Traditional Lp(a) Treatments:

Niacin reduces Lp(a) up to 75%.
Testosterone and estrogen reduce Lp(a) up to 59%.
Aspirin reduces Lp(a) up to 46%.

Unique Lp(a) Treatments:
Omega-3 fatty acids may reduce Lp(a) up to 48%.
Low cardohydrate diets may reduce Lp(a) up to 13%.
The dairy protein casein may modestly reduce Lp(a) while soy protein has shown both increases and decreases.
Several studies have shown alcohol can reduce Lp(a) up to 57%.
DHEA has been shown to decrease Lp(a) up to 18%.
Flaxseed and almonds have been shown to reduce Lp(a) slightly.
One study demonstrated a 12% Lp(a) reduction using Co-Q10.
Several publications report small Lp(a) reductions using L-Carnitine.
N-acetylcysteine is a novel agent that demonstrated Lp(a) reductions of over 70% in one small study.
Fibrates have produced average Lp(a) reductions averaging 17%.
Thyroid hormone supplementation has produced Lp(a) reductions of up to 50%.
Certain Diabetes treatments have have effectively reduced Lp(a) 10-46%.
A preliminary study showed a 23% reduction in Lp(a) using Gingko-biloba.

If I am somehow wrong - please write and explain why.

References:

Akaike M, Azuma H, Kagawa A et al. Effect of Aspirin Treatment on Serum Concentrations of Lipoprotein(a) in Patients with Atherosclerotic Diseases. Clin Chem 2002;48: 14541459.

Barnhart KT, Freeman E, Grisso JA et al. The effect of dehydroepiandrosterone supplementation to symptomatic perimenopausal women on serum endocrine profiles, lipid parameters, and health-related quality of life. J Clin Endocrinol Metab. 1999 Nov;84(11):3896–3902.

Beil FU, Terres W, Orgass M, Greten H. Dietary fish oil lowers lipoprotein(a) in primary hypertriglyceridemia. Atherosclerosis 1991;90:95–97.

Berthold HK, Unverdorben S, Degenhardt R, Dipl-Stat MB, Gouni-Berthold I. Effect of policosanol on lipid levels among patients with hypercholesterolemia or combined hyperlipidemia: a randomized controlled trial. J Amer Med Assn. 2006 May 17;295:2262–2269.

Bostom AG, Hume AL, Eaton CB et al. The effect of high-dose ascorbate supplementation on plasma lipoprotein(a) levels in patients with premature coronary heart disease. Pharmacotherapy 1995 Jul-Aug;15(4):458–464.

Carlson LA, Hamsten A, Asplund A. Pronounced lowering of serum levels of lipoprotein(a) in hyperlipidaemic subjects treated with nicotinic acid. J Intern Med 1989;226(4):271276.

Catena C, Novello M, Dotto L, De Marchi S, Sechi LA. Serum lipoprotein(a) concentrations and alcohol consumption in hypertension: possible relevance for cardiovascular damage.
J Hypertens. 2003 Feb;21(2):281–288.

Cicero AFG, Derosa G, Miconi A et al. Treatment of massive hypertriglyceridemia resistant to PUFA and fibrates: A possible role for the coenzyme Q10? BioFactors 2005;23:7–14.

Clevidence BA, Judd JT, Schaefer EJ et al. Plasma lipoprotein(a) levels in men and women consuming diets enriched in saturated, cis-, or trans-monounsaturated fatty acids. Arterioscler Thromb Vasc Biol 1997 Sept; 17(9):1657–1661.

Danesh J, Collins R, Peto R. Lipoprotein(a) and coronary heart disease: meta-analysis of prospective studies. Circulation 2000;102:1082–1085.

Derosa G, Cicero AFG, D’Angelo A et al. Effects of 1 year of treatment with pioglitazone or rosiglitazone added to glimepiride on lipoprotein (a) and homocysteine concentrations in patients with type 2 diabetes mellitus and metabolic syndrome: a multicenter, randomized, double-blind, controlled clinical trial. Clin Ther 2006 May;28(5):679–688.

Drowatzky KL, Durstine JL, Irwin ML et al. The association between physical activity, cardiorespiratory fitness, and lipoprotein(a) concentrations in a tri-ethnic sample of women: The Cross-Cultural Activity Participation Study. Vasc Med 2001;6(1):15–21.

