Penn Herb Wellness Guide
Seasonal Affective Disorder
- Reliable and relatively consistent scientific data showing a substantial health benefit.
- Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
- For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.
Our proprietary “Star-Rating” system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by some in the medical community, and whether studies have found them to be effective for other people.
For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.
| Supplement | Amount | Why |
|---|---|---|
L-Tryptophan | With doctor's supervision, 2 to 4 grams per day, increasing up to 6 grams if no improvement |  [2 stars] Some research suggests that L-tryptophan alone or in combination with light therapy may improve SAD symptoms.
|
St. John’s Wort | Consult a qualified healthcare practitioner | [2 stars] St. John’s wort, an herb well known for its antidepressant activity, may improve SAD symptoms. |
Vitamin D | Refer to label instructions | [2 stars] Supplementing with vitamin D may improve SAD in people with low levels of the vitamin. |
5-HTP | 900 mg a day of a standardized extract |  [1 star] The supplement 5-Hydroxytryptophan increases serotonin production and has shown antidepressant activity. It may be useful in the treatment of SAD. |
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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.