Allison Aubrey

The U.S. Preventive Services Task Force has a new recommendation aimed at preventing HIV infections and AIDS. The influential panel's guidance says people at high risk of being infected with HIV should be offered preventive antiretroviral medications — taken in a daily pill.

There's lots of evidence that preexposure prophylaxis — also known as PrEP — is effective. The Food and Drug Administration-approved pill Truvada contains two antiretroviral medicines (tenofovir and emtricitabine).

For roughly 40 million Americans, SNAP benefits are a lifeline.

The Supplemental Nutrition Assistance Program, formerly known as food stamps, delivers about $60 billion in aid each year. And retailers that accept SNAP benefits are required to stock a variety of staple foods — including a minimum number of fruits and vegetables, meat, dairy and grain options.

The Food and Drug Administration is holding its first public hearing on CBD, the cannabis extract that has quickly grown into a billion-dollar industry. Today's hearing will help officials determine how to regulate CBD products.

The compound can be extracted from marijuana or from hemp. It's promoted as a way to ease anxiety and inflammation – and it doesn't get people high because it doesn't contain THC, the psychoactive component of the cannabis plant.

There's nothing magical about the number 10,000.

In fact, the idea of walking at least 10,000 steps a day for health goes back decades to a marketing campaign launched in Japan to promote a pedometer. And, in subsequent years, it was adopted in the U.S. as a goal to promote good health. It's often the default setting on fitness trackers, but what's it really based on?

"The original basis of the number was not scientifically determined," says researcher I-Min Lee of Brigham and Women's Hospital.

The Food and Drug Administration sent a letter to the food industry on Thursday, urging companies to get behind the initiative to standardize the use of the phrase "best if used by" on packaged food labels.