks with 68% drinking them regularly (1-7 times per week)
  • Half claimed to drink sports drinks for social reasons
  • The high sugar content and low pH of sports drinks increases the risk of obesity, type 2 diabetes, heart disease and the erosion of tooth enamel
  • Most sports drinks are purchased by children in local shops at value prices

The survey looked at 160 children in four schools across South Wales and uncovers that children are attracted to sports drinks because of their sweet taste, low price and availability.  The research highlights the fact that parents and children are not aware that sports drinks are not intended for consumption by children. The FSEM recommends that water and milk is sufficient enough to hydrate children and adults before during and after exercise, there is no evidence of beneficial effects of sports drinks in non-elite athletes or children. However, there is evidence that an increasing consumption of sugar sweetened drinks in the UK increases cardiometabolic risks[ii] and contributes to tooth decay.

Half of the children surveyed claimed to drink them socially and most (80%) purchased sports drinks in local shops, whilst 90% claimed that taste was a factor and only (18%) claiming to drink them because of the perceived performance enhancing effect. The FSEM is calling for tighter regulation around the, price, availability and marketing of sports drinks to children, especially surrounding the school area, to safeguard general and dental health:

Dr Paul D Jackson, President of the FSEM UK comments: “The proportion of children in this study who consume high carbohydrate drinks, which are designed for sport, in a recreational non-sporting context is of concern.

 “Sports drinks are intended for athletes taking part in endurance and intense sporting events, they are also connected with tooth decay in athletes[iii] and should be used following the advice of dental and healthcare teams dedicated to looking after athletes. Water or milk is sufficient enough to hydrate active children, high sugar sports drinks are unnecessary for children and most adults.”    

Russ Ladwa, chair of the British Dental Association’s Health and Science Committee said: “The rise of sports drinks as just another soft drink option among children is a real cause for concern, and both parents and government must take note. They are laden with acids and sugars, and could be behind the decay problems we’re now seeing among top footballers[iv]

“Sports drinks are rarely a healthy choice, and marketing them to the general population, and young people in particular, is grossly irresponsible. Elite athletes might have reason to use them, but for almost everyone else they represent a real risk to both their oral and their general health.”

The FSEM is concerned about an increasing UK trend for the consumption of sports drinks[v] and this schools survey uncovers social reasons, availability and price as having a large influencing factor. Price was one of the top three recorded reasons for purchase and, of particular concern, 26% of children also cited leisure centres as purchase sources.

The survey also addresses the fact that there is particular confusion over the definition of a sports versus an energy drink. However from a dental and wider health perspective, these two drinks have similar detrimental effects due to their high sugar content and low pH.

In supermarkets and shops, sports drinks are sold alongside other sugar sweetened beverages. This is misleading children and parents by indicating that they are meant for use by everyone.

Related BSJM Material:

Tim Noakes, Open Letter: Lobbyists for the sports drink industry: an example of the rise of “contrarianism” in modern scientific debate (BJSM, 2007, OPEN ACCESS).


[i] A survey of sports drinks consumption amongst adolescents. Br Dent J 2016; 220: 639-643, D Broughton BDS (Hons) , RM Fairchild BSc (Hons), PhD, MZ Morgan BSc (Hons), PGCE, MPH, MPhil, FFPH.  Applied Clinical Research and Public Health, College of Biomedical and Life Sciences, Cardiff University, School of Dentistry, Cardiff Metropolitan University, Department of Healthcare and Food.

[ii] Sweetening of the Global Diet, particularly beverages: patterns, trends, and policy responses. The Lancet Diabetes and Endocrinology volume 4, No.2 p174-186, February 2016, Prof Barry M Popkin, PhD, Prof Corinna Hawkes, PhD.

[iii] Faculty of Sport and Exercise Medicine UK, Position Statement, Oral Health in Sport, October 2014, Professor Ian Needleman

[iv] UCL Eastman Centre for Oral Health and Performance Better Oral Health for Footballers Needed, statement published 3 November 2015. Poor oral health including active caries in 187 UK professional male football players: clinical dental examination performed by dentists, Br J Sports Med 2016;50:41-44 doi:10.1136/bjsports-2015-094953, Professor Ian Needleman et al.

[v]  Sales of beverages 2009-2014 in selected countries, data from Euromonitor Passport International, obtained from nutrition fact panels and websites of sugar-sweetened beverage companies kcal = kilocalories, source The Lancet Diabetes & Endocrinology, 2016 4, 174-186DOI: (10.1016/S2213-8587(15)00419-2)


It’s National Obesity Awareness Week and now more than ever we need action.

14 Jan, 16 | by BJSM

By Stephen Morrison @HowManyMiles_

Now more than ever, we need action to prevent the growing trend in obesity and inactivity. Consider this as we encourage you and your peers to sign up for the UK’s National Obesity Forum’s JanUary campaign.

obesitySolutions put forward over ten years ago, are still being called for in new reports. How many reports have to be submitted and how many groups of experts have to gather to discuss obesity and inactivity before recommendations become policy?

“One third of children leaving primary school are overweight or obese, and the most deprived children are twice as likely to be obese than the least deprived. This has serious consequences for both their current and future health and wellbeing and we cannot continue to fail these children. There are many causes and no one single or simplistic approach will provide the answer. We therefore urge the Prime Minister to make a positive and lasting difference to children’s health and life chances through bold and wide ranging measures within his childhood obesity strategy.”

