There are lots of popular “remedies” that promise to cure or shorten the common cold.
But experts say most don’t live up to the hype.
Vitamin C and echinacea have not been found to help cold sufferers.
Limited research shows that zinc and garlic might help, but probably not in a meaningful way.
You already know that there is no cure for the common cold. Still, when you’re saddled with aches, chills, sneezes, and sniffles, you’re probably desperate to try anything that offers the promise of relief.
There’s just one problem: Experts say some of the most popular cold “remedies” aren’t actually proven to work — and aren’t worth your money.
Here are four not-so-effective treatments you should know about.
1. Vitamin C
There may be shelves full of supplements claiming otherwise, but vitamin C will not help your cold go away faster.
“The myth lives on, despite the fact that the truth about vitamin C has been out there for a long time,” Timothy Caulfield, professor of health law and science policy at University of Alberta and member of the True Health Initiative, told INSIDER. “People still seem to think it works. It’s almost part of our culture.”
But the science on this issue is clear: Back in 2007, researchers pooled the results of 29 different studies looking at the effect of vitamin C on colds. They found that taking vitamin C once a cold has already started doesn’t do anything special. Even worse, super-high doses of vitamin C can cause diarrhea, nausea, and abdominal cramps, according to the National Institutes of Health (NIH).
As dietitian Andy Bellatti previously told INSIDER, “if you do have a cold, stay hydrated and get enough rest. Don’t go to work and pound [vitamin c].”
In 2014, researchers analyzed 24 different studies involving more than 4,000 participants, all testing whether or not echinacea could treat or prevent a cold. The authors’ conclusion was that, “echinacea products have not been shown to provide benefits for treating colds.”
“The evidence is very very weak that it has any kind of effect,” Caulfield said. “I would not bother.”
There’s really only one high-quality study on garlic and the common cold. That study, published in 2001, followed 146 people for three months. Half took a garlic supplement every day, and half took a placebo.
The people taking garlic actually did get fewer colds: Over those three months, there were 24 cases of the common cold in the garlic group and 65 cases in the placebo group. But some garlic-takers experienced skin rashes and odor, and taking garlic didn’t dramatically shorten colds — they lasted about the same amount of time for people in both groups.
Zinc is a nutrient that our bodies need — and it’s available in a bunch of different foods. It’s also known for its supposed cold-shortening powers.
Back in 1984, a study found that zinc lozenges reduced the duration of a cold. Since then, however, studies on zinc for the common cold have had conflicting results, according to the NIH. Caulfield said he thinks the zinc hype is likely overblown. “If you look at the body of evidence,” he said, “[it’s] not very promising.”
Although some experts still recommend zinc, doctors from the Mayo Clinic, Harvard School of Public Health, Cleveland Clinic and Indiana University School of Medicine have expressed uncertainty about its benefits. The bottom line is that zinc might work, but it also has known downsides. It makes some people nauseous, for one, and taking too much of it can be toxic to your body, the NIH explains.
That points to a larger truth about all supplements, including ones with zinc, garlic, vitamin C, or echinacea: even if they’re natural and available over the counter, we can’t always trust that they’ll be safe.
“The regulation is not great in the supplement industry,” Caulfield said. “The studies have shown that the supplements are often contaminated or they don’t contain the ingredients that they claim to contain. So you have that part of the story. [When you] add to it that there’s no evidence that they work, why spend your money on these products?”