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Omega-3s Have Positive Effects on Heart, Muscle Anabolism and Fat Burning
by: Anssi Manninen, M.H.S.

Reproduced, with permission, from Musclar Development

The human body needs fatty acids, and it can make all but two of them: linoleic acid (omega-6 fatty acid) and linolenic acid (omega-3 fatty acid). Given linolenic acid, the body can make the 20 and 22-carbon members of the omega-3 series, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). These omega-3 fatty acids are absolutely critical for normal growth and development and they play a very important role in the prevention and treatment of diseases. It should be noted, however, that only a small amount of linolenic acid is converted to DHA, and linolenic acid does not raise blood DHA levels. One of the primary reasons linolenic acid is so poorly converted to EPA and DHA is that it is mostly burned for energy.

Fish Oil is Heart-Healthy

Fish, especially oily species like mackerel, lake trout, herring and sardines, provide significant amounts of EPA and DHA. A growing body of evidence indicates that EPA and DHA can help to:

  • decrease risk for arrhythmias (an alteration in rhythm of the heartbeat), which can lead to sudden cardiac death.
  • decrease risk for thrombosis (the formation or presence of a blood clot within a blood vessel), which can lead to heart attack and stroke.
  • decrease triglyceride and remnant lipoprotein levels.
  • decrease the rate of growth of atherosclerotic plaque.
  • improve endothelial function.
  • reduce inflammatory responses.

It is very important to realize that only omega-3 fatty acids from fish oil have cardio-protective properties. A systematic review published in The American Journal of Clinical Nutrition concluded that “Increased consumption [of omega-3 fatty acids] from fish or fish-oil supplements, but not of [linolenic acid], reduces the rates of all-cause mortality, cardiac and sudden death, and possibly stroke.”

The cardio-protective effects of fish oil are especially important for those abusing anabolic steroids. Clearly, anabolic steroid use (especially in high doses) has some adverse effects on heart and blood vessels. However, I am certainly not suggesting that one can eliminate the potential adverse effects by simply taking in fish oil. Rather, fish oil may help to decrease the risks. Regular cardiovascular training is important too.

Fish Oil Increases Muscle Anabolism

There is some evidence that fish can improve insulin sensitivity. So, a recent study at the Department of Animal Science of Laval University in Canada investigated its potential role in regulating insulin-mediated protein metabolism. They added supplements containing either omega-3 fatty acids from fish oil or a mixture of cotton seed and olive oils without omega-3s to the regular diet of steers. After five weeks, animals with the omega-3 diet showed increased sensitivity to insulin which, in turn, increased protein anabolism. In fact, twice the amount of amino acids was used by their bodies to synthesize proteins, especially in skeletal muscles. One of the researchers, Dr. Carole Thivierge, suggested that omega-3 fatty acids could help athletes trying to increase their muscle mass.

Fish Oil Increases Fat Burning During Exercise

Omega-3 fatty acids can be incorporated into the membrane of red blood cells, making these cells less viscous and less resistant to flow. Less viscous red blood cells and the vasodilative effect may enhance blood flow, facilitating the delivery of blood (and thus oxygen and nutrients) to the muscle. A study by Dr. Derek Huffman and colleagues at the University of Missouri, Columbia, examined the effect of an acute high dose and a chronic low dose of fish oil on fat oxidation burning during exercise. While the acute high dose fish oil had no significant effect on fat use during exercise, chronic supplementation significantly augmented total fat energy expenditure. Thus, fish oil supplementation may help shred extra lard in the long run.

Textbook Baloney

A poorly written nutrition textbook, proudly titled Understanding Nutrition, claims that “Fish oil supplements are not recommended for a number of reasons… Fish oil supplements are made from fish skin and livers, which may contain environmental contaminants.” This statement is clearly fallacious. Fish oil capsules contain no mercury. Mercury is water-soluble, not oil-soluble, so when the oil is extracted from the fish, the mercury (and other heavy metals) stays behind in the fish meat. Organic pollutants are potentially another concern. However, fish oil concentrates, the most commonly used supplements, are not derived from the liver of fish, but from the muscle, and so they are lower in pollutants than liver oils. For example, Consumer Reports wrote, “Our tests of 16 top-selling fish-oil supplements were reassuring: All those pills contained roughly as much EPA and DHA as their labels promised. None showed evidence of spoilage, and none contained significant amounts of mercury, the worrisome PCBs, or dioxin.”

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1. Gingrass AA et al. Long-chain omega-3 fatty acids regulate bovine whole-body protein metabolism by promoting muscle insulin signalling to the Akt-mTOR-S6K1 pathway and insulin sensitivity. J Physiol. 2007 Feb 15;579(Pt 1):269-84.

2. Wang C et al. n-3 Fatty acids from fish or fish-oil supplements, but not alpha-linolenic acid, benefit cardiovascular disease outcomes in primary- and secondary-prevention studies: a systematic review. Am J Clin Nutr. 2006 Jul;84(1):5-17.

3. Huffman DM et al Chronic supplementation with fish oil increases fat oxidation during exercise in young men. J Exerc Physiol 2004;7:48-56.