Powerful, emotive and encouraging words from Dr Sarah Wollaston, Chair of the Select Health Committee which published its report on child obesity on 30th November; read it HERE (1).

On the same day, the Faculty of Sport and Exercise Medicine (FSEM) announced that in coalition with a “ground-breaking group…of organisations from different but related fields, including medical, nursing, charity, and public health” it launched a new Obesity Stakeholder Group and produced a joint position to combat the epidemic of obesity.

As a Lay Adviser, to FSEM with special interest in obesity issues, and as a Jamie Oliver Food Revolution Ambassador, it is exciting to see this alliance of agencies work together. The joint position contains ten urgent interventions to hopefully influence the Childhood Obesity Strategy – expected to be published this month – and impact positively on our obesogenic environment. Read the position in detail HERE (2).

I say hopefully, because while the structure of the group is groundbreaking, the ideas are not. Obesity is not a new problem and these two reports are not the first attempts to influence UK Government policy on obesity issues.

Almost all of the recommended interventions called for in these reports were also considered to be urgently required twelve years ago, in a House of Commons Health Committee Obesity Report, which you can read HERE (3)

For instance, the first recommended intervention from the Obesity Stakeholder Group demands that:

“The Government should introduce a ban on advertisements before the 9pm watershed for food and drink products that are high in saturated fat, salt and sugar. Alongside this, regulation governing on-demand services and online advertisements should be tightened to align with broadcast regulations,”

Back in 2003, it was already accepted that advertising for less healthy foods was an issue:

“The Hastings Review offered stark evidence of the extent to which advertisers of less healthy foods were saturating broadcasting slots targeting children, who are often watching without any adult present. While we would not want to go so far as to call for an outright ban of all advertising of unhealthy food, given the clear evidence we have uncovered of the cynical exploitation of pester power we would very much welcome it if the industry as a whole acted in advance of any possible statutory control, and voluntarily withdrew such advertising”

The next intervention highlights the need to combat the pricing and promotion strategies of food retailers:

“Retailers should be set targets to improve in-store architecture to reduce the display of unhealthy foods in areas such as checkouts and end of aisle displays and increase price promotions of healthier alternative products.

In 2003, it was again recognised that the pricing and promotion of unhealthy food contributed to our obesity epidemic:

“As part of their healthy pricing strategies, supermarkets must commit themselves to phasing out price promotions that favour unhealthy foods, and also stop all forms of product placement which give undue emphasis to unhealthy foods, in particular the placement of confectionery and snacks at supermarket checkouts.”

The alliance also demands that:

“The Government should develop an independent set of incremental reformulation targets for industry, backed by regulation and which are measured and time bound. These targets should address salt, sugar and saturated fat levels. Compliance with these targets should be monitored and non-compliance should be backed by meaningful sanctions.”

This echoes the message in 2003:

“We recommend that, rather than targeting sugar and fat separately, the Government should focus on reducing the overall energy density of foods, and should work with the Food Standards Agency to develop stringent targets for reformulation of foods to reduce energy density within a short time frame. While we expect that reformulation could be achieved through voluntary arrangements with industry, and while we believe that the introduction of legislation in respect of labelling will encourage industry to make the entire product range healthier, the Government must be prepared, in the last resort, to underpin this with tougher measures in the near future if voluntary measures fail.”

In 2013, we were “appalled to learn of the desperate inadequacy of treatment and support services for obese children.” 

Fast forward to 2015 and we are still concerned about the provision of weight management services:

“The Government should commit to sustained investment to extend and increase the provision and quality of weight management services for families across the UK.”

I could cite more examples of the present repeating the past. And whilst both reports repeat very valid and necessary changes, there are questions about the lack of action at a policy level that should and need to be answered.

Why, twelve years later, are we still having to ask for these same interventions? How can we hope that today’s experts will be able to secure much needed policy changes.

How do we ensure that, this time, these interventions are implemented?

It is evident that we cannot rely solely on voluntary action by food manufacturers and retailers and that statutory regulation is now unfortunately necessary. The Responsibility Deal has had little effect and has confirmed that businesses are responsible only to their share-holders. Only through direct interventions, from Government or consumers, will they alter their practices.

A recent BMJ paper by Professor Theresa M Marteau highlighted the impact of product and portion sizes on consumer spending and consumption. It included the fact that ‘most national and international policies to prevent obesity highlight a need to reduce portion sizes’ (4). From this, and many other medical based papers, it is difficult to foresee a seismic shift in consumer behaviour without the Government initiating action. However, is there a climate for change within this Government and will they listen and act, or will the pressure placed upon them by other influencing groups prevail?

How many reports have to be submitted and how many groups of experts have to gather to discuss obesity and inactivity before their recommendations become policy?

The costs of obesity and inactivity are too high for these recommendations to be ignored again.

The formation of the Obesity Stakeholder Group is a significant step forward in the fight against obesity and it is to be commended for its bold report, but now, more than ever, we need action, not just words.

Join the NOAW JanUary pledge #dosomethinggoodforU and help turn obesity around


  1. House of Commons Health Committee, Childhood Obesity Brave and Bold Action. First report of session
  2. Obesity Stakeholder Group: Joint Position on Childhood Obesity published by the Royal College of Physicians London November 2015
  3. House of Commons Health Committee, Obesity, Third Report of Session 2003-04 10 May 2004
  4. Professor Theresa M Marteau (December 2015) Downsizing: policy options to reduce portion sizes to help tackle obesity, BMJ 2015;351:h5863


Stephen Morrison is Lay Adviser to the FSEM UK and works for the Department for Work and Pensions. He is an everyday Physical Activity Champion for HASSRA Scotland, a Fitness Day UK Ambassador, and Jamie Oliver Food Revolution Ambassador. Having turned his life and health around with exercise, Stephen’s agenda is to raise awareness of health inequalities and push for a more holistic approach to inactivity within community wide programmes. Stephen also champions the management of obesity with physical activity, the issues surrounding this in the public domain and a call for “a different approach”. Stephen is also a columnist for Man v Fat and charts his journey as a try athlete at

A Festive Virtual Conference – Nutrition

22 Dec, 15 | by BJSM

A monthly round-up of podcasts and articles 

By Steffan Griffin (@lifestylemedic)

seasons-eatings-baconIn the final virtual conference of 2015, the topic is one that is probably most relevant at this time of year – nutrition! Whilst no one should feel guilty about using the time to rest and relax with friends and family, the majority of the population will at some stage want to shed some of the Christmas pounds, and may ask you for advice…

To make it easier for you, we thought we’d collect the most popular nutritional podcasts & papers on the BJSM site – we hope you find them useful (if not interestingly controversial!). Don’t forget to check out our last virtual conference on running, which may come in handy when advising people with well-meaning new-year resolutions!

High-fat for health

A great chat between two legends – Tim Noakes and Peter Brukner. Noakes talks about his views on carbohydrates, and how his experience of a very low carb diet has changed the way he views the decades old advice of low-fat intake – particularly when it comes to treatment of patients with type-2 diabetes and cardiovascular disease. They discuss this diet in the specific setting of sport – long distance and football codes #LCHF

You can’t outrun a bad diet

This is not only one of the BJSM’s most popular podcasts (and editorial), it made headlines around the world and started an international conversation on whether the science supports the notion of energy balance. Karim Khan puts Aseem Malhotra under the spotlight here, and it makes for fantastic listening! You can also listen to Aseem talk on the role of diet in cardiovascular disease, in yet another hard-hitting podcast

The science behind low carb diets for athletes: A rational approach

Is a high-carb diet a requirement for optimal endurance performance? What if that failed to take into account the physiological changes that occur with adaptation to low carbohydrate diets? Stephen Phinney delves into 30 years of research around low-carb ketogenic diets, covering potential benefits in sporting contexts, common criticisms, and future research in the field

The impact of diet on obesity and type 2 diabetes mellitus

We know the guidelines and what the science shows, but does it work in practice? Jason Fung explains the evidence behind the impact of diet on obesity and Type 2 Diabetes Mellitus (T2DM). We also hear how the calories in/calories out model that has previously been described is incorrect, and how T2DM should not be considered a chronic progressive diseases, due to its preventability and reversibility. A thought-provoking concept!

Fit vs Fat….

For an overview of where diet fits into the overall notion of ‘health’, we spoke to Steven Blair, whose research was instrumental in helping physical inactivity gain recognition as a global public health issue. He discusses the wealth of evidence he’s built up on the benefits of exercise, why physical inactivity is a bigger problem than obesity, and how much and of what we should all be doing. A must-listen!


So there we go! We hope you find these resources, which feature some of the most prominent names in the field extremely useful. Please do let the BJSM know your thoughts/questions on twitter, Facebook and in the Google+ SEM community, we are always open to suggestions for new topics! That just leaves us to wish you a lovely festive period and best wishes for 2016, see you in the New Year!

BJSM Podcasts – a year in review

9 Dec, 15 | by BJSM


Fridays are good days. We hope BJSM podcasts add to that feeling.

2015 marked an exciting year for sports physio / sports medicine podcasts. We loved listening to our colleagues’ podcasts – Jack Chew Physio Matters, Adam Meakins (@AdamMeakins), James MacDonald, the MACP, the Naked Physio and Dr Andy Frankyn-Miller. @BJSM_BMJ will feature on Karen Litzy’s New York-based physiotherapy podcast in 2016.

We tried to continually improve our podcasts for our listeners. Feel free to provide feedback. One BJSM goal was more consistent production quality and we feel we made progress over 2014. Thanks a lot to the very patient & dedicated James Walsh, sound engineer and @SportsOsteopath.  The field has progressed very well from the inception of regular sports physio / sportsmedicine podcasts in 2009.

Big, big thanks to our guests – they ARE the podcasts! These guests are now drawing 10,000 listens per week to the > 200 podcasts on the BJSM channel alone!! We love reading tweets about your favourite episodes, and any pearls you learned while riding the tube or bus to work, so keep them coming! (Is cycling and listening to BJSM podcasts safe?). Big shout out to social media specialist Ania Tarazi for creating the BJSM app on top of everything else.

We welcome your suggestions for 2016: email or tweet @BJSM_BMJ

(you can also check out the mid-year podcast review in this BJSM print article:

Below we highlight the 3 most popular podcasts in the last 2 months (Yep, they launched on Fridays). Stay tuned for part two of this series where we profile the most popular podcasts of ALL TIME.

