Penn Herb Wellness Guide
Influenza
- 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 |
|---|---|---|
Echinacea | 3 to 5 ml of liquid formulas or 300 mg of powdered root supplements three times per day |  [2 stars] Taking echinacea may help clear flu symptoms faster. |
Elderberry | Adults: 4 Tbsp daily of a syrup containing 38% elderberry extract; children: half a dose (2 Tbsp) | [2 stars] Supplementing with elderberry may help speed recovery. |
Garlic | 2.6 grams per day | [2 stars] Healthy volunteers who supplemented with an aged-garlic extract for 90 days decreased the number of days on which severe cold or influenza symptoms occurred by 58%. |
Green Tea Catechins | Gargle with a liquid extract containing 200 mcg per ml three times per day | [2 stars] In one study, elderly nursing home residents in Japan who gargled with a green tea extract were less likely to get the flu than those who gargled without the green tea extract. |
Vitamin C | 100 mg daily | [2 stars] Supplementing with vitamin C may reduce your flu risk. |
Vitamin D | 800 IU per day for two years; then 2,000 IU per day after that | [2 stars] In one study, long-term vitamin D supplementation for three years significantlyreducedflu and coldsymptoms.
|
Asian Ginseng | Refer to label instructions |  [1 star] Asian ginseng has immune-enhancing properties, which may play a role in preventing infection with the influenza virus. |
Boneset | Refer to label instructions | [1 star] Boneset has been shown in studies to stimulate immune-cell function, which may explain its traditional use to help fight off minor viral infections, such as the flu. |
Eleuthero | Refer to label instructions | [1 star] Eleuthero has immune-enhancing properties, which may play a role in preventing infection with the influenza virus. |
Goldenseal | Refer to label instructions | [1 star] Goldenseal used in combination with wild indigo has been reported to have immune-enhancing effects. |
Meadowsweet | Refer to label instructions | [1 star] The salicylates in meadowsweet give it a mild anti-inflammatory effect and the potential to reduce fevers during a cold or flu. |
Thuja | Refer to label instructions | [1 star] Thuja used in combination with wild indigo has been reported to have immune-enhancing effects. |
Wild Indigo | Refer to label instructions | [1 star] Wild indigo contains polysaccharides and proteins that have been reported to stimulate the immune system. It is often used in combination with herbs such as echinacea, goldenseal, or thuja. |
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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.