New studies add life-saving luster to two vital foods 02/05/2004
Fish oils ameliorate teen anger, and heart risks in adulthood
A study published earlier this month indicates that teens whose diets are high in fish or DHA—an omega-3 fatty acid found only in fish oils—enjoy lower hostility levels and a reduced risk of coronary artery disease.
The researchers analyzed the diets and behavior of about 3,600 city-dwelling adolescent boys and girls (white and black).
Cold-water fish species offer the highest levels of omega-3s (DHA and EPA)—and wild salmon contains more of them than most.
Blueberries found helpful to arteries and heart health
It seems that the blueberry-loving bears of Maine and Alaska are onto something big.
The study showed that the arteries of lab rats fed a diet high in wild blueberries remain more relaxed in response to stress hormones, compared with rats on otherwise identical berry-free diets.
As lead author Dorothy Klimis-Zacas, Ph.D., associate professor at the University of Maine said, "We know now that blueberries affect the contractile machinery of the artery."
While the researchers did not identify the nutritional factors that kept arteries more relaxed, they hypothesized that blueberries' high concentrations of antioxidants and trace minerals (e.g., manganese) are likely responsible.
After performing experiments on the inner surface of the artery, the authors concluded that the blueberry-rich diets probably produced their benefit by preserving the bio-availability of nitric oxide—a bodily chemical that helps to relax the arteries.
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