During the winter months, you may wake up when it’s dark. And you’re probably still at work when it’s dark outside again — not all that many hours later. Is it any wonder that we have a harder time sticking to weight loss goals and tend to soothe our low-energy selves with food to help get us through the season?
Having fewer hours of daylight affects pretty much all humans to some extent, but some of us are hit harder than others. People who are most impacted by the cold and gloom may suffer from seasonal affective disorder, which is also (and aptly) known as SAD. But even if you aren’t clinically depressed this time of year, the dreary weather conditions can still have a negative impact on your mood, energy levels, and the types of snacks you’re reaching for.
Here’s what you need to know about the winter blues, whether they’re mild or severe; how they impact your appetite; and what you can do to curb those unhealthy seasonal food cravings.
What Is Seasonal Affective Disorder?
SAD is a form of depression that typically happens during the fall and winter months when the sun is shining fewer hours a day. According to the American Psychiatric Association, about 5 percent of adults in the U.S. experience SAD, and it can last for as much as 40 percent of the year, depending on where you live. Some people do experience SAD in the spring and summer rather than the winter, though it’s not as common.
The reasons for wintertime SAD are multifaceted and not fully understood. One hypothesis has become popular: “When the days are short and there’s no sunlight, our serotonin levels decrease,” says Ani Kalayjian, PhD, a professor of psychology at Columbia University in New York City and founder of MeaningfulWorld. While serotonin has been recently debated in a meta-analysis published in Molecular Psychiatry in July 2022, it has often been said to be a brain chemical that plays a key role in our mood — and our appetite.
Many people experience mild seasonality to their moods, generally feeling better in the spring and summer months, “but we only consider folks to have SAD if their mood in the darker months reaches the threshold of a full depressive episode,” says Danielle Keenan-Miller, PhD, a clinical psychologist in Los Angeles.
How SAD May Affect Your Appetite
Just as research indicates that a lack of sunlight may correspond with a decrease in serotonin levels, your carb cravings may also be more intense at this time of year. Why? Carbohydrates can increase serotonin, as shown in a historical study published in Obesity in November 1995. So it may be unsurprising that in the colder months, many people turn to comfort foods that are often carbohydrate-rich, as Teralyn Sell, PhD, a holistic mental health therapist and brain health coach in Menasha, Wisconsin, points out.
While a study published in March 1997 in Comprehensive Psychiatry reports that people with SAD selectively eat more carbohydrates — particularly sweets but also starchy foods like bread, pasta, rice, and potatoes — trends in carb intake also appear in those who may not have SAD. On Lose It!, users show a slight increase of roughly 1 to 3 percent in their carbohydrate intake between summer and fall, with the largest increases in the colder regions of the Midwest and Northeast.
SAD can affect your appetite in other ways, too. According to a study published in Frontiers of Psychology in August 2020, people with SAD tend to consume significantly larger dinners and more evening snacks, and report a higher frequency of emotional eating. “There are also higher levels of some disordered eating behaviors including binge eating among individuals with SAD,” says Keenan-Miller.
These appetite effects can be even more significant than in people who suffer from major depressive disorder. People struggling with SAD are more likely to experience increased appetite and weight gain, the Mayo Clinic reports, than those who have depression without a seasonal variation. But if you do have a SAD diagnosis, taking care of your mental health should be your priority over weight loss.
What Are the Symptoms of SAD?
In addition to an increase in appetite and more intense carb cravings than you experience at other times of the year, the National Institute of Mental Health says that other symptoms of SAD can include:
- Changes in sleep or appetite, or unplanned weight changes
- Persistent sad, anxious, or “empty” mood most of the day for at least two weeks
- Feelings of hopelessness, frustration, irritability, or pessimism
- Loss of interest or pleasure in hobbies and activities
- Decreased energy
- Difficulty concentrating or making decisions
- Physical aches or pains or digestive problems
- Thoughts of death or suicide attempts
7 Tips and Tricks to Keep Your Diet on Track
If the description of SAD has your name written all over it — with or without a formal diagnosis — or you just find yourself with less pep in your step during the winter, our experts offer these ideas to help you stay on track.
1. Check Your Vitamin D Levels
Vitamin D is an essential nutrient for all of your neurotransmitters, including serotonin. Higher levels of serotonin can help keep your appetite on track. There is also some research to suggest vitamin D may support weight loss, though more studies on this are needed.
