Nutritional Supplements for Older Adults: Review and Recommendations—Part II

Abstract

The use of nutritional supplements (NS) with the intention of improving health and delaying age-related chronic disease is a common practice among older adults; however, randomized controlled trials have yielded mixed results regarding the likelihood that these NS provide true health benefits. We reviewed the findings of these studies regarding the effects of NS of folic acid, vitamin B₁₂, vitamin B₆, and omega-3 fatty acids on health outcomes in older adults. Our conclusions include the following: Supplements of the B vitamins folate, B₁₂ and B₆ have been studied with regards to primary and secondary prevention of a number of major age-related chronic diseases, including cardiovascular disease (CVD), stroke, cognitive decline, and cancer. While there are some encouraging findings with regards to stroke, depression, and macular degeneration (although in only one study in the latter case), there is little evidence of benefit of B vitamin NS for delaying CVD or age-related cognitive changes. In the few cancer-related studies, the evidence of benefit is coupled with concerns about enhancing the growth of existing undiagnosed cancers. In contrast, clear health benefits have been shown with modest increases in consumption of fatty fish or fish oil supplements, including a reduction in the risk of sudden cardiac death. In addition, there is evidence that high dose fish oil supplements may lower serum triglyceride levels.

KEYWORDS:

• fish oils
• folate
• folic acid
• health outcomes
• older adults
• omega-3 fatty acids
• supplements
• vitamin B₆
• vitamin B₁₂

Notes

*NHANES III, 1988–1994 except where otherwise indicated.

†Data shown here for folate are from NHANES III 1999, reflecting reported intakes in the post fortification period (115). In a follow-up study by Lewis et al. NNANES folate intakes were corrected for the higher bioavailability of synthetic folic acid in supplements and fortified foods and were found to be as high as 708 µg/day in men aged 45–69yrs (116).

‡ND = Cannot be determined due to lack of data of adverse effects in this age group.

^§The FDA has ruled that intakes up to 3 g/day of marine omega-3 fatty acids are GRAS (Generally Recognized As Safe) (117).

ASFAST: Atherosclerosis and Folic Acid Supplementation Trial. CKD: Chronic Kidney Disease. CVD: Cardiovascular Disease. ESRD: End Stage Renal Disease. HOPE-2: Heart Outcomes Prevention Evaluation Trial. HOST: Homocysteinemia in Kidney and End Stage Renal Disease. MI: Myocardial Infarction. NORVIT: Norwegian Vitamin Trial. WAFACS: Women's Antioxidant and Folic Acid Cardiovascular Study. WENBIT: Western Norway B-Vitamin Intervention Trial. VISP: Vitamins Intervention for Stroke Trial.

*Terminated early because of possible adverse effects based on reports from a contemporaneous study.

AFPPS: Aspirin/Folate Polyp Prevention Study. CVD: Cardiovascular Disease. HPFS: Health Professions Follow-Up Study. MI: Myocardial Infarction. NHS: Nurses' Health Study. NORVIT: Norwegian Vitamin Trial. ukCAP: United Kingdom Colorectal Adenoma Prevention. WAFACS: Women's Antioxidant and Folic Acid Cardiovascular Study. WENBIT: Western Norway B-Vitamin Intervention Trial.