| By Barbara Wexler, MPH |
Seasonal affective disorder (SAD) is a mood disorder, a type of depression that usually occurs during specific seasons, most often beginning in late fall or winter as the days get shorter and there’s less daylight. It sometimes coincides with the time change from daylight saving time to standard time, and often ends in the spring as the days lengthen.
The shorter days of fall and winter and less sunlight exposure can disrupt our circadian rhythms (the body’s internal clock) and lower levels of serotonin, a chemical in the brain that affects mood. Melatonin, a hormone that regulates sleep, also may increase, leading to feelings of fatigue. Although anyone can experience SAD, it’s more common in people living far from the equator where days are shorter and winters are longer.
SAD can make it hard for people to stay engaged and motivated during the winter. People with SAD may find everyday activities challenging, such as going to work or school, socializing, and keeping up with responsibilities. It can also affect relationships, job performance, and overall well-being. Many people experience cravings for carbohydrate-rich foods, gain weight, and feel sluggish, adding to the difficulty of coping with winter.
To diagnose SAD, doctors look for seasonal patterns in symptoms across multiple years. Key diagnostic criteria include experiencing symptoms that align with the changing seasons, typically for at least two years in a row.
Roughly 11 million people in the U.S. suffer from SAD and an additional 25 million have a milder condition known as “winter blues.” SAD symptoms like low energy, sadness, sleep problems, and difficulty concentrating can disrupt daily life and make simple activities feel exhausting. Fortunately, there are ways to prevent and treat SAD, which can make a big difference for those affected.
Prevention Strategies
Though we can’t control the seasons, there are several proactive steps people can take to manage or even prevent SAD symptoms before they fully take hold:
- Light Exposure: Make the most of daylight by going outside every day, even if it’s cloudy. Natural light, even in small doses, can help maintain mood stability. Open blinds and sit close to windows, especially in the morning, to boost natural light intake.
- Start Light Therapy Early: Some people start light therapy in early autumn to “get ahead” of the seasonal slump. Using a lightbox that emits bright UV-filtered light (typically around 10,000 lux) for 20–30 minutes each morning can stimulate serotonin production and help regulate circadian rhythms.
- Physical Activity: Regular exercise, particularly outdoors, is one of the most effective ways to lift mood and energy levels. Exercise increases endorphins (“feel-good” hormones produced in the brain) that naturally combat depression. Activities like brisk walking, jogging, or cycling are great options.
- Mindful Sleep Patterns: Consistent sleep helps keep the body’s internal clock steady, which is especially beneficial for people with SAD. Aim for 7–9 hours of sleep and avoid staying up too late. Try dimming lights an hour before bed and limiting blue-light exposure from screens.
- Diet Adjustments: Since cravings for carbs and sugary foods are common with SAD, balancing meals with protein, fiber, and whole grains can prevent energy crashes. Omega-3 fatty acids found in fatty fish, flaxseed, and walnuts may also help regulate mood.
- Social Engagement: Staying socially active helps fend off isolation and loneliness, which can exacerbate SAD symptoms. Scheduling regular visits with friends, joining a winter hobby group, or volunteering can provide valuable mood-boosting interaction.
Treatments
For those who experience symptoms despite preventive steps, several treatment methods are effective at easing SAD symptoms.
- Light Therapy (Phototherapy): Light therapy, one of the most common treatments, involves daily use of a lightbox. Experts suggest starting with 10–15 minutes and gradually increasing to about 30 minutes each morning. Consistency is key—many people find that light therapy helps to boost their mood after just a week or two.
- Cognitive-Behavioral Therapy (CBT): This type of “talk therapy” is helpful for developing coping strategies and reframing negative thoughts. Specifically, CBT tailored for SAD (CBT-SAD) focuses on reframing thoughts about wintertime activities and establishing pleasurable winter habits. Regular sessions can support people struggling with SAD, helping them develop tools for the long term.
- Medication: Antidepressants such as selective serotonin reuptake inhibitors (SSRIs) like fluoxetine and sertraline can help balance serotonin levels. Some people take these seasonally, starting in the fall and tapering off in spring under medical guidance.
- Vitamin D Supplements: Although the research on vitamin D’s effect on SAD is ongoing, vitamin D deficiency is linked to depression. Since in the winter many people get less vitamin D from sunlight, it may be worth discussing a vitamin D supplement with a healthcare provider.
- Mindfulness Practices: Techniques like meditation, yoga, deep breathing, and journaling can increase self-awareness and help to manage stress. Setting aside a few minutes daily for mindfulness can help relieve worries and improve mental resilience.
- Complementary and Alternative Therapies: Some people get symptom relief from practices like acupuncture, massage therapy, or aromatherapy. While these aren’t cures, they may help some people reduce stress and contribute to overall well-being, especially when combined with other treatments.
SAD can feel overwhelming, but with a combination of preventive measures and treatments, it’s manageable. For people dealing with this type of depression, being kind to themselves, taking preventive measures, and reaching out for help when needed can go a long way toward improving how they feel.
For more information on this topic, please see the “Seasonal affective disorder (SAD)” portal in the Gale Health and Wellness database:
