Imagine being at the 60th anniversary of an organization and hearing from the first head of the organisation. It seems impossible, but I’ve just had that experience – listening to Nevin Scrimshaw, aged 91, describe the challenge and the excitement of the early days of the Institute of Nutrition of Central America and Panama (INCAP). Almost as remarkable, all six of the directors of INCAP are still alive – perhaps a tribute to their knowledge of nutrition.

Scrimshaw was awarded the World Food Medal (the “Nobel prize of nutrition”) in 1991 and went on from INCAP to found the Department of Nutrition and Food Science at the Massachusetts of Technology and the United Nations University as well as starting and directing the World Hunger Programme. But he made clear in his talk that his years at INCAP from 1949 to 1961 were his happiest and most productive – despite having to nail back the roof after it was blown off during a storm.

INCAP, which covers all the countries of Central America and the Dominican Republic, was founded with a three part mission; research, capacity building, and technical assistance. All three are still important. It’s the research that has made INCAP famous internationally, but the technical assistance has saved many lives in the poor countries of Central America.

What I realized listening to Scrimshaw and others was that much of what I learnt on nutrition at medical school was discovered at INCAP. Kwashiorkor was common in Guatemala, the home of INCAP, in the late 40s and 50s, and the INCAP team realized that it struck when children were no longer breast fed. They helped unravel the causes of kwashiorkor and searched for a food source to prevent it. The result was Incaparina, a vegetable protein that was much cheaper than milk and is now given to many of the children in Central America, where malnutrition is still common. There are various versions of Incaparina, and new ones are being developed. It’s commercially available and a major source of income for INCAP.

Goitre was endemic in Central America, but iodizing salt was difficult as it didn’t come in neat containers as in the developed world but rather in a moist dollop. INCAP worked out how to iodise that kind of salt and within a few years goitre had almost disappeared. Guatemala was the first developing country to reduce goitre right across the country. INCAP also led the way with fortifying sugar with vitamin A to counter widespread deficiency of the vitamin. Many foods in Central America are fortified, compensating for inadequate diets and raising none of the philosophical objections that are common in countries like Britain.

INCAP is also famous for its Nutrition Trial Cohort Study that began in 1969 and has produced many useful results described in over 300 publications. The study began as a randomised trial to test the hypothesis that improved preschool nutrition would enhance mental development. Children in two villages received Atole (Incaparina, skimmed milk, and sugar) while children in two control villages received Fresco (a small amount of sugar and flavouring, no protein). Some 2392 children were entered into the trial between 1969 and 1977, and the cohort is still being followed up.

The study has shown the substantial benefits of preschool nutrition and that they persist. Children fed Atole between 0 and 24 months have net wages 46% higher than those fed Fresco. Importantly, the children fed Atole are not more obese and do not have higher cardiometabolic risk factors; indeed, there is some evidence that they may be at lower risk.

These last findings are important because Central America – like most of the developing world – is now experiencing a pandemic of chronic disease. Some 25% of children in schools in Guatemala are overweight – despite the families of the children being mostly poor. I visited a school, where I was photographed with the director in front of the school shop. The photograph shows that I’m about 50 cm taller than the director and that the shop carries a huge advertisement for Coca Cola and sells only sweets and sugary drinks. (I leant at the conference that poor children in the US get 25% of their calories from sugary drinks.)

Yet just days before I stood in that school nine children had died of malnutrition in a hospital in another part of Guatemala. This is the terrible double burden of developing countries, and INCAP is working to reduce both.