Research on omega-3 fish oils keeps looking better and better: new studies have found that omega-3s fish oils can help with three catastrophic diseases -- Alzheimer's, heart failure, and cancer.
Ernst J. Schaefer, MD, of the USDA's nutrition research center at Tufts University, Boston, analyzed levels of omega-3s and the risk of dementia, including Alzheimer's disease. He and his colleagues measured blood levels of docosahexaenoic acid (DHA, one of the principal omega-3s in fish) in 899 elderly men and women. More than half of the subjects also completed dietary questionnaires, which were used to assess intake of DHA and fish.
Over nine years, 99 of the subjects developed dementia. Schaefer determined that people with the highest blood levels of DHA were about half as likely to develop dementia, compared with people who consumed little DHA. They were also 39 percent less likely to develop Alzheimer's disease.
People with the highest DHA levels consumed about three servings of fish each week, which provided the equivalent of 180 mg of DHA daily.
Fats form about 50 percent of the brain's nonwater weight, and DHA is the predominant fat found in cell membranes of the brain's gray matter.
In a separate study, Alberto U. Ferrari, MD, of the University of Milano-Bicocca, Milan, Italy, treated 25 heart failure patients with beta-blocker and ACE-inhibitor drugs. All of the patients had previously suffered a heart attack that left them with a weakened ability to pump blood.
Fifteen of the patients were also given 2 grams of omega-3 fish oils daily, and 10 received placebos daily for four months. The fish oil supplements contained about three-fifths DHA and two-fifths eicosapentaenoic acid (EPA, another omega-3 fat).
The omega-3s improved the patients' "baroflex sensitivity," leading to a more stable heart rate, less variability in heart rate, and lower resting heart rate. The benefits, Ferrari noted, were above and beyond the improvements achieved with the medications.
Finally, Alicja Wolk, DMSc, of the Karolinska Institute, Stockholm, Sweden, and her colleagues analyzed the relationship between consumption of fish rich in omega-3 fats and the risk of kidney cancer in women. They drew on data from an ongoing study of more than 61,000 middle-age and elderly women whose health was tracked for an average of 15 years. (www.inflammationsyndrome.com)
Women who consumed one or more servings of fatty fish per week were 44 percent less likely to develop kidney cancer, compared with women who did not eat fish. Women who consumed one or more servings of fatty fish per week for at least 10 years were 74 percent less likely to develop kidney cancer.
Schaefer EJ, Bongard V, Beiser AS, et al. Plasma phosphatidylcholine docosahexaenoic acid content and risk of dementia and Alzheimer's disease. Archives of Neurology, 2006;63:1545-1550.
Radaelli A, Cazzaniga M, Viola A, et al. Enhanced baroreceptor control of the cardiovascular system by polyun-saturated fatty acids in heart failure patients. Journal of the American College of Cardiology, 2006; 48:1600-1606.
Wolk A, Larsson SC, Johansson JE, et al. Long-term fatty fish consumption and renal cell carcinoma incidence in women. JAMA, 2006;296:1371-1376.
About the author
Jack Challem, known as The Nutrition Reporter(tm), is a personal nutrition coach based in Tucson, Arizona. Jack is one of America's most trusted nutrition and health writers, and has written about research on nutrition, vitamins, minerals, and herbs for more than 30 years. He is the author of The Food-Mood Solution: The Nutrition and Lifestyle Plan to Feel Good Again (Wiley, 2007), Feed Your Genes Right (Wiley, 2005), The Inflammation Syndrome (Wiley, 2003) and the lead author of the best-selling Syndrome X: The Complete Nutritional Program to Prevent and Reverse Insulin Resistance (Wiley, 2000). His next book, Stop Prediabetes Now, will be published in the fall of 2007. He writes The Nutrition Reporter(tm) newsletter and contributes regularly to many magazines, including Alternative Medicine, Better Nutrition, Body & Soul, Experience Life, and Let's Live. Jack's scientific articles have appeared in Free Radical Biology & Medicine, Journal of Orthomolecular Medicine, Medical Hypotheses, and other journals. In addition, he is a columnist for Alternative & Complementary Therapies. Jack is a frequent speaker at nutritional medicine conferences and to consumer health groups. Email him via www.foodmoodsolution.com