In the News: Anti-aging effects of Blueberries, Omega-3s & Salt Reduction

Can Blueberries Aid Memory in Older Adults?

The Blueberry – and its Scandinavian counterpart, the Bilberry – are rich sources of flavonoids, particularly the kind known as anthocyanins. Researchers have long been interested in the effects of these flavonoids on brain functioning. Studies, for example, have shown positive mental gains in older animals when blueberries were added to their diet. [See: Staying Healthy, Jan, 2008 at sciencebasedhealth.com]. Now, results from a small pilot study conducted by the US Department of Agriculture and Tufts University suggest that these berries may support brain function in people too (1).

In this study, the first of its kind, older people with early memory problems and an increased risk of dementia and Alzheimer’s, took a daily drink of about 500 ml (17 ounces) of blueberry juice for a 3 month period. Results showed significant improvements in learning and word-list recall, a measure of short-term memory. A trend toward reduced symptoms of depression was also observed.

While the investigators stressed that these findings need to be confirmed in a larger and controlled trial, they were encouraged that consistent supplementation with blueberries could be a way to forestall brain aging. It’s believed that the flavonoids in blueberries and bilberries may enhance connections and communication between nerve cells, and stimulate nerve cell regeneration.

Omega-3 Linked to Younger Biological Age

Telomeres are the genetic material at the end of chromosomes that shorten as cells replicate (the process by which cells divide and make copies of themselves). With each replication telomeres get shorter, and when they are used up, the cells are destroyed. Many experts believe that telomere length may be a marker of biological aging.

Previous studies have shown that telomeres are vulnerable to oxidative stress, and certain antioxidant nutrients have been linked to maintaining telomere length. [See: Staying Healthy, Nov, 2009].

Researchers from the University of California, San Francisco recently reported that higher blood levels of the omega-3 fatty acids EPA and DHA are linked to a lower rate of telomere shortening over a 5 year period in people with stable coronary artery disease (2). Telomeres shortened more rapidly in those with the lowest blood levels of EPA and DHA, while they grew shorter more slowly in those with the highest levels of these 2 fatty acids. Omega-3s have been shown to reduce markers of oxidative stress and increase levels of antioxidant enzymes, which may account for their protective effect.

The researchers noted that several studies have shown that high dietary intake of marine omega-3s is associated with longer survival in people with cardiovascular disease. While it’s not established that the omega-3 and telomere connection plays a role in the better survival rate, it could be a contributing factor.

Less Salt, Big Benefits

A new report published in the New England Journal of Medicine concludes that lowering the amount of salt people eat by even a small amount could meaningfully reduce cases of heart disease, stroke and heart attacks (3). The report found that everyone would benefit from less salt, but people at higher risk for heart problems would benefit the most. If everyone consumed even ½ a teaspoon less salt daily, there would be between 54,000 and 99,000 fewer heart attacks each year according to the estimates.

The idea that only certain people need to limit salt is a misconception, since blood pressure increases with age. Nearly 1/3 of adults have hypertension, and another 1/3 currently have pre-hypertension. To cut back on salt intake use the salt shaker less, and more importantly, read the sodium content on labels of processed foods – the source of about 75% of our dietary salt intake.

References

1. Krikorian R, et al. Blueberry supplementation improves memory in older adults. J Agri Food Chem, Epub Jan 4, 2010.
2. Farzaneh-Far R, et al. Association of marine omega-3 fatty acid level with telomeric aging in patients with coronary heart disease. J American Medical Assoc 303:250-7, 2010.
3. Bibbins-Domingo K, et al. Projected effect of dietary salt reductions on future cardiovascular disease. N Engl J Med, Epub Jan 20, 2010.