Vitamins and supplements can offer certain health benefits for some people — but unfortunately, buzzwords, false claims, and a lack of regulation often make it difficult to find an option that's effective and safe. The best vitamins and supplements to boost the immune system contain certain key ingredients backed by science but leave out unwanted additives. The options aren't always easy to narrow down, so New York-based research neuroscientist Nicole Avena, Ph.D., Ontario-based naturopathic doctor Yelena Deshko, N.D., and Jacksonville, Florida-based Anthony Capasso, M.D., and consultant to PureLife Organics, weighed in to share some of their favorite immune-boosting ingredients and offer advice for shopping for supplements in general.
To choose the best active for you, consider your lifestyle and needs. "Zinc helps to fight off invading bacteria and viruses," Dr. Capasso explains in an email to Mic, so it may help if you're often exposed to germs. He describes immune defense-boosting vitamin C as "a potent antioxidant," which can scavenge free radicals that result from exposure to pollution and harmful chemicals. Vitamin D is important because it "regulates multiple functions in the body from brain health to bone health," according to Dr. Capasso — and a deficiency of vitamin D often comes from lack of sunlight. He explains that B vitamins "are synthesized from the bacteria and yeast in our gut," but since we can't make these vitamins without the right foods, they're usually lacking in an unbalanced diet. Stress, poor sleep quality, smoking, and alcohol can also weaken the immune system as a whole.
If you're looking for an immune-boosting supplement that can also promote relaxation, try L-theanine. Deshko writes, "Research suggests that L-theanine, a compound found in green tea, can help T cells (a type of immune cell) defend against invading bacteria," Deshko writes — adding that the compound might help you relax, too.
And when it comes to botanical extracts, consider aged garlic and elderberry, especially during cold and flu season. According to Deshko, aged garlic extract "may enhance immune cell function and may be partly responsible for the reduced severity of colds and flu reported by participants of one study." Dr. Avena also notes that "elderberry has potential benefits in reducing recovery time after colds and the flu."
Of course, it's always a good idea to consult a medical professional before taking any new vitamins or supplements. According to Dr. Capasso, you may want to consider testing for vitamin deficiencies if you follow a limited diet, regularly consume alcohol, have digestive issues or celiac disease, or take a lot of medications.
As you're shopping, you'll also want to keep an eye out for unwanted fillers to ensure you're getting a quality product. "Many brands of supplements contain artificial colors, flavors, and other various unhealthy ingredients," according to Deshko.
With all of that in mind, here are some of the best vitamins and supplements for boosting your immune system.