One day inside probably won’t hugely affect your health—but it’s not great to constantly stay cooped up from morning until dark. The biggest issue is that entering hibernation mode means you don’t get any exposure to natural light. Sunlight tends to improve your mood, and it helps your body produce vitamin D, which has been shown to help regulate the immune system, reduce inflammation in the body, and more. Sunlight also helps keep your internal body clock on schedule; your circadian rhythm plays a major part in regulating your appetite, sleep schedule, and energy levels. Research has shown that excessive exposure to electric lighting can throw off those internal rhythms.
Let’s not forget the slew of health benefits that spending time in nature provides: Getting some green can help alleviate symptoms of depression, up your energy, and improve your overall well-being. Also, a study out of University of Glasgow in Scotland found that people who walked, ran, or biked in nature had a lower risk of poor mental health than people who exercised at the gym or at home.
I understand that on certain days it can feel impossible to spend substantial time outdoors. Just don’t make cocooning a habit. And keep in mind that carving out even 20 minutes per day of “ecotherapy,” as some call it, can do your mind and body good.
Health's medical editor, Roshini Rajapaksa, MD, is assistant professor of medicine at the NYU School of Medicine.
This article originally appeared on Health.com.