Researchers have found a clue that flavorings in e-cigarettes may be bad for the heart. Dr. Joseph Wu of Stanford University and his team grew cells that normally line healthy human blood vessels. They exposed the cells to six different e-cigarette flavorings. Vaping and some flavorings, even without nicotine, triggered blood vessel dysfunction, the researchers reported in the Journal of the American College of Cardiology. Cinnamon and menthol seemed the most toxic. But overall, cells showed signs of damage and were inflamed, less able to form new blood vessels or heal wounds.

Blueberries show metabolic benefits

A study in the American Journal of Clinical Nutrition found that participants with metabolic syndrome who consumed the equivalent of one cup of blueberries, given as 26g of freeze-dried blueberries, showed improvements in heart health, particularly in markers of vascular function. It also resulted in increased HDL levels, known as "good cholesterol," compared to a placebo. The study — a 6-month, double blind, randomized trial — was conducted at the University of East Anglia in collaboration with Harvard T.H. Chan School of Public Health. It was funded by the U.S. Highbush Blueberry Council, which had no role in the study.

Teens cite constant use of mobile devices

Four out of five teenagers with mobile devices keep them in their rooms overnight — and nearly a third of those bring them to bed — said a study that offered the most comprehensive picture yet of the devices' impact on teen sleep patterns. The study was based on a poll of 1,000 children and parents by consumer advocacy group Common Sense. The screens' blue light has been associated with poor sleep, researchers say, but the devices also can cause emotional stimulation that also can impair or delay sleep. Poor sleep patterns can undermine cognitive functioning and mental health while increasing obesity rates.

News services