Supplements That May Help Support Mood During Seasonal Changes

As daylight hours shorten and temperatures drop, many people notice changes in their mood, energy levels, and motivation. For some, these seasonal shifts are mild and manageable. For others, the darker months bring more significant challenges, sometimes referred to as seasonal affective disorder (SAD) or seasonal mood changes. Estimates suggest that SAD affects roughly 5 percent of the U.S. population, with a much larger percentage experiencing milder "winter blues."

While professional support and evidence-based approaches like light therapy are important for significant seasonal mood changes, certain supplements may help provide additional nutritional support during the darker months. Here is what the research suggests.

Understanding Seasonal Mood Changes

The reduced sunlight exposure during fall and winter months can disrupt several biological systems. Less light means less Vitamin D production in the skin, altered circadian rhythm signaling, and changes in neurotransmitter production, particularly serotonin and melatonin. These shifts can collectively influence mood, sleep patterns, appetite, and energy levels.

It is worth noting that seasonal mood changes exist on a spectrum. Some people experience only mild dips in motivation, while others face clinically significant symptoms that affect daily functioning. If your symptoms are severe or interfere with your ability to work, maintain relationships, or care for yourself, seeking guidance from a mental health professional is an important first step.

Vitamin D: The Sunshine Supplement

Vitamin D deficiency is widespread during winter months, particularly in northern latitudes where UVB radiation is insufficient for skin synthesis from roughly October through March. Research has observed associations between low Vitamin D levels and depressive symptoms, and some intervention studies suggest that supplementation may help support mood in people who are deficient.

A reasonable supplementation range for most adults during winter is 1,000 to 5,000 IU of Vitamin D3 daily, ideally taken with a meal containing fat for optimal absorption. Getting your levels tested through a simple blood draw (25-hydroxyvitamin D test) is the best way to determine your specific needs. Most practitioners consider a level of 40 to 60 ng/mL to be optimal.

Recommended products: NatureWise Vitamin D3 5,000 IU or Thorne Vitamin D/K2 Liquid

Omega-3 Fatty Acids (EPA and DHA)

Omega-3 fatty acids, particularly EPA (eicosapentaenoic acid), have been studied for their potential role in mood support. EPA appears to have anti-inflammatory properties in the brain, and some researchers theorize that neuroinflammation may contribute to depressive symptoms. Several meta-analyses have found that omega-3 supplementation, particularly formulas with higher EPA content, may provide modest mood benefits.

A typical dose used in research is 1,000 to 2,000 mg of combined EPA and DHA daily, with formulas that emphasize EPA (at least a 2:1 EPA to DHA ratio) showing the most consistent results in mood-related studies. Fish oil, krill oil, and algae-based omega-3s are all viable sources.

Recommended products: Nordic Naturals Ultimate Omega or Viva Naturals High-Potency Omega-3

Vitamin B12 and Folate

B vitamins play essential roles in neurotransmitter synthesis, including the production of serotonin and dopamine. Deficiencies in B12 and folate have been associated with depressive symptoms in observational studies. Certain populations are at higher risk for B12 deficiency, including vegetarians and vegans, older adults, and those with digestive conditions that affect nutrient absorption.

Supplementing with a B-complex that provides methylated forms (methylcobalamin for B12 and methylfolate for folate) ensures good bioavailability, particularly for people with MTHFR gene variations that may impair folate metabolism.

Recommended products: Thorne B-Complex #12 or Jarrow Formulas Methyl B-12 and Methyl Folate

Magnesium

Magnesium deficiency is common and has been associated with increased symptoms of stress, anxiety, and low mood. This mineral is involved in hundreds of enzymatic reactions, including those related to neurotransmitter function and HPA axis regulation. Some studies suggest that magnesium supplementation may help support mood, particularly in individuals with low dietary intake.

Magnesium glycinate is often recommended for its calming properties and good bioavailability without the digestive side effects that can accompany other forms like magnesium oxide. A typical dose is 200 to 400 mg of elemental magnesium daily, taken in the evening.

Recommended products: Doctor's Best High Absorption Magnesium Glycinate or NOW Foods Magnesium Glycinate

SAMe (S-Adenosyl-L-Methionine)

SAMe is a naturally occurring compound involved in methylation reactions that affect neurotransmitter metabolism, including serotonin and dopamine production. It has been studied fairly extensively for mood support, and some research suggests it may be comparable in effectiveness to certain conventional approaches for mild to moderate mood symptoms.

A typical starting dose is 400 mg daily, sometimes increased to 800 to 1,600 mg based on individual response. SAMe can be expensive and is best taken on an empty stomach. It is important to note that SAMe may interact with certain medications, particularly serotonergic drugs, so consulting with a healthcare provider before use is essential.

Recommended products: Jarrow Formulas SAMe or Doctor's Best SAMe

St. John's Wort

St. John's Wort (Hypericum perforatum) is one of the most well-researched herbal supplements for mood support, with multiple clinical trials and meta-analyses evaluating its effects. Some research suggests it may help support emotional well-being during periods of seasonal mood changes, though results have been mixed across studies.

A typical dose is 300 mg three times daily of an extract standardized to 0.3 percent hypericin. St. John's Wort has significant drug interactions, including with hormonal contraceptives, blood thinners, and antidepressants. It can also increase photosensitivity. Consulting with a healthcare provider before use is strongly recommended.

Recommended products: Nature's Way Perika St. John's Wort or Gaia Herbs St. John's Wort

Light Therapy: The Non-Supplement Foundation

While this article focuses on supplements, it would be incomplete without mentioning light therapy, which has the strongest evidence base for seasonal mood support. A 10,000-lux light therapy lamp used for 20 to 30 minutes each morning, ideally within the first hour of waking, may help regulate circadian rhythms and support serotonin production.

Light therapy is often considered a first-line approach for seasonal mood changes and can be combined with any of the supplements listed above. Look for a lamp that provides 10,000 lux at a comfortable sitting distance and filters out UV light.

Recommended products: Verilux HappyLight or Carex Day-Light Classic Plus

Putting It All Together

A reasonable approach to nutritional support during seasonal changes might include:

1. Test and optimize Vitamin D levels as the foundation
2. Add omega-3s if your dietary intake of fatty fish is low
3. Ensure adequate B12 and folate through diet or supplementation
4. Consider magnesium if you suspect deficiency or experience stress and sleep issues
5. Use a light therapy lamp every morning during the darker months
6. Explore SAMe or St. John's Wort only after consulting with a healthcare provider, particularly if you are not taking other mood-related medications

Start with one or two changes and give each supplement at least four to six weeks before evaluating its impact. Stacking too many things at once makes it difficult to identify what is actually helping.

When to Seek Professional Help

Supplements and lifestyle strategies can be valuable tools, but they are not a substitute for professional support when symptoms are significant. If you experience persistent sadness, loss of interest in activities you normally enjoy, significant changes in sleep or appetite, difficulty concentrating, or thoughts of self-harm, please reach out to a healthcare provider or mental health professional. The 988 Suicide and Crisis Lifeline (call or text 988) is available 24/7 in the United States.

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Mindfulness Guide for a comprehensive overview