During the winter months, when the days grow shorter, it’s not unusual to feel a little sluggish.  But if feelings of depression, irritability and exhaustion become the norm, you may have a form of depression called seasonal affective disorder (SAD).

People with SAD often experience symptoms nearly everyday as winter approaches. 

Symptoms of SAD include:

• Lack of energy.
• Feeling hopeless or worthless.
• Problems sleeping.
• Losing interest in activities you normally enjoy.
• Difficulty concentrating.
• Thoughts of death or suicide.

An online search will provide a host of things you can try to help tackle SAD, including a variety of supplements. 

“While there are some known measures you can take to help alleviate SAD, what works for one person, may not work for another,” says Erin Uhlmeyer, PharmD, Nebraska Medicine pharmacy specialist. “Oftentimes, it’s trial and error to find out what works best for you. 

If you are considering the use of supplements, here are a few things to think about first:

• Their success is largely anecdotal. Anti-depressants are the only oral medications that have been shown in studies to thwart SAD.
• Supplements are not regulated by the Food and Drug Administration, so their ingredients and effectiveness aren’t verified.
• Some supplements can interact with medications or cause other side effects, so always consult your doctor before use. 

Some of the more common supplements that have seen some success include:

• Melatonin – A hormone produced by the brain’s pineal gland that helps regulate the sleep-wake cycle and circadian rhythms. Available as a dietary supplement, many people find melatonin helpful for improving sleep disorders.
• St. John’s Wort – An herbal remedy sometimes used to treat mild depression. However, research is mixed – some studies suggest it helps, while others have shown no change at all. Discuss with your doctor first before trying it.
• Vitamin D – Not only does vitamin D keep your bones strong, it can also improve your mental health and help you sleep. As many as 1 in 4 people are low in vitamin D, according to the National Institutes of Health. Low vitamin D levels can contribute to depression, lack of sleep, fatigue and other symptoms. Ask primary care provider about checking a blood test if you think your levels may be low. 

You can increase your vitamin D levels by:

• Getting daily exposure to sunlight.
• Eating vitamin D-fortified foods (milk, orange juice, breakfast cereals and oatmeal).
• Consuming vitamin D-rich foods (salmon, tuna, mackerel, herring, sardines, eggs, beef, and liver). 

While food sources are effective, taking a vitamin D supplement may also be an option if recommended by your physician, says Dr. Uhlmeyer.

What causes SAD

Possible causes of SAD may be a combination of factors including: 

• Disrupted circadian rhythm – Reduced levels of sunlight in the fall and winter months.
• Low serotonin levels – brain chemical that affects mood and may be triggered by reduced sunlight.
• Melatonin imbalances – Melatonin helps control imbalances of the body’s melatonin levels, which affects mood and sleep patterns. 

Certain factors may increase your risk of developing SAD, including: 

• Being female.  
• Being younger.  
• Having a family history of SAD or other form of depression.  
• Having clinical depression.
• Living far from the equator. 

Other commonly recommended measures you can take to combat SAD include:

• Get adequate sleep.
• Take daily walks during daylight hours or other form of aerobic exercise. This will give you more sun exposure and increase endorphins to lift your spirits and help relieve stress and anxiety.
• Use light therapy (phototherapy), for 30 minutes in the morning. This will mimic outdoor light, and for many, may change brain chemicals that affect mood.
• Consider antidepressant medications and/or psychotherapy. Your doctor may recommend starting on an antidepressant before your symptoms begin each year. Psychotherapy or counseling can help you identify and change negative thoughts and behaviors, help you learn to manage stress and develop healthy ways to cope with SAD.
• Doing yoga, meditation, guided imagery or massage therapy.