Dullaart RP, van Doormaal JJ, Hoogenberg K, Sluiter WJ. Triiodothyronine rapidly lowers plasma lipoprotein (a) in hypothyroid subjects. Neth J Med 1995 Apr;46(4):179–184.

Durstine JL, Davis PG, Ferguson MA, Alderson NL, Trost SG. Effects of short-duration and long-duration exercise on lipoprotein(a). Med Sci Sports Exer 2001 Sep;33(9):1511–1516.

Espeland MA, Marcovina SM, Miller V et al. Effect of postmenopausal hormone therapy on lipoprotein(a) concentration. PEPI Investigators. Postmenopausal Estrogen/Progestin Interventions. Circulation 1998 Mar 17;97(10):979–986.

Farnier M, Bonnefous F, Debbas N, Irvine A. Comparative efficacy and safety of micronized fenofibrate and simvastatin in patients with primary type IIa or IIb hyperlipidemia. Arch Intern Med 1994 Feb 28;154(4):441–449.

Fontana P, Mooser V, Bovet P et al. Dose-dependent inverse relationship between alcohol consumption and serum Lp(a) levels in black African males. Arterioscler Thromb Vasc Biol 1999 Apr;19(4):1075–1082.

Foody JM, Milberg JA, Robinson K, Pearce GL, Jacobsen DW, Sprecher DL. Homocysteine and lipoprotein(a) interact to increase CAD risk in young men and women. Arterioscler Thromb Vasc Biol 2000;20:493–499.

Gavish D, Breslow JL. Lipoprotein(a) reduction by N-acetylcysteine. Lancet 1991;337:203–204.

Gurakar A, Hoeg JM, Kostner G, Papadopoulos NM, Brewer HB Jr. Levels of lipoprotein Lp(a) decline with neomycin and niacin treatment. Atherosclerosis 1985;57:293–301.

Harpel PC, Chang VT, Borth W. Homocysteine and other sulfhydryl compounds enhance the binding of lipoprotein(a) to fibrin: a potential biochemical link between thrombosis, atherogenesis, and sulfhydryl compound metabolism. Proc Natl Acad Sci 1992;89:10193–10197.

Hartgens F, Rietjens G, Keizer HA et al. Effects of androgenic-anabolic steroids on apolipoproteins and lipoprotein(a). Br J Sports Med 2004;38:253–259.

Herrmann W, Biermann J, Kostner GM. Comparison of effects of N-3 to N-6 fatty acids on serum level of lipoprotein(a) in patients with coronary artery disease. Am J Cardiol 1995 Sep 1;76(7):459–462.

Hopkins PN, Wu LL, Hunt SC et al. Lipoprotein(a) interactions with lipid and nonlipid risk factors in early familial coronary artery disase. Arterioscl Thromb Vasc Biol 1997;17:2783–1792.

Huang CM, Elin RJ, Ruddel M, Schmitz J, Linnoila M. The effect of alcohol withdrawal on serum concentrations of Lp(a), apolipoproteins A-1 and B, and lipids. Alcohol Clin Exp Res 1992;16:895–898.

Insua A, Massari F, Rodriguez Moncalvo JJ et al. Fenofibrate of gemfibrozil for treatment of types IIa and IIb primary hyperlipoproteinemia: a randomized, double-blind, crossover study. Endocr Pract 2002 Mar-Apr;8(2):96–101.

Jenkins DJ, Kendall CW, Marchie A, Parker TL, Connelly PW, Qian W, Haight JS, Faulkner D, Vidgen E, Lapsley KG, Spiller GA. Dose response of almonds on coronary heart disease risk factors: blood lipids, oxidized low-density lipoproteins, lipoprotein(a), homocysteine, and pulmonary nitric oxide: a randomized, controlled, crossover trial. Circulation 2002;106:1327–1332.

Jenner JL, Jacques PF, Seman LJ, Schaefer EJ. Ascorbic acid supplementation does not lower plasma lipoprotein(a) concentrations. Atherosclerosis 2000 Aug;151(2):541–544.

Jones PH, Pownall HJ, Patsch W et al. Effect of gemfibrozil on levels of lipoprotein(a) in Type II hyperlipoproteinemic subjects. J Lipid Res 1996;37:1298–1308.

Kikuchi T, Onuma T, Shimura M et al. Different change in lipoprotein(a) levels from lipid levels of other lipoproteins with improved glycemic control in patients with NIDDM. Diabetes Care 1994 Sep;17(9):1059–1061.

