This Week in Health: Go Swimming and Clean Your Humidifier

This week we learned that swimming is one of the best forms of exercise, since it’s easy on the joints and recruits more major muscle groups than other types of cardio. Here’s what else grabbed our attention in health this week.

The dangers of using the club drug ketamine for depression

Ketamine shows huge promise for treatment-resistant depression. But is it safe? A new study suggests that while it appears the drug can work as a rapid antidepressant, there’s not enough data yet on its long-term effectiveness and safety.

The Volkswagen scandal could shorten thousands of lives

Excess air pollution due to the Volkswagen emissions scandal could cause health problems for 1,200 people in Europe, according to a new study from MIT. The researchers say the pollution can exacerbate health issues like asthma and heart disease.

Why swimming is so good for you

Need a new exercise routine? Hit the pool. Research suggests swimming can lower blood pressure and arterial stiffness, as well as improve mood.

What everyone should know about humidifiers

Americans buy roughly 10 million humidifiers each year, but they can cause nasty infections if they’re not cleaned properly. Cleaning it every few days will do the trick.

Why you really need to exercise

A new study underlines the powerful effect of fitness on the heart. The researchers found that overweight and obese people who exercised regularly had heart disease rates similar to those of normal weight people who also exercised.

Why do I feel sleepy until the moment I crawl into bed?

Finally, an answer to one of the most irritating sleep problems. Re-training the brain takes time, but with some commitment, you can go back to getting a good night’s rest.

Liberian Ebola fighter, a TIME Person of the Year, dies in childbirth

Salome Karwah, who was among the Ebola Fighters named TIME’s Person of the Year in 2014, died recently during childbirth. Though Ebola claimed most of her family members, Karwah helped treat many people in her community, often comforting the sick by touching them when others wouldn’t dare.