#1. Gold Medal Professor Gwen Jull – Part 1 – Assessment and Management of Neck Pain. First of Two Conversations

Do you treat patients with neck pain? Do you have neck pain? Stop reading and start listening to the podcast. Professor Gwen Jull is one of the most lauded health professionals in the world right now and she shares pearls every minute of this podcast.

0:00m – How do you approach the patient aged in the prime of life who complains of neck pain and bad cervical posture?

2:00m – “Big development in physiotherapy is the assessment /examination which then forms the basis of our treatment” – movement and also how the movement is performed. Facet joint tests, muscle coordination.

3:10m – Detailed specific assessment of posture in the patient with neck pain. Have the patient adopt the work positions. Aim to correct the posture to see if pain changes.

5:10m – How to distinguish the superficial and deep neck extensors

8:30m – 3 trajectories in whiplash patients; folks who get better fairly rapidly (50%), those who suffer persistent mild pain (> 2years, 30%), and ‘the major worry’ of those who have persistent moderate to high levels of pain for many months and sometimes going on for years. What predicts these trajectories? “The last group is a real stumbling block for all professions”.

11:00m – Predictors of the poor outcomes.

Follow THIS LINK for the complete timeline.

#2. Silver Medal Keeping runners running: the secrets of running assessment – advice and exercise progressions

Mo Farah has great running technique. You see it, you know it. But what are the elements of Mo Farah’s running style? Can we assess running patients and guide them to improve their technique? Might gait education prove more effective than medication to treat symptoms? Andy Cornelius has the answers. He’s a Graduate Sport Rehabilitator and head running coach who works in private clinics, premiership football and with high profile clubs and athletes. Posing the questions is Stephen Aspinall, Chairman of the British Association of Sports Rehabilitators and Trainers (BASRaT – and Lecturer in Sport Rehabilitation at the University of Salford, England.

1:20m – What are the key elements of running assessment?

2:45m – What you can learn by watching the runner from behind (frontal plane) and the side (sagittal plane) on the track and on the treadmill.

4:08m – The runner with injuries related to overstriding. What is overstriding? What can the clinician advise?

6:00m – Assessing cadence and helping the athlete to make a change of between 5-10% in cadence.

Follow THIS LINK for a complete timeline

#3. Bronze Medal Prof Stephen Phinney on the science behind low carb diets for athletes: A rational approach

Consider the classic understanding that high carbohydrate intakes are necessary for optimal endurance performance. What if that failed to take into account the physiological changes that occur with adaptation to low carbohydrate diets? In this podcast, @JohannWindt interviews physician-researcher Dr. Stephen Phinney about his last 30 years of research into low-carb ketogenic diets. Highlights include the previously undocumented levels of during exercise fat oxidation seen in endurance athletes adapted to a low carbohydrate diet. He also touches on ketogenic diets’ potential benefits in other sporting contexts, addresses common criticisms, and looks ahead to future research questions in the field.

Further reading and papers discussed in the podcast are included below.

Vermont and MIT Study Dr. Phinney’s original two studies on low carbohydrate performance. Original two low carb performance studies.…5-1/abstract

Phinney SD et al. The human metabolic response to chronic ketosis without caloric restriction: physical and biochemical adaptation. Metabolism 1983;32:757-68.…5-1/abstract

Phinney SD et al. capacity for moderate exercise in obese subjects after adaptation to a hypocaloric, ketogenic diet. J Clin Invest 1980;66:1152-61.

The gymnast study mentioned in the podcast: Paoli et al. Ketogenic diet does not affect strength performance in elite artistic gymnasts.
J Int Soc Sports Nutr 2012; 9: 34.

Significant decrease in inflammation shown in low carb diets by Forsythe, Phinney, et al.Comparison of low fat and low carbohydrate diets on circulating fatty acid composition and markers of inflammation. Lipids 2008;43:65-77.…7?no-access=true

Prof Phinney’s recent BJSM Editorial: Noakes T, Volek JS, Phinney SD. Low-carbohydrate diet for athletes: what evidence? Br J Sports Med 2014…014-093824.extract

Prof Phinney and Volek’s website– Art and Science of Low Carbohydrate Living/Performance

In the August 2015 issue of BJSM you’ll find a series of paper on weight loss and physical activity:

Dr Aseem Malhotra’s paper: It’s time to bust the myth of physical inactivity and obesity: you can’t outrun a bad diet (if you want to be thin) (OPEN ACCESS) Coauthors are Professor Phinney and Professor Timothy Noakes (@ProfTimNoakes).

Professor Stephen Blair’s rebuttal: Physical inactivity and obesity is not a myth: Dr Steven Blair comments on Dr Aseem Malhotra’s editorial

Professor Kamal Mahtani’s editorial: Physical activity and obesity editorial: is exercise pointless or was it a pointless exercise?

Two relevant BJSM podcasts include:

1) Professor Tim Noakes interviewed by Professor Peter Brukner
2) Dr Aseem Malhotra discussing the debate around his editorial above

BJSM editors appreciate that nutrition is a controversial issue (not sure why, but that’s OK) so please note the Prof Phinney’s competing interests are listed in BJSM revels in debate and publishes quality material. Hence, you can see divergent views represented above and we have commissioned an editorial from respected scientists who feel that protein, or carbohydrate, deserves greater prominence. Your submissions are welcome via the BJSM’s various channels – ‘print’, rapid response, blog, Google plus community, twitter, Facebook. Or email

Passionate about proactive healthcare? Look no further…#MET2015

14 Oct, 15 | by BJSM

Move Eat Treat is a movement to equip all healthcare practitioners with the skills to positively influence their patients’ lifestyle choices, fostering a healthy and happy Great Britain.

move eat treat Updated_Logo_Pill_OnlyAs follow-up from our groundbreaking inaugural summit in 2013, we invite you to join us at the Institute of Sport Exercise and Health (ISEH) in London on Wednesday 18th November. We will critically discuss the recent progress and future of integrating lifestyle teaching into medical education. Our overarching aim is to encourage a more proactive healthcare system.

