According to Dr. Anthony Fauci, most "so-called immune boosting supplements" actually do "nothing." However, there are two vitamins Fauci does recommend to help keep your immune system healthy.
"If you are deficient in vitamin D, that does have an impact on your susceptibility to infection. So I would not mind recommending, and I do it myself taking vitamin D supplements," Fauci, 79, said during an Instagram Live on Thursday, when actress Jennifer Garner asked Fauci about immune-boosting supplements.
(In fact, researchers at the University of Chicago Medicine recently found a link between vitamin D deficiency and the likelihood of being infected with Covid-19 — those with an untreated deficiency were more likely to test positive. "Vitamin D is important to the function of the immune system and vitamin D supplements have previously been shown to lower the risk of viral respiratory tract infections," David Meltzer, chief of hospital medicine at UChicago Medicine and lead author of the study said in a press release on Sept. 8.)
In addition to vitamin D, Fauci said that vitamin C is "a good antioxidant." "So if people want to take a gram or two at the most [of] vitamin C, that would be fine," he said.
(Vitamin C "contributes to immune defense by supporting various cellular functions" of the body's immune systems, according to 2017 study published by The National Institutes of Health, and vitamin C also appears to prevent and treat "respiratory and systemic infections." according to researchers.)
But "any of the other concoctions and herbs I would not do," Fauci said.
During another interview with actress Tiffany Haddish released on Sept 4., Fauci said in clinical studies most "so-called" immune-boosting supplements didn't really help people unless they had some sort of a deficiency. If fact, a lot of these herbs "either do nothing, or, if you take too much of them, they harm you," Fauci told Haddish.
Overall, the best way to boost your immune system is to get good sleep and exercise, Fauci said. "Those are the things that are so much better than a bunch of herbs that really have never really been shown to do that," Fauci told Haddish.
In March, Fauci, who has been a member of the White House Covid-19 task force, said he often worked 20 hours a day dealing with the pandemic. He credited his wife of 35 years, Christine Grady, a nurse bioethicist, for reminding him to take care of himself. (Grady told CNBC Make It in April that she tried to push to get him to get proper rest and to drink water during his long days.)
And Fauci said in the July issue of InStyle Magazine that he also made time to power walk at least 3.5 miles a day to relieve stress and maintain good health during the pandemic. Fauci, who has been director of the National Institute of Allergy and Infectious Diseases since 1984, used to run up to seven miles a day at lunchtime, but switched to power walking because it's gentler on his body.
On Thursday, Fauci warned Americans that they should be prepared to "hunker down" until 2021 thanks to coronavirus, because the fall and winter are "not going to be easy."
As of Monday morning, more than 6.5 million people have been inflected with Covid-19 in the U.S. and at least 189,500 have died, according to Johns Hopkins.