Your doctor can order a simple blood test to check your vitamin D levels. “Getting a baseline marker for vitamin D is very important for your overall mood,” says Sell. According to Mount Sinai, experts typically consider a vitamin D level between 20 and 50 ng/mL to be within normal range.
It’s very difficult to get enough vitamin D from your diet because it doesn’t naturally occur in many foods, so it’s no surprise many of us fall short of the recommended amounts of vitamin D. According to the National Institutes of Health (NIH) Office of Dietary Supplements, as many as 92 percent of men and 97 percent of women don’t get enough from their diet. If this is you, make a point of getting outside when the sun is overhead. You may also wish to talk to your doctor about supplementation, advises Sell. Since vitamin D can interact with certain medications, reports the NIH, it’s best to work with your healthcare provider rather than supplement on your own.
2. Increase Your Natural Light Exposure
Make your indoor environment as bright as possible while the sun is overhead. Open your curtains and blinds to let natural light in. “Arrange your environment to maximize exposure to sunlight,” says Sell. So if your home office is in a windowless basement, see if you can find desk space where the rays of the sun will find you. Sunlight is a powerful mood booster, experts say.
However, tests show that windows and car windshields block most UVB rays, so sitting by a window, though certainly beneficial to your mental health and wake/sleep rhythms, will not trigger your body to make vitamin D. For that, you’ll need to be outdoors.
3. Try Light Therapy
Exposure to bright light, particularly in the morning, can help regulate the body’s internal clock and improve mood. For the days (or weeks) that the sun isn’t streaming through the gloomy winter cloud cover, light therapy boxes are designed to simulate natural sunlight and are often recommended for individuals with SAD, says Sell. Sometimes, these are called SAD lamps. A study of 50 people in Sweden with SAD or sub-clinical SAD (S-SAD) found that using light therapy boxes did help reduce depression in both groups, reported an article published in June 2008 in the Journal of Affective Disorders.
And it’s never too soon to talk to your doctor about whether a SAD lamp is right for you. “Some evidence suggests that starting lightbox treatment prior to the time of year that the depression usually starts may even prevent the onset of depressive symptoms,” Keenan-Miller explains.
4. Make a Commitment to Exercise
Moving around more is a two-fer for keeping your weight on track: It helps burn some of the extra calories you may be eating, and research has found exercise also helps lift your mood. If your low serotonin levels have you stuck in bed, “find a workout partner or mentor to help you commit to exercise,” says Kalayjian. She also recommends yoga, tai chi, or other types of movement that involve breathwork, wellness practices that can positively impact your energy and your mental health. As long as you’re prepared for the cold, engaging in outdoor exercise has multiple benefits, including boosting your mood and your vitamin D.
5. Engage in Meaningful Activities
Keeping our brains engaged and our hands busy can help distract us from eating too much or the wrong things. A new hobby can help give you the mindset shift that you may desperately need this time of year. Kalayjian suggests starting a photo album project that you can share with your friends or family, or taking up a knitting project. Or if you’re feeling particularly stressed, try coloring mandalas. It’s meditative, which is probably why one historic study published in Art Therapy in 2005 showed the activity can reduce anxiety.
6. Consider Medications or Therapy
If the light boxes and sunny windows aren’t doing the trick, Keenan-Miller says antidepressant medications can be taken to help ease your symptoms. If you are diagnosed with SAD and you and your healthcare provider agree antidepressant medications may be of help, your provider may prescribe that you take them temporarily, in the fall through the spring, research shows. A form of talk therapy called cognitive behavioral therapy may also be helpful.
7. Make Your Winter Comfort Foods More Healthy
Better nutritional habits can definitely have an impact on your mood. Seek out the foods that naturally contain vitamin D, such as fatty fish (like trout, salmon, tuna, and mackerel), fortified dairy, and mushrooms. And a pot of vegetable soup that uses fewer starchy ingredients like potatoes, corn, beans, and squash can give you the warmth you crave without all the carbs.
Editorial Sources and Fact-Checking
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- Fahad Almutawa F, Vandal R, Wang SQ, et al. Current Status of Photoprotection by Window Glass, Automobile Glass, Window Films, and Sunglasses. Photodermatology, Photoimmunology & Photomedicine. March 5, 2013.
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If you or a loved one is experiencing significant distress or having thoughts about suicide and need support, call or text 988 to reach the 988 Suicide & Crisis Lifeline, available 24-7. If you need immediate help, call 911.