Fish oil supplementation - benefits for young healthy adults
Fish oil is well known for protecting against development and progression of cardiovascular disease in high risk individuals, mostly middle-age and older.[1-4] A notable recent study shows that fish oil supplementation also confers health benefits in young healthy adults.
Young healthy males, aged 21-24 years, were given a fish oil supplement providing 2 g EPA and 1 g DHA per day for 3 months. It was found that the fish oil supplementation significantly reduced fasting blood triglycerides (i.e. blood fats) by a whopping 38% (from 86 mg/dL to 54 mg/dL) and also improved the total cholesterol/HDL ratio, by reducing it from 3.25 to 3.05.
Relevance of blood triglycerides and the total cholesterol/HDL ratio for cardiovascular disease
When it comes to heart/cardiovascular disease, historically LDL (aka the "bad cholesterol") has been the focus of attention. However, a scientific statement from the American Heart Association (AHA) highlighted the pivotal role of triglycerides in lipid metabolism and reaffirmed that triglycerides represents an important biomarker of cardiovascular disease risk because of its association with atherogenic lipid particles. AHA states that an optimal fasting triglyceride levels is below 100 mg/dL, and that this is a parameter of good metabolic health. Fasting triglycerides represent a useful marker for risk of coronary heart disease, particularly when HDL levels are low. Elevated triglyceride levels are a component of the metabolic syndrome and are strongly associated with future risk of diabetes as well as cardiovascular disease. Triglyceride-rich particles increase cardiovascular risk above that conferred by LDL, and elevated triglycerides are a marker of atherogenic small dense LDL.
An elevated total cholesterol/HDL ratio (HDL,aka the "good cholesterol") increases heart disease risk independently of LDL  and a high ratio may be a good indicator of abnormal cholesterol metabolism. Each 1-unit increase in the total cholesterol/HDL ratio has been associated with 49% increases in risk of heart attack. Increases in the total cholesterol/HDL ratio has also been associated with substantial deleterious alterations in metabolic indices indicative of the metabolic syndrome.
Thus, lowering of triglyceride levels and reduction of the total cholesterol/HDL ratio with fish oil supplementation in young healthy adults may help keep blood lipids in the optimal range during the life course, and provide protection against future development of cardiovascular disease. And as we all know, prevention is better than treatment.
- Saravanan, P., et al., Cardiovascular effects of marine omega-3 fatty acids. Lancet, 2010. 376(9740): p. 540-50.
- Marik, P.E. and J. Varon, Omega-3 dietary supplements and the risk of cardiovascular events: a systematic review. Clin Cardiol, 2009. 32(7): p. 365-72.
- Kris-Etherton, P.M., W.S. Harris, and L.J. Appel, Fish consumption, fish oil, omega-3 fatty acids, and cardiovascular disease. Circulation, 2002. 106(21): p. 2747-57.
- Lavie, C.J., et al., Omega-3 polyunsaturated fatty acids and cardiovascular diseases. J Am Coll Cardiol, 2009. 54(7): p. 585-94.
- Zulyniak, M.A., et al., Fish oil supplementation alters circulating eicosanoid concentrations in young healthy men. Metabolism, 2013. 62(8): p. 1107-13.
- Miller, M., et al., Triglycerides and cardiovascular disease: a scientific statement from the American Heart Association. Circulation, 2011. 123(20): p. 2292-333.
- Gaziano, J.M., et al., Fasting triglycerides, high-density lipoprotein, and risk of myocardial infarction. Circulation, 1997. 96(8): p. 2520-5.
- Wierzbicki, A.S., et al., Triglycerides: a case for treatment? Curr Opin Cardiol, 2012. 27(4): p. 398-404.
- Arsenault, B.J., et al., Beyond low-density lipoprotein cholesterol: respective contributions of non-high-density lipoprotein cholesterol levels, triglycerides, and the total cholesterol/high-density lipoprotein cholesterol ratio to coronary heart disease risk in apparently healthy men and women. J Am Coll Cardiol, 2009. 55(1): p. 35-41.
- NIH Consensus conference. Triglyceride, high-density lipoprotein, and coronary heart disease. NIH Consensus Development Panel on Triglyceride, High-Density Lipoprotein, and Coronary Heart Disease. JAMA, 1993. 269(4): p. 505-10.
- Lemieux, I., et al., Total cholesterol/HDL cholesterol ratio vs LDL cholesterol/HDL cholesterol ratio as indices of ischemic heart disease risk in men: the Quebec Cardiovascular Study. Arch Intern Med, 2001. 161(22): p. 2685-92.