Health Buzz: HIV Testing for Teens and Other Health News

CDC Says Teens Need HIV Testing; Half of HIV-Positive Teens Don' t Know They're Infected

 Almost 50 percent of HIV-positive American teens and young adults don't know they are infected, according to data from the U.S. Centers for Disease Control and Prevention. In today's issue of the CDC's Morbidity and Mortality Weekly Report, data from a 2007 survey of high school students showed that only 22 percent of those who were sexually active got tested for HIV. Students were more likely to get HIV testing if they had learned about AIDS or HIV infection in school, Reuters reports.

The report's release comes just before the U.S. National HIV Testing Day on June 27, a date on which HIV testing sites, health departments, and healthcare providers hold special events to teach the importance of HIV testing. As many as 1 million Americans are infected with HIV, according to the CDC. Up to a third, however, don't know it because they haven't gotten tested.

Can Quercetin Improve Athletic Performance (and Protect Against Cancer)?

A new study sheds light on one popular supplement—quercetin—which is being examined for its potential not only to improve athletic performance but also to prevent or treat a host of diseases and conditions, U.S. News's Katherine Hobson reports. The study, published this week in the International Journal of Sports Nutrition and Exercise Metabolism, looked at quercetin's effects on endurance in healthy nonathletes.

J. Mark Davis, director of the exercise biochemistry laboratory at the University of South Carolina's department of exercise science and the author of the new study, says quercetin may aid performance through its anti-inflammatory properties or because it increases the number and function of mitochondria, the energy-producing factories found in cells. It may also provide a caffeinelike boost to the central nervous system. When it comes to cancer, quercetin has shown promise in test tubes, seeming to slow the growth of cancer cells or even induce their death. But it's far too soon to stock up on supplements in the hopes of preventing the disease.

Learn how caffeine can improve athletic performance. Most studies have shown that caffeine enhances performance (by as much as 20 percent), but because the people getting caffeine in a controlled trial can probably feel it, it's possible they may be imagining the athletic boost. And here's why athletes need sleep.

Is Coffee Bad For You? In Many Cases, No

Coffee is believed to improve mood, alertness, and energy. But is it bad for you? Despite past concerns about coffee, tea, and other sources of caffeine being detrimental to health, recent research suggests that regular coffee consumption may reduce the risk of health conditions such as type 2 diabetes, Parkinson's disease, and liver cancer, U.S. News's January Payne reports. Regular coffee drinkers might even live longer. Coffee is "not only a vehicle for caffeine," says one expert. "It has a lot of other components." It's likely that those other components—such as antioxidants and fiber—account for some of coffee's health benefits, Payne writes.

Caffeine alters mood and behavior, and it can also result in physical dependence. Caffeine withdrawal typically sets in after 12 to 24 hours of abstaining from caffeinated drinks. Payne reports 6 signs of caffeine addiction that include headache, lethargy, and muscle pain. Read how drinking coffee may lower women's risk of stroke.

— Megan Johnson

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