MERCURY EXPOSURE LINKED TO RAISED DIABETES RISK

High blood mercury levels have been known to present a danger to developing fetuses and young children but new research - the first to link mercury and diabetes in humans - suggests that even moderate levels of blood mercury may increase adult’s risk of developing type 2 diabetes.  Researchers found that young adults who have higher levels of mercury in their systems may face a 65% increased risk of developing type 2 diabetes later in life.

The study tracked nearly 3,900 men and women between the ages of 20 and 32 for years.  At the start of the study participants were ages 20-32 and free of diabetes.   Mercury levels in their toenails were measured at the start of the study and then participants were tested for diabetes periodically throughout the study.  The main source of mercury in the diet is from seafood.  Not surprisingly, study participants with the highest levels of blood mercury reported higher intakes seafood.

These findings suggest all persons, not just pregnant mothers and young children, be mindful of their intake of fish containing high levels of mercury.  However, it would be a mistake to avoid all seafood because of mercury.  There is ample evidence that consuming more fish, especially fattier types of fish rich in essential omega-3 fatty acids, is associated with better health and longevity.  For example, a recent study that tracked 2700 older Americans over 16 years, found that those with the highest levels of omega-3 fatty acids in their blood were less likely to die from a range of causes (and especially heart disease) than those with the lowest levels.  On average, those with the highest levels of omega-3 fatty acids, lived two years longer than those with the lowest levels.

What to do:  Seafood is great source of lean protein, minerals and vitamins, and omega-3 fatty acids.  Aim to consume seafood at least twice a week.  Choose seafood that is rich in omega-3 fatty acids but low in mercury including salmon, herring, halibut, and sardines.  Fish that are highest in mercury include king & Spanish mackerel, swordfish, marlin, orange roughy, sea bass, shark, and tuna (skipjack & chunk light are lower).

Adapted from articles available at:

http://www.nlm.nih.gov/medlineplus/news/fullstory_135680.html

http://www.nlm.nih.gov/medlineplus/news/fullstory_135564.html

Sources:

He K, Xun P, Liu K, et al. Mercury exposure in young adulthood and incidence of diabetes later in life: The CARDIA trace element study. Diabetes Care, 2013.  Available at:  http://care.diabetesjournals.org/content/early/2013/02/14/dc12-1842.

Mozaffarian D, Lemaitre RN, King IB, et al. Long-chain ω-3 fatty acids and total and cause-specific mortality in older adults:  A cohort study. Annals of Internal Medicine, 2013 Apr;158(7):515-525.  Available at: http://annals.org/article.aspx?articleid=1671714.