What to Eat to Prevent the Flu
Are there foods and nutrients that can help bolster your defenses against the flu? Nutrition Diva sorts the facts from fiction—plus one criticial factor that's often overlooked.
This has been one of the worst flu seasons in a decade—and there are plenty of nasty coughs and colds going around as well. Is there anything you can do—nutrition wise—to bolster your defenses?
Does Red Wine Protect Against the Flu?
For example, you may have seen the story that went viral last week claiming that drinking wine can keep you from getting the flu. Alas, this was another example of headline writers run amok. In fact, after I posted their original headline (“Drinking wine will stop you from getting flu”) as a particularly egregious example, the UK’s Independent updated their headline to one that’s slightly less untrue. (“Drinking tea and wine could keep flu at bay”). But only slightly.
Guess what the study in question did not involve? Wine. That’s right. No wine was harmed (or even consumed) in the course of this particular study. No tea, either, for that matter. The researchers were testing the effects of resveratrol, a compound found in wine but also in tea, grape juice, and peanuts. The experiments were being done on mice. And the resveratrol did not keep the mice from getting the flu, because all of the unfortunate mice in this study already had the flu. But the resveratrol did seem to help the mice fight off the infection.
This is not the first study to suggest that resveratrol might be useful in fighting influenza and other viruses, by the way. There’s even research to suggest that moderate consumption of red wine could reduce the chances of catching the common cold.
See also: Is Drinking Alcohol Good For You?
But should you come down with the flu, drinking wine is not recommended. For one thing, you’d probably die of alcohol poisoning long before you got to the amount of resveratrol tested in these studies. Meanwhile, drinking alcoholic beverages will dehydrate you, which is going to make you feel worse, not better. If you want to increase your resveratrol, drink tea or grape juice or eat peanuts. It may not help, but it probably won’t hurt.
Can Vitamin D Protect Against the Flu?
Taking a vitamin D supplement could offer modest protection against the flu. Examining studies involving more than 10,000 people, researchers found that taking a vitamin D supplement reduced cold and flu infections by about ten percent. Among those who were low in vitamin D, however, taking a supplement reduced infection by a much more encouraging 50%.
Vitamin D is inexpensive, exceedingly safe, and has other benefits such as helping build strong bones. And low vitamin D levels are extremely common, especially during winter—otherwise known as flu season. Although it’s not a magic bullet, I’d say a vitamin D supplement is a no-brainer.
Can Probiotics Protect Against the Flu?
Probiotic foods and supplements might also offer a bit of extra protection. A review of about a dozen studies found that probiotic supplements could cut your risk of cold and flu almost in half and trim a few days off your recovery to boot. The caveat here is that the available studies aren’t of the best quality. Also, they weren’t all testing the same probiotic. There are thousands of strains of friendly bacteria out there, and they don’t all have the same benefits. Some might be better at protecting against infection than others.
This is why my strategy is to eat a variety of probiotic foods, including yogurt, kefir, miso, and fermented vegetables. The more different probiotic foods you consume, the wider the variety of microbes and the better your chances of getting the right ones. In fact, some studies suggest that the diversity of your gut population may be more important than which specific bug you have on board.
But once you’ve stocked the pond, you need to be sure to feed the fish (as it were). And that’s why it’s important to eat plenty of prebiotic foods as well. Those include legumes, nuts, whole grains, and other sources of fiber that provide sustenance for those friendly bacteria.