Talks will address important lifestyle issues such as nutrition, physical activity and positive psychology, and feature keynote talks from:

  • Dr Aseem Malhotra,
  • Dr Richard Weiler,
  • Dr Mike Loosemore
  • and Dr Tim Anstiss; amongst others.

There will be multiple panel discussions throughout the day to encourage dialogue and collaboration. Our last summit was an enthusiastic mix of those working in the healthcare profession, politicians, industry leaders as well as members of the media – this diverse audience made for rich conversation. We hope to replicate and build off of this diversity, and as thus, ask for your help to spread news of the summit!

And of course if proactive healthcare is something you’re passionate about, we would love for you to join us.

If you are unable to attend on the day, still get involved in the discussion on social media by using the hashtag #MET2015.

For tickets, visit this link:

For more information about Move Eat Treat, you can visit the website or follow us on twitter @moveeattreat


It’s not just BJSM talking about healthy nutrition – real food…

21 May, 15 | by BJSM

Whether listening to the radio or reading the newspaper in the last few weeks, it’s likely that you noticed the BJSM gaining a fair amount of media coverage. The attention has centred on the issue of diet & weight loss (not surprisingly, fuelling a more spirited debate than the average hamstring injury article!), specifically, an editorial by Dr Aseem Malhotra, which suggests that physical activity without consideration of diet, is insufficient in the fight against obesity.

obesity 1

Some media outlets portrayed the article as driving a nail into the coffin of physical activity as a preventative health modality, failing to mention that the editorial argued strongly that a minimum of 30 minutes of physical activity a day provides a great return-on-investment for all-round health. @DrAseemMalhotra simply questioned the evidence-base regarding the effectiveness of physical activity alone in reducing obesity, an independent health issue in its own right. He also provides a call-to-action to “bust the myth of physical inactivity and obesity,” namely the misconception that if you exercise you can eat whatever you want with no health concern.

That article was preceded by a perspective from the University of South Carolina and ACSM’s esteemed Professor Steven Blair, a BJSM Senior Associate Editor. He and two colleagues point out the imbalance in energy balance research, and call for further investigation into the concept of ‘energy flux’ in causing obesity; the Global Energy Balance Network is already undertaking some of this work.

Professor Blair directy rebutted to the Malhotra editorial as a blog on the Global Energy Balance Network website and shared this via his wide reach on Twitter (@StevenNBlair). That blog is about to be accepted as an editorial in BJSM and it, and another relevant editorial will be in BJSM issue #15 (July) – curated by the South African Sports Medicine Association.

So what actually works?

Whilst obesity levels expand and expand, discussion around the optimal diet to reverse this trend include the practice of reducing carbohydrates and increasing fat intake. The optimal extent of these changes are also the topic of intense debate. BJSM published an editorial by Professors Noakes and Phinney on the argument for a low carbohydrate, high fat diet #LCHF. Dr Peter Brukner, (@PeterBrukner) a self-avowed #LCHF convert, interviewed Professor Noakes on this BJSM podcast. Importantly, BJSM has commissioned a counterpoint from leaders in sports nutrition and performance.

If you are open to challenging ideas, here are links to the #LCHF summit conference highlights1,2,3, whilst you can also enjoy Dr Malhotra’s provocative podcast on #DontFearTheFat and the more recent one clarifying his editorial.

Whether you’re a #LCHF advocate or have never heard of it before, one of the most impressive educational resources that discusses the issue is a TEDx video by Dr Sarah Hallberg – Medical Director of the Medically Supervised Weight Loss Program at IU Health Arnett. She provides insight into the cultural interests that led to the normalization of high carb low fat diets, and proliferated the diabetes and obesity epidemic. She also explains practical, diet based, strategies to combat these diseases. So if you want to learn more about why you shouldn’t fear the fat, sit back (or stand…) and enjoy.

Whilst cutting carbohydrates has historically been associated with celebrity diets, the mounting evidence is hard to ignore, as is this diet’s establishment as a sustainable and effective way to fight obesity. If you need further convincing (or haven’t the time to watch the clip), why not listen to Dr Jason Fung discuss the issues of insulin and diet in relation to type 2 diabetes and obesity. Enjoy these resources and join the conversation on our social media platforms (Twitter, Facebook & Google+).

Blog References

PART 2: To #LCHF or not to #LCHF; That’s the dietary question!

15 Mar, 15 | by BJSM

By @JohannWindt, @Liam_West & Ania Tarazi

This is part 2 of the’ To #LCHF or not to #LCHF’ Summit summary. Read part 1 HERE

In this post, we focus on the low carb high fat diet (LCHF) and performance, and finish off with the pros and cons of the #LCHF2015 summit. We hope you enjoyed BJSM Editorial team’s coverage from the summit in Cape Town! Follow the #TeamBJSM on @BJSMPlus for future SEM event coverage!


