Seasonal Affective Disorder, commonly referred to as SAD, is a type of depression that comes and goes with the seasons, typically starting in the late fall and early winter and going away during the spring and summer. With the arrival of daylight’s savings this month, many people may feel their moods change along with the time — in fact 10–20 percent of Americans report feeling tired or sad when there are fewer hours of daylight in the winter months.

What causes this wintertime melancholy attitude? Research has shown that it’s a biochemical imbalance that’s at play. When winter rolls around, people with SAD experience a significant dip in serotonin, the neurotransmitter responsible for mood, appetite, sleep, memory and libido.

Even if you don’t suffer from full-blown seasonal depression, you may feel more stressed and pessimistic come winter and the holidays. Luckily, there are easy ways to boost your mood when you start feeling down. Here are some strategies to keep up your energy this time of year.

Make sure to get some Vitamin D

The blues hit worst in the mornings, so make sure to get your daily dose of vitamin D (which comes from the sun) at this time of day. Open your blinds, go out on a stroll and enjoy the natural light.

Work out

When you work out, the body naturally release endorphins, which will make you feel happier and sometimes even euphoric. Research suggests that exercise might be comparable to therapy or anti-depressants as an effective treatment for depression.

Keep up your routine

Although winter may make you want to hibernate, don’t neglect your favorite hobbies. Maintain your typical social calendar and stay physically active to boost your mood.

Stay away from sugar

Research shows that sugar not only affects your physical health but your mental health as well. People that consume the most sugar have higher rates of depression, and researchers theorize that it hinders the body’s ability to cope with stress.

Relax and meditate

Studies show that exercise and meditation can alleviate the symptoms of stress and anxiety. Yoga is an excellent exercise to ease tense muscles while simultaneously practicing mindfulness.