Kiortsis DN, Tzotzas T, Giral P et al. Changes in lipoprotein(a) levels and hormonal correlations during a weight reduction program. Nutr Metab Cardiovasc Dis 2001 Jun(3):153157.

Kroon AA, Demacker PN, Stalenhoef AF. N-acetylcysteine and serum concentrations of lipoprotein(a). J Intern Med 1991 Dec; 239(6):519–526.

Maher VM, Brown BG, Marcovina SM et al. Effects of lowering elevated LDL cholesterol on the cardiovascular risk of lipoprotein(a). JAMA 1995 Dec 13;274(22):1771–1774.

Marth E, Cazzolato G, Bittolo Bon G, Avogaro P, Kostner GM. Serum concentration of Lp(a) and other lipoprotein parameters in heavy alcohol consumers. Nutr Metab 1982;26:56–62.

Marcovina SM, Kennedy H, Bittolo Bon G et al. Fish intake, independent of apo(a) size, accounts for lower plasma lipoprotein(a) levels in Bantu fishermen of Tanzania: The Lugalawa Study. Arterioscler Thromb Vasc Biol 1999 May;19(5):1250–1256.

Marcovina SM, Lippi G, Bagatell CJ, Bremner WJ. Testosterone-induced suppression of lipoprotein(a) in normal men; relation to basal lipoprotein(a) level. Atherosclerosis 1996 Apr 26;122(1):89–95.

Martinez-Triguero ML, Hernandez-Mijares A, Nguyen TT et al. Effect of thyroid hormone replacement on lipoprotein(a), lipids, and apolipoproteins in subjects with hypothyroidism. Mayo Clin Proc 1998 Sep;73(9):837–841.

Mensink RP, Zock PL, Katan MB, Hornstra G. Effect of dietary cis and trans fatty acids on serum lipoprotein(a) levels in humans. J Lipid Res 1992 Oct;33(10):1493–1501.

Merz-Demlow BE, Duncan AM, Wangen KE, Xu X, Carr TP, Phipps WR, Kurzer MS. Soy isoflavones improve plasma lipids in normocholesterolemic, premenopausal women. Am J Clin Nutr 2000; 71: 1462–1469.

Milionis HJ, Efstathiadou Z, Tselepis AD et al. Lipoprotein (a) levels and apolipoprotein (a) isoform size in patients with subclinical hypothyroidism: effect of treatment with levothyroxine. Thyroid 2003 Apr;13(4):365–369.

Müller H, Lindman AS, Blomfeldt et al. A diet rich in coconut oil reduces diurnal postprandial variations in circulating tissue plasminogen activator antigen and fasting lipoprotein(a) compared with a diet rich in unsaturated fat in women. J Nutr 2003;133:3422–3427.

Nardulli M, Durlach V, Pepe G, Anglés-Cano E. Mechanism for the homocysteine-enhanced antifibrinolytic potential of lipoprotein(a) in human plasma. Thromb Haemostast 2005 Jul;94(1):75–81.

Nilausen K, Meinerrz H. Lipoprotein (a) and dietary proteins: casein lowers lipoprotein (a) concentrations as compared with soy protein. Am J Clin Nutr 1999;69:419–425.

Palmer LA, Doctor A, Chhabra P et al. S-Nitrosothiols signal hypoxia-mimetic vascular pathology. J Clin Invest 2007;117: 2592–2601.

Perez A, Carreras G, Caixas A et al. Plasma lipoprotein(a) levels are not influenced by glycemic control in type 1 diabetes. 1998 Sep;21(9):1517–1520.

Perez A, Khan M, Johnson T, Karunaratne M. Piioglitazone plus a sulphonylurea or metformin is associated with increased lipoprotein particle size in patients with type 2 diabetes. Diabetes Vasc Dis Res
2004;1:44–50.

Randall OS, Feseha HB, Illoh K et al. Response of lipoprotein(a) levels to therapeutic life-style change in obese African-Americans. Atherosclerosis 2004 Jan;172(1):155–160.

Rath M. Lipoprotein(a) by ascorbate. J Orthomol Med 1992 Aug;7(2): 81–82.

Reiner Z, Tedeschi-Reiner E, Romić Z. Effects of rice policosanol on serum lipoproteins, homocysteine, fibrinogen and C-reactive protein in hypercholesterolaemic patients. Clin Drug Investig 2005;25(11):701–707.

Sanders TAB, Oakley FR, Miller GJ et al. Influence of n-6 versus n-3 polyunsaturated fatty acids in diets low in saturated fatty acids on plasma lipoproteins and hemostatic factors. Arterioscl Thrombo Vasc Biol 1997;17:3449–3460.

Shlipak MG, Simon JA, Vittinghoff E et al. Estrogen and progestin, lipoprotein(a), and the risk of recurrent coronary heart disease events after menopause. JAMA 2000 Apr 12;283(14):1845–1852.

Siegel G, Schäfer P, Winkler K, Mainsten M. Ginkgo biloba (EBG 761) in arteriosclerosis prophylaxis. Wien Med Wochenschr 2007;157(13–14):288–294.

Shin MJ, Blanche PJ, Rawlings RS, Fernstrom HS, Krauss RM. Increased plasma concentrations of lipoprotein(a) during a low-fat, high-carbohydrate diet are associated with increased plasma concentrations of apolipoprotein C-III bound to apolipoprotein B-containing lipoproteins. Am J Clin Nutr 2007 Jun;85(6):1527–1532.

Silaste M, Rantala M, Alfthan G et al. Changes in dietary fat intake alter plasma levels of oxidized low-density lipoprotein and lipoprotein(a). Arterioscler Thromb Vasc Biol;24:498–503.

Sirtori CR, Calabresi L, Ferrara S, Pazzucconi F, Bondioli A, Baldassarre D, Birreci A, Koverech A. L-carnitine reduces plasma lipoprotein(a) levels in patients with hyper Lp(a). Nutr Metab Cardiovasc Dis 2000;10:247–251.

Solfrizzi V, Panza F, Colacicco AM et al. Relation of lipoprotein(a) as coronary risk factor to type 2 diabetes mellitus and low-density lipoprotein cholesterol in patients ≥65 years of age (The Italian Longitudinal Study on Aging). Am J Cardiol 2002;89:825–829.

Sotirou SN, Orlova VV, Al-Fakhri N et al. Lipoprotein(a) in atherosclerotic plaques recruits inflammatory cells through interaction with Mac-1 integrin. FASEB J 2006 Mar;20(3):559–561.

Teede HJ, Dalais FS, Kotsopoulos D et al. Dietary soy has both beneficial and potentially adverse cardiovascular effects: a placebo-controlled study in men and postmenopausal women. J Clin Endocrinol Metab 2001 Jul;86(7):30533060.

Tonstad, S, Smerud K, Hoie L. A comparison of the effects of 2 doses of soy protein or casein on serum lipids, serum lipoproteins, and plasma total homocysteine in hypercholesterolemic subjects. Am J Clin Nutr 2002 Jul;76(1):78–84.

Välimeli M, Laithinen K, Ylikahri C, Ehnholm C, Jauhiainen M, Bard JM, Fruchart JC, Taskinen MR. The effect of moderate alcohol intake on serum apolipoprotein A-I-containing lipoproteins and lipoprotein(a). Metabolism 1991;40:1168–1172.

Van Wissen S, Smilde TJ, Trip MD et al. Long term statin treatment reduces lipoprotein(a) concentrations in heterozygous familial hypercholesterolaemia. Heart 2003;89:893–896.

Velazquez EM Mendoza SG, Wang P, Glueck CJ. Metformin therapy is associated with a decrease in plasma plasminogen activator inhibitor-1, lipoprotein(a), and immunoreactive insulin levels in patients with the polycystic ovary syndrome. Metabolism 1997 Apr;46(4):454–457.

Vessby B, Unsitupa M, Hermansen K et al. Substituting dietary saturated for monounsaturated fat impairs insulin sensitivity in healthy men and women: The KANWU Study. Diabetologia 2001 Mar;44(3):312–319.

Wiklund O, Fager G, Andersson A et al. N-acetylcysteine treatment lowers plasma homocysteine but not serum lipoprotein(a) levels. Atehrosclerosis 1996 Jan 5;119(1):99–106.

Wood RJ, Volek JS, Davis SR et al. Efects of a carbohydrate-restricted diet on emerging plasma markers for cardiovascular disease. Nutr Metab 2006;3:19.

Zmuda JM, Thompson PD, Dickenson R, Bausserman LL. Testosterone decreases lipoprotein(a) in men. Amer J Cardiol 1996 (June);77:1244–1247.