(WTVO) — The winter blues affect many of us. The cold, dark days just seem to put a damper on moods. For some, the effects are more severe and can cause seasonal affective disorder (SAD).

Just like many are stricken with the winter blues, or SAD, many try and claim vitamin D supplements can help partially alleviate symptoms. Vitamin D levels tend to be lower when people have less exposure to sunlight and clinical studies have found that vitamin D levels are lower in depressed individuals, according to Centura Health.

But that doesn’t mean vitamin supplementation necessarily works. Is there any evidence that taking vitamin D can improve seasonal sadness?

The evidence is mixed, according to HealthMatch. While one study found supplementation with 5,000 IU (international units) of vitamin D per day during winter significantly reduced symptoms of SAD in women, another study did not find any evidence of alleviating symptoms.

The U.S. Department of Health and Human Services is also ambivalent on vitamin D’s ability to treat SAD, saying “it’s unclear whether vitamin D supplementation can help to relieve SAD symptoms.”

Some research shows vitamin D can help in mild cases of seasonal depression, however studies have also shown it to be ineffective in moderate and severe cases.

Another, potentially more effective, option for treating SAD is light therapy, which has been used as a primary treatment for SAD since the 1980’s, according to the National Institute of Mental Health.

The therapy consists of sitting in front of a specialized bright light box for 30-45 minutes.

“For both seasonal and nonseasonal depression, the effectiveness of light therapy is approximately the same as antidepressant medications, or popular forms of psychotherapy such as cognitive behavioral therapy,” said Dr. Richard S. Schwartz, associate professor of psychiatry at Harvard Medical School. 

Regardless of what treatment is used, talking to a doctor about seasonal symptoms is highly recommended.