Seasonal Affective Disorder (SAD), also known as the winter blues or seasonal depression, is a type of depression related to the change in seasons.

When Does It Happen? SAD is most common in the fall and winter months when the days are shorter and there is less exposure to sunlight.

Why Does It Happen? Sunlight plays an essential role in the body’s natural production of vitamin D, serotonin, and melatonin. Vitamin D contributes to serotonin production. Serotonin, which regulates mood and appetite, converts to melatonin. Melatonin controls sleep and wake cycles. When there is less exposure to natural light in the winter months, the body may produce insufficient levels of these chemicals, leading to depression, sleep disruption, or other changes in the body.

What Are the Symptoms?  The signs of SAD range from mild to severe. Those who suffer from seasonal affective disorder may:

• feel tired or fatigued
• lack the ability to concentrate or cope with stress
• feel sad, down, or irritable
• withdraw from social activities
• crave carbohydrates or sugary foods
• notice weight gain or loss

WFP’s Take-Home Advice

1. Start early: optimize sunlight intake in the summer and early fall months. Maintain adequate levels of vitamin D by taking a vitamin D3 supplement. Most adults need to supplement with 5,000–10,000 IUs during the fall and winter months due to the seasonal decrease in UVB-rays. For a high-quality formula, see our WFP Vitamin D3 with K2. Before starting a supplement, consult with your medical provider on your vitamin D levels and appropriate dosage.
2. Increase your exposure to natural light as often as possible. During the day, keep blinds and curtains open and turn indoor lights off, when possible, to maximize natural sunlight exposure. Take a walk outside in the morning or midday. Anytime that you can get outdoors in the sunlight will help boost your vitamin D intake the natural way. Learn more about our WFP approach to sunlight and vitamin D by reading our article: 11 Tips for Sunlight, Sunscreen, & Vitamin D.
3. Aim to exercise at least 3–4 times a week for 30 minutes. Consistent, moderate exercise has been shown to help alleviate depressive symptoms associated with seasonal affective disorder. When sunlight is available, try to exercise outdoors to maximize exposure to natural light.
4. Certain regions of the nation experience less sunlight during fall and winter months. When sunlight is limited, you can use a dawn simulator—a form of light therapy that functions as a natural wake-up light in the bedroom. Dawn simulators, which mimic the light changes of a natural sunrise, are shown to be effective in the treatment of seasonal affective disorder. The gradual increase in brightness occurs over a set period of time in the morning and is intended to help the body regulate sleep and wake cycles.
5. Supplement with high-quality, animal-based omega-3 fats, such as our WFP Fish Oil Complete.
6. Decrease or eliminate sugar and grains. Consume whole foods that have not been processed and still retain their natural nutrients.
7. Keep a regular sleep schedule of 7–9 hours a night. For other ways to ensure a good night’s rest and to optimize sleep the natural way, read our recommendations: 12 Tips for Better Sleep.
8. Make time to connect and talk with a friend, loved one, or a counselor/therapist if depression symptoms are severe.
9. Use meditation as a way to support and strengthen your mind and body. Try the guided meditation app Waking Up, which offers insight and guidance for staying balanced and relaxed while also exploring our connection to the world around us. The Calm and Headspace smartphone apps are also great tools that help increase relaxation and mindfulness through meditation. In addition to boosting emotional and mental well-being, both apps also provide guided meditation for sleep. To learn more about the benefits of meditation and how this practice can help you positively influence your mind in order to control your health, read our article Meditation: The Mind & Body Benefits.
10. In addition to sunlight, exercise, and supplementing with vitamin D and fish oil, there are many other natural strategies you can implement to boost your immune system during the winter months as well as all year round. Read our tips for strengthening your immune system here.

To see all of our Wiseman Health supplements, visit our Online Store; to explore other ways to optimize your health the natural way, see our Preventive 10 strategies.

Editor’s Note: This article was originally published on October 20, 2015 and has since been updated. 

Sources and References:

Danilenko KV, Ivanova IA. (2015, June 15) Dawn simulation vs. bright light in seasonal affective disorder: Treatment effects and subjective preference. Retrieved October 23, 2017 from https://www.ncbi.nlm.nih.gov/pubmed/25885065

Groom KN, O’Connor ME. (1996 October) Relation of light and exercise to seasonal depressive symptoms: preliminary development of a scale. Retrieved October 23, 2017 from https://www.ncbi.nlm.nih.gov/pubmed/8902007

Adams, C. (2013, January 01) One Hour of Light Therapy Reduces Depression. Greenmedinfo.com.

Vitamin D Council What Is Vitamin D? vitamindcouncil.org.