Forget vitamins: Fauci says the 3 best things 'to keep your immune system working optimally' cost nothing

• Dr. Anthony Fauci supplements his diet with two vitamins: C and D.

• For the general public, he recommends getting enough sleep, maintaining a healthy diet, and avoiding or alleviating stress as the three most potent ways to keep your immune system strong.

• "That is much more healthy living than giving yourself supplements of anything," he said.

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Dr. Anthony Fauci is, at this point in the pandemic, getting used to having his words twisted around into things he never really said.

"Always, always it'll get taken out of context and misconstrued," the director of the National Institute of Allergy and Infectious Diseases said during our recent lunchtime chat. "I've gotten used to living with that."

Recently, the issue came up when he told the actress Jennifer Garner that he takes two supplements: vitamin D and vitamin C.

"If people want to take a gram or so of vitamin C, that would be fine," he said at the time.

Related: Fauci says ‘unlikely’ there will be a pre-election vaccine

Certain corners of the internet started touting his words as evidence that he knows something we don't, as if he were hiding information about a silver bullet.

But he was not mandating the practice for the general public, nor was he suggesting popping vitamins is a surefire way to avoid getting sick. Rather, he said, he was just answering a question.

"I had made it very clear when people asked about what vitamins I take, and I try to explain it," Fauci said.

If you ask him, Fauci will still say, without question, the best ways to control the pandemic are the measures he's been recommending endlessly for months: good hand hygiene, mask-wearing, and social distancing.

For some people, adding a little extra vitamin D might make sense.

'There is good evidence that if you have a low vitamin D level, you have more of a propensity to get infected'

"Sometimes people when they don't get out in the sun a lot, they're deficient in vitamin D — so my vitamin D level was generally low," Fauci said. "I started taking vitamin D supplements, and now my vitamin D level is normal."

We know from many scientific studies that being deficient in vitamin D can put you at greater risk of infection, and that finding has held true again during the coronavirus pandemic.

"There is good evidence that if you have a low vitamin D level, that you have more of a propensity to get infected when there are infections around," Fauci said. "Those data are pretty good data."

In addition to reducing inflammation in the body, vitamin D also helps our bodies absorb calcium, keeping bones healthy and strong, so it's good for people of all ages and colors to make sure they're getting enough.

But that doesn't mean everyone needs to run out and get a multivitamin. Most health experts agree those are virtually useless pills.

"When you talk about the multiple multivitamins and the herbs and the things that people do to so-called boost immunity, that really doesn't boost immunity and may have a better placebo effect than anything else," Fauci said.