Allison Aubrey

Well, it's official. Beginning today, all restaurant chains in the U.S. with 20 or more locations must post calories on menus or menu boards.

When Congress passed the Affordable Care Act, back in 2010, the federal calorie posting mandate was born.

Many chains, including McDonald's, Panera and Starbucks, began posting calories several years back. But the proposed regulations hit several snags as industry groups lobbied for changes. Now, there's no escaping them.

Lyme disease was once unheard of in western Pennsylvania, where Barbara Thorne, now an entomologist at the University of Maryland, spent time as a kid.

Thorne knew that if black-legged ticks are infected with bacteria called Borrelia burgdorferi, they can transmit Lyme to people and, that if untreated, symptoms can range from fever, fatigue and a rash, to serious damage to the joints, heart and nervous system.

When Melisa Martinez's son, Juelz, was born very prematurely at 25 weeks back in January, doctors at University of California, Davis Children's Hospital gave him probiotics. "They told me the probiotics may help reduce the risk of infection," Martinez says. Now, Juelz is home and doing well.

As more states legalize marijuana, there's growing interest in a cannabis extract — cannabidiol, also known as CBD.

It's marketed as a compound that can help relieve anxiety — and, perhaps, help ease aches and pains, too.

Part of the appeal, at least for people who don't want to get high, is that CBD doesn't have the same mind-altering effects as marijuana, since it does not contain THC, the psychoactive component of the plant.

Falls are a leading cause of injury and death among older adults. In 2014, about 1 in 3 adults aged 65 and older reported falling, and falls were linked to 33,000 deaths.

If you want to reduce the risk of falling, regular exercise may be your best bet, according to the latest recommendations from the U.S. Preventive Services Task Force.

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