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CL Answers (39)

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Clinical Updates (21)

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Prebiotics for Immune Health

Prebiotics are complex sugars which can support the growth of probiotic organisms in the gut. A recent study reported a specific type of prebiotic increased amounts of beneficial bacteria and improved certain markers of immune function in older men and women. Get the details, including dosage, plus our tests of popular probiotics and prebiotics in the Probiotic Supplements Review >>

Withholding Immunosuppressive Drugs Boosts Immune Response to Vaccine

Temporarily withholding an immunosuppressive drug before and after an mRNA vaccine can boost immune response, according to a recent study.

COVID Risk & Immune Disease

Are people with rheumatoid arthritis, psoriatic arthritis, lupus, and other immune diseases at higher risk of severe re-infections? See the latest findings.

Low-Dose Prednisone and COVID Vaccines

Find out if taking low-dose prednisone reduces immune response to the COVID-19 vaccine.

Vitamin D and Allergy

Vitamin D is known to modulate the immune system. Having sufficient levels is associated with reduced risk of allergy and asthma. A recent study showed that giving vitamin D to pregnant women and their infants resulted in fewer infants being allergic to house dust mites and needing to see a doctor for asthma. For details, see "Allergy," as well as "Asthma," in the What It Does section of the Vitamin D Supplements Review >>

Zinc Concern

Zinc is a popular supplement right now due to COVID-19, but be aware that taking large doses of zinc for a long period of time can suppress the immune system by causing or exacerbating copper deficiency. Certain people may be more at risk for this. Get the details in the Cautions and Concerns section of the Zinc Supplements and Lozenges Review.

Does Ginseng Prevent Colds?

Ginseng may increase levels of certain immune cells in the body, but does this result in fewer colds? See what a recent study showed in the What It Does section of the Ginseng Supplements Review.

Symptoms of Zinc Deficiency

Zinc deficiency can cause a wide range of problems involving the skin, hair, mouth, and immune system. A recent report showed that it can also cause an eczema-like rash. Get the details and learn about the symptoms of zinc deficiency in the What It Is section of our Zinc Supplements and Lozenges Review. Also see our Top Picks for zinc supplements and lozenges.

How to Get a Third Vaccine Dose

A 3rd dose of the mRNA vaccines was authorized for immune suppressed individuals. Find out who can get it and how.

Extra Vaccine Dose

You can get an extra vaccine dose if you are immunocompromised or take medication that suppresses your immune system. Get the details.

Vitamin D for Asthma?

Can vitamin D supplementation reduce immune reactions to common asthma triggers, such as dust mites? Find out what a recent analysis showed in the What It Does section of our Vitamin D Supplements Review.

J&J Booster Vaccine

Data suggests that a booster dose of the J&J vaccine can significantly boost immune protection against COVID-19. Get the details.

5-HTP Concern

Three cases of eosinophilia-myalgia syndrome (EMS) have been reported among people taking 5-HTP, a compound related to L-tryptophan. EMS is a debilitating immune condition which has occurred in people taking L-tryptophan, but there were no previous reports of it being caused by 5-HTP. Get the details in the the updated review article on L-Tryptophan and 5-HTP >>

Vitamin D and Inflammation

A new study of elderly people given vitamin D showed little effect on markers of inflammation in the body. Correcting very low levels of vitamin D may be helpful, but further raising vitamin levels does not seem necessary for proper immune function. In fact, there may be some downside. For details about this and other uses for vitamin D (and our product test results), see the Vitamin D Supplements Review >>

Mixing Boosters for J&J Recipients?

Find out why some experts support mixing boosters for J&J vaccine recipients. Also see new research indicating that an mRNA vaccine may be the best booster for those already given a J&J-type vaccine.

Popular Probiotic -- What's In a Name?

Does the popular probiotic VSL#3 contain a different formula than used in the clinical studies supporting its benefits? Find out in the What to Consider When Buying section of the Probiotics Supplements Review. Also see our Top Picks for probiotic supplements.

Intestinal Benefit of Cocoa?

Cocoa flavanols may support intestinal health, according to an animal study with a cocoa powder that acted like a prebiotic. Get the details in the What It Does section of the Cocoa and Dark Chocolate Review. (Also see our Top Picks among cocoa and dark chocolate products.)

L-carnosine for Cardio Fitness?

Does research support L-carnosine supplementation for improving cardio fitness? Find out what a study showed among people with heart failure in our updated CL Answer about L-carnosine.

Recalls & Warnings (157)

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