Higher Intakes of Omega-3 Fatty Acids Associated with Lowered Risk for Lou Gehrig’s Disease
Fitzgerald, K. C. et al., JAMA Neurology, 71: 1102-1110, 2014
Department of Nutrition, Harvard School of Public Health, Boston, Mass., USA
Amyotrophic lateral sclerosis (ALS) is known also as Lou Gehrig’s disease. It is a very serious motor neuron disease characterized by progressive weakness resulting from muscle weakness general leading to survival durations of less than five years following onset. Since the intake of EPA/DHA omega-3 fatty acids have been found to offer neuroprotective benefit in some animal models of aging and other neurodegenerative conditions, the aim of the present study was to study the relationship of long-chain polyunsaturated fatty acid intakes to the risk of developing ALS.
For this purpose, the outcomes of just over one million subjects (free of ALS at the beginning of follow-up) from 5 prospective cohort studies were followed for 9-24 years. Across these combined studies, 995 cases of ALS were subsequently documented. After adjusting the results for confounding variables (age, smoking status, physical activity, education, body mass index, others) , the overall ‘multivariate-adjusted’ risk for developing ALS was found to be significantly lower (by 34 %) in those with the highest intake (top 20 % of the population) of total omega-3 fatty acids as compared to those with the lowest intakes (bottom 20 %). Breaking the omega-3 intakes into the short-chain (as LNA, alpha-linolenic acid) or long-chain (EPA/DHA from marine sources) categories indicated that consuming both types at the highest dietary levels (relative to the lowest) were associated with 27 % and 16 % lower risks, respectively, for developing ALS. The authors concluded that the consumption of food sources high in omega-3 fatty acids ‘may help prevent or delay the onset of ALS’.
The highest median intakes of total omega-3 fatty acids, LNA omega-3 , or EPA/DHA omega-3 that were associated with the lowest risks of developing ALS were 2.11 grams , 1.93 grams, and 300 milligrams, respectively. The current average North American intake of LNA (mainly from plant-based foods sources such as soybean/canola oils, seeds, nuts) is approx. 1.5 grams/day while that for EPA/DHA (mainly from fish/seafood) is only approx. 120 milligrams /person daily. The latter would need to be increased by 150 % to approach an intake of 300 milligrams/person/day. This could be reached in most individuals by consuming two portions/week of relatively fatty fish such as is typically consumed in North America and/or via supplementation and/or via the ingestion of selected foods enriched in EPA/DHA.