It’s winter, as you can see from your window. COVID-19 is circulating at record levels across much of the country. Keeping our immune systems healthy has taken on new meaning as many of us hope to ward off flu and winter colds, as well as worrisome variants of the virus that causes COVID-19, whether Delta or Omicron.
Not surprisingly, marketers are taking advantage of our concerns. An entire cottage industry is dedicated to chews, pills, and powders that claim to “boost” or “support” your immune system. Some people even claim that healthy eating and vigorous exercise are all you really need to avoid disease. But are any of these claims true?
The best strategies to stay healthy
I asked Michael Starnbach, a professor of microbiology at Harvard Medical School, for advice on what can help us stay in good health this winter.
“Vaccination, skepticism about other products that claim immune system benefits, and staying away from places without universal masking are the best strategies,” he says. That is why these approaches count.
to be vaccinated
When it comes to boosting your immune response, it’s best to get the COVID vaccine and booster along with other recommended vaccinations. Think of vaccination as a cheat sheet for your immune system. When a viral invader enters your body, your immune system prepares to fight. But first it has to figure out what’s attacking, which takes time – time to allow the virus to keep multiplying in your body.
A vaccine brings the immune system closer to the invader early on and allows them to develop a battle plan. So if the virus shows up at the door, your immune system can respond quickly, which may mean no symptoms, or at least prevent serious illness. A booster shot is a refresher course to keep those lessons fresh.
While it’s possible to get infected yourself after a vaccination, your immune system is primed to clear the virus more quickly, making the infection far less likely to be serious or life-threatening. “We should get all available vaccines and boosters so that if we get infected, we have a better chance of a mild case,” Starnbach said.
A variety of vitamin formulations and probiotics claim to boost or support your immune system. And while some of these claims contain a grain of truth, the overall picture is that they often don’t work. For example, vitamins help immune function, but really only in people who are vitamin deficient—not the average, healthy adult.
Probiotics are also promising. This mini-universe of organisms that live in your gut, called the microbiome, plays an important role in immunity. But experts don’t know enough about this role to develop a product that can manipulate the microbiome to boost immunity. That could change over the next decade — but for now, you should view probiotic claims with a healthy dose of skepticism, says Starnbach.
Ultimately, nothing is better for keeping you healthy than avoiding exposure to a virus entirely. Wearing a mask is not on anyone’s favorite list, but it can help reduce the risk of spreading COVID (and some other viruses) to unvaccinated people, including vaccine-eligible children and people with the immune system to reduce deficiency patients who are not adequately protected by the vaccination, says Starnbach. Masks are most effective when everyone around you is wearing one. “We now clearly know that the best way to prevent the infection of unvaccinated people is to wear masks indoors,” says Starnbach.
Practice good health habits
But what about exercise and good nutrition? Do they play a role in supporting your immune system?
The answer is yes. Strategies to improve your overall health are never wasted. Healthy people are more resistant to disease and often do better when infected. Good health habits can help your immune system work at full speed. Exercise and good nutrition aren’t the only habits that can help. You should also try to get consistent, quality sleep and manage your stress levels. Lack of sleep and chronic stress can impair immune function.
However, if you hope to avoid COVID-19 and other viruses, these strategies should be used in addition to vaccinations and other protective measures – not as a substitute.
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