It’s Blue Monday, the saddest day of the year

The relatives have all gone home, the decorations are put away for another year, and the only thing left over from the holidays is, well, the leftovers. But that sigh you let out when the clock ticked over into 2015 was probably not one of relief.

Across the pond, the first Monday of the new year is known as Blue Monday – U.K. scientists have analyzed social media and found that there is a dramatic increase in postings related to guilt, melancholy and sadness on this day.

We asked Dr. Harold Koenigsberg, professor of psychiatry at Mount Sinai Hospital in Manhattan and a member of the Hope for Depression Research Foundation, about how to keep our spirits bright through the long winter nights.

1. Reset your body clock

The role of light is not just about getting enough vitamin D; your body clock is reset every day by the sunrise. “But when the sunrise comes later, as it does in winter, then that biological clock gets shifted in time,” explains Koenigsberg. So instead of waiting for the sun to come up, start the day early by sitting next to a bright light an hour before sunrise. This is also a good time to start that resolution about exercise – “if you can combine the two, that’s best,” he says. And stop drinking caffeine completely after 2 p.m. to ensure you won’t have trouble falling asleep.

2. Get out of your own head

Sometimes, the best way to gain perspective on your own life is to help others – the feeling of altruism and social interactions are both helpful to lifting your funk. But it doesn’t have to be volunteering; rekindle your interests or find like minds through Meetup.com who share a new passion.

3. Forgive yourself

If you racked up debt over Christmas, don’t ignore the bills piling up in your mailbox. Accept what’s done and look for a solution.

4. Take mental breaks

Don’t be ashamed of taking a few minutes out of your day to watch a silly cat video on YouTube. “When people get into a rut, feeling bad, it can help to have things that distract them from those thoughts,” Koenigsberg says. Or, even better, use that break to take a lap around the office or walk up a couple flights of stairs – research has shown that about 5 minutes of movement for every hour of sitting can counter its negative health effects.