#LCHF and #EndurancePerformanceruntrackcrop

#RunOnFat – More than the name of the exclusive screening of the new documentary featuring Dr. Stephen Phinney and Prof. Tim Noakes, this describes how adaptation to a #LCHF diet may impact endurance performance. Professor Tim Noakes, Dr. James Smith, and Dr. Stephen Phinney all demonstrated that fat oxidation rates are significantly higher in athletes adapted to a #LCHF diet than any other athletes. They identify that an adaptation period is necessary for performance to return to performance levels with higher carbohydrate content. This may explain the significant portion of the research supporting high carbohydrate diets, as the athletes with lower carbohydrate content in their diets were not on the diet long enough to adapt. The increased fat oxidation level as a result of a high fat diet corresponds to slower rates of glycogen depletion, thereby offering a theoretical benefit to improved endurance performance, and less dependence on exogenous carbohydrate intake during prolonged activity. At this point, data is mixed between beneficial effects and no documented effects on endurance performance on LCHF diets. More research is necessary to determine whether athletes adapted to the diet are capable of maintaining/improving sprint performance and peak power outputs, since sprint performance appears to decrease under carbohydrate restricted conditions.

#LCHF and #Strength/Power Sports

Most of the discussion at the conference focused on #LCHF diets and endurance performance, with little addressing strength/power sporting contexts. With the exception of a study in gymnasts, showing stable performance in the presence of fat and weight loss, no literature has examined this area in depth. In addition to their potential use in helping these athletes lose fat, further research is needed as to whether this diet contributes to  significant performance benefits.

As identified by Noakes, Phinney and Volek in their recent editorial, many research questions remain in this field. Namely, the effects of #LCHF adaptation on recovery ability and total training volume, their immune function and overtraining risk, sports requiring high levels of hand-eye coordination and mental acuity (i.e. Golf & Cricket), and their efficacy in allowing for weight control. While #LCHF adaptation can significantly increase rates of fat oxidation, it remains to be seen if this translates to improved performance in endurance events.


#LCHF2015 Summit summary and final considerations 


  • The conference included a global speaker line-up and addressed #LCHF diets from a variety of perspectives, including weight, CVD risk, glycemic control, mental health, anthropology, history, psychology and more.
  • The speakers consistently voiced that low carbohydrate diets are not the only way to success/health, but that they should be considered as an effective, healthy option.
  • The conference itself ran very smoothly and was very well-organized seeing over 400+ each day register.


  • Certain portions of the conference were heavier in anecdotes/case studies than scientific data. On occasion, unsubstantiated claims without supporting data were made. During the first 3-day medical part of the conference, it is vital to remain consistently evidence-based.
  • #LCHF can cause some confusion. The demonization of “carbohydrates” can lend to the misunderstanding that all carbohydrate sources, from fruits and vegetables to refined, sugary breakfast cereals and pastries are the same. The recommendations to consume unprocessed, nutrient dense foods must be emphasized, after which point the restriction of certain carbohydrate sources may be warranted.
  • Many speakers failed to elaborate beyond the carbs à insulin à fat model, which fails to account for other factors associated with weight gain. Acknowledgement of other factors, and more thorough explanations are warranted.

Far from a simple fad, #LCHF diets have a growing body of evidence in their favour. #LCHF diets are extremely effective for weight loss, glycemic control, and improve a large number of CVD risk factors. Adaptation to this diet also significantly increases rates of fat oxidation during exercise. It is true that no long-term trials have demonstrated their efficacy beyond two years. However, the significantly positive effects from RCT evidence should validate their use, especially since the long term effects of the low-fat diet have not proven to be beneficial beyond a control diet after 8 years. To demonize them as a ‘fad diet’ fails to honestly examine the evidence, which indicates both their efficacy and safety. #LCHF diets may not the only way to eat, but they should be considered as a viable option.

With that said, many questions remain. Long-term trials are still called for to examine the effects of long-term adherence to a #LCHF dietary plan. What factors help to explain individual variability in response to #LCHF diets? What are the long-term effects of nutritional ketosis? In terms of performance, further investigation into different performance parameters, sporting contexts, recovery rates, and weight control remains necessary.

Overarching the whole #LCHF summit was an insistence on nutrient dense #RealFood, thereby #AvoidProcessedFood stripped of fiber and containing additional sugar. Thus, we conclude by insisting a focus on eating #RealFood, and if desired to try a #LCHF approach to nutrition.


Johann Windt BHK CSCS (@JohannWindt) is a graduate student at the University of British Columbia in the Department of Experimental Medicine. His research currently focuses on physical activity prescription and lifestyle counseling in family medicine settings. A certified strength and conditioning coach, Johann is passionate about improving health, body composition, and performance through evidence-based application of nutrition and physical activity. 

Dr. Liam West BSc (Hons) MBBCh PGCert SEM (@Liam_West) is a Cardiff Medical School graduate and now a junior doctor at the John Radcliffe Hospital, Oxford. He is an Associate Editor for BJSM and also coordinates the “Undergraduate Perspective on Sports & Exercise Medicine” Blog Series.

Ania Tarazi BSc (Hons)  (@AniaTarazi) coordinates the Aspetar Sports Medicine Journal in Doha, Qatar. Ania graduated from Royal Holloway University of London with an International Business degree in 2013. Her interests lie in social media engagement to promote physical activity and healthy eating in children.

