Fact check: No, vitamin B1 supplements do not repel mosquitoes

Rick Rouan, USA TODAY
·3 min read

The claim: Taking B1 vitamin supplements will repel mosquitoes

An old myth about how to repel one of summer’s most annoying pests is again buzzing around social media.

With camping, backyard barbecues and other outdoor activities in full swing, the claim that vitamin B1 supplements can help repel mosquitoes is getting new life online.

The claim has circulated for years, but it resurfaced on Facebook again in 2021.

“This is so simple,” one Facebook user wrote on July 29 in sharing a link that includes the claim to more than 5 million followers. Another user shared an identical post to more than 3 million followers on June 12.

The post links to an undated guide on the website RemedyDaily touting B1 for its mosquito repellant qualities, even though it acknowledges that it is not scientifically proven to be effective.

In fact, researchers have demonstrated it doesn’t affect mosquito attraction. Studies of subjects taking oral B1 vitamin supplements and wearing a B1 vitamin patch found no effect on mosquito attraction.

RemedyDaily did not respond to a request for comment.

A mosquito perches on a subject's skin.
A mosquito perches on a subject's skin.

Research says B1 not effective mosquito repellant

RemedyDaily’s post is one of many across the internet boosting vitamin B1’s alleged mosquito-repelling properties. Vitamin B1 is also known as thiamine.

It recommends a daily dosage of vitamin B1 and notes it can be found in foods that can be incorporated into your diet. It suggests taking B1 supplements two weeks in advance to realize the benefits. The post also offers some other tips, including natural repellants.

The post has been bubbling around Facebook since at least 2017.

But researchers who have studied the effect of the supplement on mosquito attraction are clear: It has no effect.

A 2005 study in the Journal of the American Mosquito Control Association, for example, tested whether taking vitamin B supplements affected attractiveness to mosquitoes.

“We found no effect of vitamin B supplementation,” according to the study by University of Wisconsin researchers.

In 2015, researchers from New Mexico State University published a study in the Journal of Insect Science comparing the effects of eight commercially available replants, two fragrances and a vitamin B patch on attraction to a human hand for two species of mosquitos.

The study confirmed a study from 1969 in determining “the vitamin B patch had no effect on either species.” In fact, the perfume, Victoria’s Secret Bombshell, was more effective at repelling mosquitoes than the vitamin B patch.

Our rating: False

The claim that taking B1 vitamin supplements will repel mosquitoes is FALSE, based on our research. Researchers have studied the effects of vitamin B1 on mosquito attraction and found it has no effect, whether taken orally or by wearing a patch.

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This article originally appeared on USA TODAY: Fact check: No, vitamin B1 doesn't repel mosquitoes