One way to know how much soda people drink is to ask them. The problem? We tend to underestimate, lie or forget what we've consumed. And this is a challenge for researchers who study the links between sugar-sweetened beverages and obesity. A new study published in the Journal of Nutrition explains a technique that could help researchers get a good measurement of sugary beverage consumption — by analyzing a piece of hair or a blood sample.

As the country awaits two important Supreme Court decisions involving state laws on same-sex marriage, a small but consistent body of research suggests that laws that ban gay marriage — or approve it — can affect the mental health of gay, lesbian and bisexual Americans. When several states passed laws to prohibit same-sex marriage, for example, the mental health of gay residents seemed to suffer, while stress-related disorders dropped in at least one state after gay marriage was legalized.

People smell yummy to mosquitoes. So yummy, in fact, that our scent is a big way the pesky insects track us down. But just how much mosquitoes like Eau de Human may not be entirely up to the bugs.

Mosquitoes are more attracted to human odors when they're infected with the malaria parasite, scientists reported Wednesday in the journal PLOS ONE.

Scientists say they have, for the first time, cloned human embryos capable of producing embryonic stem cells.

The accomplishment is a long-sought step toward harnessing the potential power of embryonic stem cells to treat many human diseases. But the work also raises a host of ethical concerns.