PART 1: To #LCHF or not to #LCHF – that’s the dietary question!  

12 Mar, 15 | by BJSM

By @JohannWindt, @Liam_West@AniaTarazi

Cape Town International Convention Centre

Cape Town International Convention Centre

Attendees of the 2015 Old Mutual Health Convention were fattened with four full days of low-carb, high fat (#LCHF) information #PunIntended. For brief summaries, see daily blogs of Day 1, Day 2, and Day 3. Combining our notes, conference speaker interviews, and your questions, #TeamBJSM hope this blog captures and summarizes the main scientific research presented at the summit. We have hyperlinked relevant papers in green for you to make up your own mind about the diet – #NoBias. There will be two parts: “#LCHF and #Health” and the second, “#LCHF and Performance”. Here, in part 1, we look at LCHF in respect to weight loss, cardiovascular risk and glycemic control and answered the common misconceptions about the diet.


#LCHF for weight loss:

Physiological Basis – Hormonal Model Adopted – The central basis of the low-carbohydrate diet is adoption of the hormonal model of obesity, as opposed to a strictly energy balance model. They suggest that a purely calorie-based model (energy in vs. energy out) is insufficient, and the interplay of dietary intake, hormonal and physiological responses is key to understanding weight control. Most speakers highlighted the role of dietary carbohydrates in raising insulin levels, thereby encouraging the body to store fat (de novo lipogenesis), and block fat breakdown (lipolysis). Support for this model includes differential weight loss in isocaloric conditions, and different weight loss in low-carbohydrate vs. low fat diets, dependent upon insulin resistance. Bonus reading here & here.

Trial Evidence – Low Carbohydrate Diets vs. Other Diets – A number of speakers presented evidence that low carb diets have outperformed low-fat diets (related reading; one, two, three)  and low glycemic index diets  in randomized trials of weight loss. This observation has been picked up in a number of systematic reviews regarding the efficacy of low carbohydrate diets – links to read here; one, two & three. Notably, it was identified the low-fat diets were deliberately energy controlled (with prescribed kcal to induce weight loss), while the low-carbohydrate diets were unrestricted in energy intake, yet still outperformed low-fat counterparts.

Caveats and Misconceptions – First a calorie is a calorie. It’s a unit of energy, it measures the potential energy food can release. Therefore #CaloriesStillCount. But, it must be emphasised, two equal calories can produce different biological effects to body fat or body weight, i.e. a calorie of protein vs a calorie of refined carb. Second, carb intake leading to fat storage is an oversimplification. Dr. Jason Fung aptly presented that the “carbs leading to insulin leading to fat” hormonal model is a part of the puzzle, but fails to take into account all aspects. With the cycle of increased serum insulin, leading to insulin resistance, causing higher serum insulin, etc. at the center of the model, he identified three central players that all link to Insulin:

  • Carbohydrates – As often identified in the hormonal model above, cause increased insulin levels and can if consumed in too high quantities and frequencies, contribute to insulin resistance.
  • Fiber – Helps reduce insulin levels #Protective – see papers here – one & two
  • Fructose – Unique capacity to induce insulin resistance, thereby exacerbating the problems.

Since the refining/processing of foods often strip the fiber from foods, and add additional fructose, they are especially harmful in inducing weight gain. #CheckFoodLabels

Therefore, the consistent take-home messages from the conference in terms of weight control included #RestrictCarbs, #EatRealFood, & #AvoidProcessedFoods.

#LCHF and cardiovascular risk:

Conventional wisdom states that too much fat increases fat and cholesterol in the bloodstream, and contributes to cardiovascular risk – commonly called the diet-heart hypothesis. If true, a LCHF diet is a tremendous risk, and will predispose people to heart attacks and CVD. However, these fears must be reconsidered in light more recent data.

Systematic reviews – click on one, two & three to view – examining the LCHF diet and cardiovascular risk factors, showed significantly:

  • Improved weight, BMI and waist circumference
  • Increased HDL, which serves as protective against heart disease
  • Decreased triglyceride levels
  • Decreased systolic and diastolic blood pressure
  • Decreased fasting plasma glucose
  • Decreased Insulin levels
  • Decreased HbA1c levels

Further evidence also suggests:

  • Reduced levels of saturated fats in the bloodstream
  • Reduced inflammatory biomarkers

The ‘red-flags’ to patients on a LCHF diet is the variable response of LDL levels, and average increase in total cholesterol levels. In terms of total cholesterol increases, this is predominantly or exclusively due to HDL increases, serves as protective to CVD, and is not seen as a major concern. Though the average LDL level is usually unaltered, it must be taken into account with a LCHF diet and CVD. It was pointed out that LDL levels are only one component of CVD risk, the rest of which all improve on LCHF. In addition to this, the particle sub-fractions of LDL change positively in response to LCHF, not negatively – check out two interesting papers here & here. Nonetheless, total cholesterol and LDL responses on a LCHF diet are variable, and more research will have to investigate these parameters.

To wrap up, cardiologist Dr. Aseem Malholtra identified that the best evidence to date for primary prevention of CVD is for the Mediterranean diet from the PREDIMED study; with the supplementation of EVOO and raw nuts and total of 41% fat content. He recently highlighted that saturated fat is not the major issue, and data on LCHF diets and CVD risk factors lend support to their safety from a CVD standpoint.

