Fighting to keep your eyes open? Here's why

By Esther Crain
October 16, 2014

You've heard of the winter blues-that plunge in energy level and mood that sets in when the weather gets cold. Welcome to the autumn version of it. As the days get shorter and you're exposed to a decreasing amount of sunlight, your body reacts by pumping out more melatonin, a hormone that helps you doze off, and putting the brakes on serotonin production, causing fatigue, says Holly Phillips, M.D., a women's health specialist in New York City.

Early in fall, the energy suck is not always so noticeable-it's not quite heavy sweater season, and the sun still brightens your commute home. But once daylight savings time ends, more of our waking ours are spent in the dark, and fatigue kicks in, says Phillips. "Less exposure to light also disrupts sleep and wake cycles, and that can make your sleep more restless-another reason you feel tired during the day," she says. Dark, chilly days also make you want to hibernate, not hit the gym. The less physical activity you get, the more lethargic you feel.

The trick to feeling more fueled is to do things that boost serotonin and postpone melatonin production. "Head outside in the afternoon, even for a few minutes at a time, to get extra sunlight exposure," suggests Phillips. "Try to get to the gym too." Brilliant idea: Give yourself a double energy surge by taking your workout outdoors as often as possible. Loading up on vitamin D-rich foods (think salmon, milk, eggs, and fortified cereal) can also make a difference. "The less sunlight you get, the more your vitamin D levels sink, and that can exacerbate exhaustion," says Phillips.