In the News:
Omega-3s & IHD in Women; Physicians’ Supplement Use; B-Vitamins & Mental Function

Long Chain Omega-3s Lower IHD Risk

There are different members of the omega-3 family of fatty acids. One member, called alpha-linolenic acid, can be converted to the longer chain omega-3s EPA and DHA which are found in cold-water fish. However, the conversion of alpha-linolenic acid to EPA/DHA is limited, with only about 8-20% actually converted.

Present in flaxseeds and other plant sources, alpha linolenic acid may not be the best omega-3 choice for heart health in women according to results of a newly published trial (1).

In this prospective Danish study, dietary intake data was analyzed from over 3,200 healthy volunteers. During 23 years of study, 471 cases of ischemic heart disease (IHD) occurred.

IHD, the most common type of cardiovascular disease, refers to problems with the circulation of blood to the heart muscle. A partial blockage of one or more of the coronary arteries can result in too little oxygenated blood (ischemia), thus causing symptoms such as chest pain or shortness of breath. A complete blockage of an artery can cause a heart attack.

The researchers found that high intakes of EPA and DHA were associated with a 38% reduction in IHD risk for women. In contrast, high intakes of alpha-linolenic acid did not significantly lower the risk of IHD among women.

Do Physicians Use Supplements?

According to a newly published survey (2), a majority of US physicians within certain medical specialties appear to use supplements and recommend them to their patients.

Nine hundred physicians were surveyed; 300 cardiologists, 300 orthopedists, and 300 dermatologists. The survey results obtained were in line with the prevalence of use reported among the general public in the most recent National Health and Nutrition Examination survey, where 54% of adults said they had taken supplements in the past month.

Fifty-seven percent of cardiologists said they use dietary supplements at least occasionally, as did 75% of dermatologists and 73% of orthopedists. Regular dietary supplement use was reported by 37% of cardiologists, 59% of dermatologists, and 50% of orthopedists.

The product most commonly reported to be used was a multivitamin, but over 25% in each specialty said they used omega-3 fatty acids and over 20% said they used some botanical supplements. Seventy-two percent of cardiologists, 66% of dermatologists, and 91% of orthopedists reported recommending supplements to their patients.

B-vitamins May Slow Mental Decline

In the February issue of Staying Healthy (Protecting our Brain: Recent Research), scientists reported that a daily combination of folic acid and vitamins B6 and B12 slowed the rate of brain shrinkage or atrophy in people with mild cognitive impairment (MCI). Brain atrophy is a common sign of MCI, and can be an early warning to signs of dementia.

In a follow-up report, the Oxford and Oslo-based researchers looked specifically at participants in this intervention trial who had elevated homocysteine levels at the study’s start. Two years of B-vitamin treatment reduced levels of this amino acid, which has been previously linked to dementia.

Compared to placebo takers, people in the B-vitamin group with high initial homocysteine levels fared better on mental tests such as correct word recall, semantic memory (which refers to meaning, understanding and other concept-based knowledge), and global cognition which tests a range of cognitive functions.

References

1. Sadowa Vedtofte M, et al. Dietary alpha-linolenic acid, linoleic acid, and n-3 long-chain PUFA and risk of ischemic heart disease. Am J Clin Nutr 94:1097-103, 2011.
2. Dickenson A, et al. Use of dietary supplements by cardiologists, dermatologists and orthopedists: report of a survey. Nutr J 10:20, 2011.
3. De Jager CA, et al. Cognitive and clinical outcomes of homocysteine-lowering B-vitamin treatement in mild cognitive impairment: a randomized controlled trial. Int J of Geriatric Psych [Epub ahead of print] July, 2011.