Omega 3s - The Anabolic Stimulators
In December last year, I had the opportunity to attend the International Sport and Exercise Nutrition Conference (ISENC) 2015 in Newcastle (UK), where the latest research in sports and exercise nutrition was shared by leading experts. It was a very comprehensive conference with topics ranging from carbohydrate periodisation in sport, managing weight-related issues in athletes, understanding popular diets such as Paleo and Low-Carb, High-Fat, the benefits of using social media to promote new ideas in sports and exercise nutrition, the importance of omega 3s for health and performance, and many more. The last topic was one of my favourites, not only because I have a personal interest – I love oily fish! – but also because the speakers, Dr Oliver Witard and Dr Lee Hamilton, were simply brilliant in the way they presented the most up-to-date research.
The reason why I love oily fish is because it’s one of nature’s best sources of omega 3s. Plus it’s delicious! Omega 3s and 6s are referred to as ‘essential’ fats because they are needed for our health but our bodies are unable to produce them. The ‘Western’ diet is far richer in omega 6s than omega 3s. This is an increasing concern since an excessive omega 6s to omega 3s ratio (20:1) has been associated with inflammation leading to chronic illness. Having an optimal ratio (2:1) by increasing your omega 3s – particularly EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) – is vital since these are known to be associated not only with cardiovascular health and brain function but also many other benefits, including the prevention of muscle loss.
Prevention of muscle loss is not only relevant in the elderly and people suffering from sarcopenia or cachexia (muscle wasting), but it is also of great importance in athletes for proper muscle function. We all know we need adequate protein intake for our muscles. The problem with simply eating more protein is that it could decrease appetite because it is thought to be the most satiating macronutrient. This may lead to a decrease in energy intake, which is particularly problematic in the elderly. For this reason, researchers have been thinking of ways to increase sensitivity of the muscle to take up more protein and use it to maintain or build muscle mass - a concept known as anabolic sensitivity.
Smith et al. (2015) gave 3.36g/day of fish oil supplementation (equivalent to 200-400g of fish) for six months to healthy elderly men and women (n=29). Compared to a control group (corn oil, n=15), the fish-oil therapy increased thigh volume, handgrip strength and muscle strength. The authors concluded that fish-oil therapy saves two to three years of muscle integrity since, after the age of 40, muscle mass and function typically decline at rates of 1% and 2-3% per year respectively.
In another study, McGlory et al. (2014) gave 5g/day of fish oil supplementation for four weeks to ten healthy young male participants. The supplement was rich in EPA as this is known to be more anabolic than DHA. After four weeks, there was a two-fold increase in the EPA content of the phospholipid layer of the muscle cells and protein synthesis biomarkers had increased. However, in another study (in publication) by the same authors, twenty healthy resistance-trained men were given 5g/day of the same supplement or a placebo control (coconut oil) for eight weeks and showed suppressed protein synthesis in response to resistance training and whey protein feeding. The authors suggest that the physiological relevance of omega 3s may be dependent on context, i.e. the type of muscle stimulation – contraction (through exercise) or nutrition. For example, omega 3s may improve muscle cells’ membrane fluidity, as shown by the greater incorporation of these fatty acids into the membrane in the above four-week study, and so facilitate the transport of nutrients into the cell that subsequently stimulates protein synthesis. However, this change in membrane fluidity may also somehow alter the capacity of skeletal muscle to convert the mechanical tension from the exercise stimulus to a biochemical signal that promotes protein synthesis.
Then again, it is questionable whether coconut oil should be used as a lipid control at all. As it is rich in omega 6s, the results may actually be reflecting those effects. Many other studies have had this problem, which is possibly why trials investigating the effects of omega 3s are negative or not clear-cut. Another potential reason is that many fish oil supplements do not meet the label content of omega 3s and/or include toxic substances, such as dioxins, which could cause more harm than good.
This does not mean that all fish oil supplements are bad, but you do need to make sure that you purchase yours from a reliable source. A better and more delicious option is getting what you need from what you eat - two servings of oily fish a week, such as salmon, mackerel or sardines, should do the trick!!
1. LEIDY, H. J., CARNELL, N. S., MATTES, R. D. & CAMPBELL, W. W. 2007. Higher protein intake preserves lean mass and satiety with weight loss in pre-obese and obese women. Obesity (Silver Spring), 15, 421-9.
2. SMITH, G. I., JULLIAND, S., REEDS, D. N., SINACORE, D. R., KLEIN, S. & MITTENDORFER, B. 2015. Fish oil-derived n-3 PUFA therapy increases muscle mass and function in healthy older adults. Am J Clin Nutr, 102, 115-22.
3. MCGLORY, C., GALLOWAY, S. D. R., HAMILTON, D. L., MCCLINTOCK, C., BREEN, L., DICK, J. R., BELL, J. G. & TIPTON, K. D. Temporal changes in human skeletal muscle and blood lipid composition with fish oil supplementation. Prostaglandins, Leukotrienes and Essential Fatty Acids, 90, 199-206.
4. KAMOLRAT, T. & GRAY, S. R. 2013. The effect of eicosapentaenoic and docosahexaenoic acid on protein synthesis and breakdown in murine C2C12 myotubes. Biochem Biophys Res Commun, 432, 593-8.