Combine a world where dictating market forces seek controversy with a subject as nebulous and indefinite as health and you become privy to a myriad of sometimes false, usually dubious, claims of salubrious solutions.
However amidst the dense fog of confusion lies the grounding of some basic and indisputable truths. Eat your veggies, cut down on sugar, exercise more often; these are all examples of statements that your mother would have iterated, and ones that should not go unheeded. And now, a relatively recent ascension to this small heralded group of nutrition dogma is the recommendation for us all to consume oily fish/fish oil supplements.
So it was with much bewilderment that I read the disparaging remarks toward fish oils, reported by the Daily Mail this week, 'Hooked on fish-oil pills? You're wasting your money, says a nutrition expert'.
Instead of fueling their toxic flames through added publicity, I will bypass their erroneous and inane statements which betray a basic knowledge of the physiological and biochemical workings of the body and proceed in providing the other side of the tale, the one backed by hard science.
When it comes to fish oils there is simply no other nutritional supplement that carries its weight with such a consistently supportive evidence base for producing mass reductions in our rampant disease levels. For the three quarters of us in the UK who do not include oily fish as part of our routine dietary habits, supplementing fish oils is the single most important dietary change we can make.
Like motor oil for a car, fish oil is essential for our wellbeing; oiling the heart, brain and joints for increased longevity. The most compulsive evidence (Level - A) exists for their role in cardiovascular disease. Just under 1 gram of EPA/DHA (the omega three fats in fish oil) in a post heart attack population is clinically proven to reduce death, non-fatal heart attack and non-fatal stroke by about 15% [1].
For those of us yet to, and not keen to, experience a heart attack, fish oils stabilise the electrical rhythm of the heart, are anti-thrombogenic, anti-inflammatory and therefore anti-atherogenic, and even have minor anti-hypertensive effects [2]. In a meta-analysis of 19 observational studies fish consumption was associated with a 14% lower risk of coronary heart disease[3].
The effects of fish oils on our lipid profiles are a real 'gotchya' for the pseudo-nutrition scientist. Fish oils modestly raise our 'good' HDL levels, but we also experience a concomitant significant increase in our 'bad' LDL levels also. This prompts warning sirens, with some suggesting that for anyone with raised cholesterol fish oil avoidance is a must.
This could not be further from the truth, and as always the devil is in the detail. When it comes to LDL cholesterol, it is not all made equal differing by its particle size. And it's the small particle LDL that confers the highest atherogenicity risk. Thus, anything which converts small particle LDL to large particle LDL will actually decrease our cardiovascular disease risk despite the overall volume of LDL increasing - think small hard pellets versus buoyant sponge balls smacking of our artery walls. This is exactly what fish oils do.
Not only this, but repeated intervention studies show fish oils dramatically lower our triglyceride levels (~30% reduction in hypertriglyceridemia populations)[4], an often overlooked established risk factor for heart disease. With high sugar intakes having the opposite effect; increasing small particle LDL and triglyceride levels, ensuring we consume our fish oils helps buffer us from the deleterious from the mass refined carbohydrate consumption which now characterises our modern diets.
So compelling are the cardiovascular benefits of fish oils that they are one of the rare nutritional interventions to have a prescriptive medicinal licence, in the form of the product Omacor, for the pharmacological treatment of post myocardial infarction patients (1gram/day) and hypertriglyceridemia (2-4g/day). The American Heart Association recommends all patients with coronary heart disease supplement 1gram/day (as EPA/DHA)[5], and for those looking to ward off the nations biggest killer to consume 500mg/day[6] . With our average consumption a meagre 100-200mg [7], for those not willing to bump their oily fish intake supplementation is a must.
To truly illustrate the essentiality and ubiquitous nature of fish oil in the body, let's briefly review some of its other physiological roles. A new compelling body of data is emerging to suggest that the dearth of oily fish from our diet has a significant role to play in the exponential rise of mental illness - now the single greatest burden of all human disease. Fish oils are critical for the structural functioning of the brain as well as being involved in neurotransmitter activity.
A recent meta-analysis of 15 randomised controlled trials fish oils in major depression found significant benefit when the fish oil EPA was given in daily doses between 200mg -2,200mg/day in excess of DHA - achieved by one gram of standard fish oil consumption [8]. New research is also emerging for the role of the fish oil DHA in staving off Alzheimer's disease, prompting experts to endorse fish oil supplements in 'individuals who are looking for ways to maintain their cognitive function as they age' [9].
It's an impressive resume, and we have not even had time today to encroach upon its role in quenching inflammation making it a therapeutic strategy in such diverse conditions as neurodegenerative diseases, obesity, type 2 diabetes, rheumatoid arthritis, and even cancer to name just a few [10, 11].
So there you go, fish oils, the uncut version, nutritional wonder or mere snake oil? I know which option smells fishy to me.
1. Dietary supplementation with n-3 polyunsaturated fatty acids and vitamin E after myocardial infarction: results of the GISSI-Prevenzione trial. Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto miocardico. Lancet, 1999. 354(9177): p. 447-55.
2. Grundy, S.M., N-3 fatty acids: priority for post-myocardial infarction clinical trials. Circulation, 2003. 107(14): p. 1834-6.
3. Whelton, S.P., et al., Meta-analysis of observational studies on fish intake and coronary heart disease. Am J Cardiol, 2004. 93(9): p. 1119-23.
4. Miller, M., et al., Triglycerides and cardiovascular disease: a scientific statement from the American Heart Association. Circulation, 2011. 123(20): p. 2292-333.
5. 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.
6. ISSFAL Statement 2004 - http://archive.issfal.org/index.php/lipid-matters-mainmenu-8/issfal-policy-statements-mainmenu-9/23-issfal-policy-statement-3.
7. Kris-Etherton, P.M., et al., Polyunsaturated fatty acids in the food chain in the United States. Am J Clin Nutr, 2000. 71(1 Suppl): p. 179S-88S.
8. Sublette, M.E., et al., Meta-analysis of the effects of eicosapentaenoic acid (EPA) in clinical trials in depression. J Clin Psychiatry, 2011.
9. Fotuhi, M., P. Mohassel, and K. Yaffe, Fish consumption, long-chain omega-3 fatty acids and risk of cognitive decline or Alzheimer disease: a complex association. Nat Clin Pract Neurol, 2009. 5(3): p. 140-52.
10. Chapkin, R.S., et al., Dietary docosahexaenoic and eicosapentaenoic acid: emerging mediators of inflammation. Prostaglandins Leukot Essent Fatty Acids, 2009. 81(2-3): p. 187-91.
11. Goldberg, R.J. and J. Katz, A meta-analysis of the analgesic effects of omega-3 polyunsaturated fatty acid supplementation for inflammatory joint pain. Pain, 2007. 129(1-2): p. 210-23.