These Two Common Supplements Are Best for Boosting Immunity, Experts Say

As cold and flu season ramps up, many people start looking for supplements to boost their immune system and avoid getting sick. 

When choosing supplements, consider your health needs rather than following blanket advice on the “best” immune-boosting supplements.

Generally, supplements may be “a waste of money” if you already follow a well-balanced diet that provides enough vitamins and minerals, said Marie van der Merwe, PhD, coordinator of the applied physiology and nutrition doctoral program at the University of Memphis.

Some people may lack specific nutrients that support the immune system, and supplements can help fill those gaps and support the body’s ability to fight infections, especially during cold and flu season.

Here are two immune-boosting supplements experts recommend—and the ones you can skip.

Two Science-Backed Supplements for Immune Health

The goal of using immune-boosting supplements is to strengthen your body’s ability to fight off an infection rather than avoid sickness altogether.

“There is no product to date that has been scientifically proven to prevent an infection. At most, what can be reasonably expected from these products is shortened duration and/or severity of cold symptoms,” Sevak Olmessekian, PharmD, a pharmacist at UCLA Health, told Verywell.

Vitamin C and zinc are two science-backed supplements that can help boost your immune system.

“There are some studies that have found taking vitamin C prior to the start of cold symptoms, in other words prophylactically, may shorten how long the symptoms last,” Olmessekian said. Similarly, “some studies have suggested that zinc could reduce the duration of common cold symptoms but has little effect on preventing a cold,” he added.

Vitamin D is another supplement that supports immune system function, yet nearly half of the world’s population has vitamin D insufficiency. Those who don’t get enough of it could definitely benefit from a supplement during cold and flu season, according to van der Merwe.

Vitamin E may also play a role in keeping the immune system regulated, though you don’t necessarily need to take a supplement for it. It can be found in nuts, vegetable oils, seeds, green leafy vegetables, and fortified cereals, among other foods.

Skip These ‘Immune-Boosting’ Supplements

Vitamin C and zinc are solid options for boosting immune health, but some other popular immune-boosting supplements may not work as advertised.

For example, while probiotics offer benefits like improved gut health, there’s no evidence they can enhance the immune system.

“I don’t think there’s a very clear study that shows if I take probiotics, I’m going to reduce my cold symptoms” or chance of getting sick, van der Merwe said. 

Similarly, quercetin is often touted as a cold and flu remedy, but its role is misunderstood, van der Merwe explained. “Quercetin lowers inflammation, but it doesn’t prevent you from getting an infection,” she said.

Echinacea is another common cold remedy, though experts know little about its effectiveness or how it might work, van der Merwe added.

Oil of oregano is also popular, but experts consider it a fringe suggestion for immune health. “I am not familiar with it and was not able to find any solid evidence supporting its use,” Olmessekian said.

Rather than relying on these supplements to prevent colds, focus on improving your sleep, nutrition, and hand hygiene, all of which are crucial for staying healthy during winter.