Immune Function
| Supplement | Amount | Why |
|---|---|---|
Andrographis | 48 to 60 mg andrographolides in two to three divided doses daily |  [3 stars] Andrographis, with its immune system–enhancing actions, has been shown to reduce the severity of the common cold and may prevent the onset of a cold in healthy people. |
Multivitamin | Follow label directions | [3 stars] Taking a daily multivitamin can help prevent deficiencies that make you a target for infections. |
Vitamin E | 200 IU daily | [3 stars] Vitamin E enhances some measures of immune-cell activity in the elderly. |
Ashwagandha | 3 to 6 grams daily of the dried root as tea or in a capsule |  [2 stars] Ashwagandha stimulates the immune system and is considered a tonic or adaptogen—an herb with multiple actions that counteract the effects of stress and generally promote wellness. |
Asian Ginseng | 100 mg of a standardized extract twice per day | [2 stars] Asian ginseng has a long history of use in traditional herbal medicine for preventing and treating conditions related to the immune system. |
Beta-Carotene | 25,000 to 100,000 IU per day for nonsmokers only | [2 stars] Beta-carotene has been shown to increase immune cell numbers and activity. It has also been shown to enhance cancer-fighting immune functions in healthy people. |
Echinacea | 3 to 5 ml of liquid extract three times per day | [2 stars] Studies have found that echinacea stimulates the function of a variety of immune cells, particularly natural killer cells. Taking it appears to speed recovery from the common cold. |
Eleuthero | 10 ml of tincture three times per day | [2 stars] Eleuthero has historically been used to support the immune system. |
Glutamine (Post-Exercise Infection) | Refer to label instructions | [2 stars] A study giving athletes glutamine, an amino acid important for immune system function, reported significantly fewer infections with glutamine. |
Probiotics | 10 billion colony-forming units a day of acidophilus or bifidobacteria-only for intestinal infections | [2 stars] Probiotics help stimulate the intestine’s immune system and slow the growth of infectious organisms. |
Selenium | 100 mcg daily with 20 mg zinc daily | [2 stars] Selenium supplements have been reported to help improve immune function in seniors.
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Thymus Extracts | 1 to 1.5 mg thymus polypeptides per 2.2 lbs body weight | [2 stars] The thymus gland is responsible for many immune system functions. A thymus extract known as Thymomodulin has been shown to improve immune function in some people. |
Vitamin A | Consult a qualified healthcare practitioner | [2 stars] Vitamin A plays an important role in immune system function and helps mucous membranes, including those in the lungs, resist invasion by microorganisms. |
Vitamin C | Consult a qualified healthcare practitioner | [2 stars] Vitamin C stimulates the immune system. While taking it has only a small effect in preventing colds, it does significantly reduce the duration of a cold when taken at the onset. |
Astragalus | Refer to label instructions |  [1 star] Complex polysaccharides in astragalus affect the immune system. One study showed that astragalus elevate antibody levels in healthy people. |
Beta-Glucan | Refer to label instructions | [1 star] Beta-glucan activates white blood cells, which in turn can recognize and kill tumor cells, correct oxidative damage, and speed up recovery of damaged tissue. |
Cat’s Claw | Refer to label instructions | [1 star] Substances found in cat’s claw, called oxyindole alkaloids, have been shown to stimulate the immune system. |
Cordyceps | Refer to label instructions | [1 star] Cordyceps has immune-strengthening actions and may be helpful in a wide range of conditions in which the immune system is weakened. |
DHEA | Refer to label instructions | [1 star] Supplementing with the hormone DHEA may improve immune functioning. |
Fo-Ti | Refer to label instructions | [1 star] Preliminary research suggests that fo-ti plays a role in a strong immune system and has antibacterial action. |
Green Tea | Refer to label instructions | [1 star] Green tea has stimulated production of immune cells and has shown anti-bacterial properties in some studies. |
Ligustrum | Refer to label instructions | [1 star] Ligustrum appears to stimulate the immune system and is often combined with astragalus in traditional Chinese medicine. |
Lycopene | Refer to label instructions | [1 star] Large amounts of the carotenoid lycopene have been shown to increase the activity of natural killer cells in the elderly. |
Maitake | Refer to label instructions | [1 star] Complex polysaccharides present in maitake appear to increase immune function. |
Noni | Refer to label instructions | [1 star] Studies show noni to have some immune-enhancing activity. |
Vitamin B12 | Refer to label instructions | [1 star] A deficiency of vitamin B12 has been associated with decreased immune function. Restoring vitamin B12 levels may improve levels of immune cells. |
Whey Protein | Refer to label instructions | [1 star] Whey protein appears to improve some aspects of immune function. One trial showed that whey protein increased blood glutathione levels in a group of HIV-infected people. |
Zinc | 25 mg daily | [1 star] Zinc supplements have been reported to increase immune function. Some doctors recommend zinc supplements for people with recurrent infections. |
- 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.
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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.