Mosquito Tips - Vitamin B1 and Thiamine

Rumors say that taking large doses of vitamin b1 - Thiamine - helps to ward off mosquito bites. Unfortunately, actual tests show that the mosquitoes don't care about your state of health.

One such email says "Bob, a fisherman, takes one vitamin B-1 tablet a day April through October . He said it works. He was right. Hasn't had a mosquito bite in 33 years. Try it. Every one he has talked into trying it works on them. Vitimin B-1 ( Thiamine Hydrochloride 100 mg.)"

First, I wouldn't trust someone that misspells "vitamin" and who relies on Bob the Fisherman for medical advice.

Don't get me wrong. B-1 is an important vitamin and is good for your heart and nervous system. But the US RDA for B-1 is 1.5mg. To take 100 times that amount daily because of an urban legend is really unwise.

If it were TRUE it might be worth looking into the medical risks and tradeoffs. But since research studies show that taking B-1 has no impact at all on mosquito bites, it's best to stay with healthy doses of vitamins. There are many times that too much vitamin is far more dangerous than too little.

I recently had a visitor write me an email containing both misspellings and swearing. His name was Tim. His contention was that "This has been proven in tests after tests". He said, "B1 is a water soluable vitamin, so we put it in a patch to keep a metered dose. Now we have 36 hours of protection."

I'm not sure what Tim's point was in mentioning that B1 is water soluable. All Vitamin B and Vitamin C family of vitamins are water soluble. Really, what that primarily means is that excess amounts of that vitamin are easily peed out in your urine. In fact, you pee it out so easily that many studies show that you only actually absorb 10-15% of a vitamin pill you take - the rest gets peed out. That is often why you take "mega-doses" of Vitamin C, because you are trying to get your body to absorb as much of it as it possibly can. It is said by many doctors that using these vitamins in large doses really just leads to having very expensive pee.

The whole point of Bob the Fisherman's advice was that you overdosed on thiamine, and the excess would be excreted by your system. Most would go out in your pee, but some would sweat out of your pores, therefore covering your body in a thin layer of thiamine that would apparently ward off the mosquitoes. Even if we assume there IS a warding effect, the only way to have the system work is to create an overload situation in your body so that there is so much thiamine that your body is not only peeing it out, that it is also excreting it through your pores as well. If Tim can truly create this overload situation for 36 hours straight, I wonder just how many mg of thiamine he is pumping into the skin at that one patch point, for it then to distribute around the body to all cells.

For those curious just what thiamine does for you in healthy doses, it helps keep away beriberi, just as taking vitamin C helps to keep away scurvy. Beriberi is found frequently in areas where people live on polished rice, as they tend not to get enough thiamine in their diet with that base food. The polishing process removes most of the thiamine from the rice kernel. Those who are deficient end up with nervous system problems and heart problems.

But, back to the mosquitoes. I am very curious about these "tests after tests" that have proven scientifically the value of thiamine in warding off mosquitoes. I do know for a fact that the Canadian Military explicitly tested Vitamin B-1, hoping for an easy mosquito repellent, and their studies proved it did NOT work. I also know that the U.S. Centers for Disease Control and Prevention explicitly state that Vitamin B-1 does not repel mosquitoes, based on their own tests. I trust those two organizations to have tested thiamine thoroughly. I would of course be very interested in seeing the publication holding the studies being quoted by Tim. I will gladly forward that research along to the Canadian and US government, as they apparently have missed reading the studies.

With the many solutions that are proven by studies to work, I'm just not sure why someone would stick a patch of Thiamine on them and overdose on it for 36 hours straight. The very thought makes me nervous. I just checked and using more than the US RDA amount of Thiamine is described with these words:

"Symptoms of a thiamine overdose may include a feeling of warmth, weakness, sweating, nausea, restlessness, difficulty breathing, tightness of the throat, bluish colored skin, and death."

Once again, the US RDA is 1.5mg. The "Bob the Fisherman" amount required to ward off mosquitoes is 100mg. I'm not sure how much Tim the Patch Man is applying to his body.

I obviously test out all of these different products myself, and have found no difference in mosquito attention when using Thiamine vs without. If Bob or Tim want me to run more tests, I'm game to try. But instead of swearing and quoting mysterious studies with no names, I would like: 1) messages that are written with some care and 2) actual study documentation before I proceed.

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