#LCHF and Glycemic Control:

LCHF diets effectively reduce body weight, insulin levels, fasting glucose levels, reduce insulin resistance, and significantly reduce HbA1c – evidence to back this up? Read 2 papers here & here. Hence, they are extremely effective in improving glycemic control and type 2 diabetes.

Dr. Jason Fung addressed the underlying issue of insulin resistance in T2DM, highlighting the fact that controlling blood sugar levels through intensive glucose lowering in diabetic patients has little benefit on mortality. He stated that a focus on blood sugar levels, as a chronic, progressive disease promotes learned helplessness and fails to take the current evidence into account. He highlights that both bariatric surgery  and fasting/extreme energy restriction have potent effects in reducing insulin resistance and reversing diabetes. Similarly, efforts should be made to control insulin levels and reduce the underlying insulin resistance through dietary strategies. This can best be achieved through restricting refined carbohydrates, increasing fiber intake, and removing fructose from the diet.

Challenging Guidelines

As expected, the national dietary guidelines of were touched on by a number of the speakers, including Gary Taubes and predominantly Zoe Harcombe. Presenting her recent paper, she highlighted that the randomized trial evidence at the time of the national guideline introductions in the US and UK was insufficient to prescribe a low-fat message.

An overarching theme of the conference was that ‘one-size-fits-all’ dietary guidelines that continue to restrict fat and cholesterol intake are not fair to the existing evidence. As discussed, Mediterranean diets with over 40% fat intake have continuously shown positive health outcomes. Furthermore, #LCHF diets reduce weight, cardiovascular risk, and glycemic control. This differs from the guideline recommendations.

Addressing Misconceptions:

Below we have tried to briefly address some #LCHF common misconceptions

“#LCHF treats all food as the same, as long as carbs are controlled”:

  • Consistently, all speakers presented that nutrients should come from #Unprocessed #RealFood, with high nutrient density and minimal processing.
  • All carbohydrates are the not the same, and intake should come from whole, unprocessed foods, green leafy vegetables, cruciferous vegetables, and minimal fruit.
  • Fats are not all the same. Mono and saturated fats are recommended on a #LCHF diet, while polyunsaturated sources should not be consumed in high quantities.

“What about Ketosis?”

  • Nutritional ketosis and diabetic ketoacidosis are entirely separate physiological states #Important
    • Nutritional ketosis has a blood ketone level of 0.5-2.0 mmol/L, with post-exercise ketosis up to about 3.0
      • Starvation ketosis can elevate levels up to 5.0-7.0 mmoL/L.
      • Ketoacidosis occurs with levels of 10 mmol/L or more
    • Ketones can serve as a primary fuel source for the brain during carbohydrate restriction.
    • There is emerging evidence for the benefits of ketogenic diets in various health conditions, including epilepsy, neurogenerative diseases, cancer, polycystic ovary syndrome, to name a few – see the evidence here, here & here.

“Higher saturated fat intakes on low-carb diets would cause higher saturated fats in bloodstream”

“Excess protein intake on a low-carb diet is dangerous”

  • Most low carbohydrate diets are moderate protein diets, with 15-25% of calories coming from protein.

“#LCHF insists that low-carb diets are universally the best diet”

  • Individual responses to low-carb diets vary, meaning #LCHF does not suit all! However, they should be considered as a safe, viable dietary option.
  • Insulin resistance can be reduced with a low-carb diet. Therefore, those with insulin resistance of type 2 diabetes may respond more favourably to a low-carb diet than those who have greater insulin sensitivity.

“Nutrient density is low on a low-carb diets”

  • If a #LCHF diet is followed as recommended at the conference (i.e. #RealFood, #Unprocessed), nutrient density will be attained through intake of a variety of vegetables, meat, and dairy. If attention is paid to eating whole foods from a variety of sources, all the micronutrients that would be attained on a high carb can be attained on a #LCHF diet.

Additional Considerations

Alongside a ‘well-formulated’ ketogenic diet, as described by Drs. Westman and Phinney, some additional sodium and magnesium intake may be recommended to help to prevent muscle cramps in susceptible individuals.

In Part 2 of ‘To#LCHF or not to #LCHF’ we’ll take a look at “LCHF and Performance”. Starting with the view of a LCHF diet on endurance performance and the need for an adaption period. We’ll take a look at the pros and cons of the summit and our take home message from #LCHF2015.


Johann Windt BHK CSCS (@JohannWindt) is a graduate student at the University of British Columbia in the Department of Experimental Medicine. His research currently focuses on physical activity prescription and lifestyle counseling in family medicine settings. A certified strength and conditioning coach, Johann is passionate about improving health, body composition, and performance through evidence-based application of nutrition and physical activity. 

Dr. Liam West BSc (Hons) MBBCh PGCert SEM (@Liam_West) is a Cardiff Medical School graduate and now a junior doctor at the John Radcliffe Hospital, Oxford. He is an Associate Editor for BJSM and also coordinates the “Undergraduate Perspective on Sports & Exercise Medicine” Blog Series.

Ania Tarazi BSc (Hons)  (@AniaTarazi) coordinates the Aspetar Sports Medicine Journal in Doha, Qatar. Ania graduated from Royal Holloway University of London with an International Business degree in 2013. Her interests lie in social media engagement to promote physical activity and healthy eating in children.

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