Q. Years ago my father heard that large doses of B vitamins (sorry, I don’t remember which ones) would repel mosquitoes. Apparently it changed the smell of his skin because my mother commented that he smelled so bad that she wouldn’t bite him either!
A. Taking large doses of vitamin B1 (thiamin) has long been recommended as a way to repel mosquitoes. The scientific evidence to support this practice is sparse.
We heard from one European-trained physician, however, who learned this approach in medical school. He prescribed it for many patients in the tropics, all of whom found it helpful. He noted that it makes perspiration smell a bit like yeast, but that the smell drives the mosquitoes away.
We only wish that scientific studies supported this approach. Sadly, they don’t. That might be because some people really get benefit because of their unique body chemistry while others do not. The negative studies may not take this peculiarity of human biology into account.
Here is one Q&A worth reading:
Q. I read about people getting bit by mosquitoes and I want to tell you my experience. For the last 20 or 30 years I have been taking (along with other vitamins) a half tablespoon of brewers yeast. Since I started taking this every morning I have never been visited by any mosquitoes.
My wife gets bites during the warmest part of the summer, but mosquitoes leave me alone. Maybe it is my Swedish blood they don’t like. They must love my Sicilian wife!

A. Yeast is rich in B vitamins, especially thiamine. Anecdotal reports and some antiquated research suggest that this nutrient may repel mosquitoes. But not everyone benefits. We suspect that body chemistry might have something to do with the effectiveness of this approach.
If you want to kill mosquitoes in your vicinity, we have an amazing remedy to try.
When all else fails and you have been bitten and are itching like crazy here is a hot water remedy to the rescue.

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  1. P H
    Reply

    Does anyone know if B1 will help get rid of the scabbie mite,they are driving me crazy

  2. SFD
    Reply

    My daughter and I took high doses of Thiamine 2 days before a day trip to a tropical island known for its sand flies and mosquitoes. The other 10 in our party were covered with sand fly bites. We did not get one bite that day.

  3. Mark
    Reply

    I used to sit outside in the summer with my brother-in-law. The mosquitos would be eating me alive. They never would bother him. He would jest that he wishes a mosquito would bite him so he knew what people were complaining about. The only thing that I could think of that could repel the Mosquitos that he did was he ate large doses of hot peppers. He raised his own garden and would eat hot peppers with every meal. Does anyone know of someone who eats hot peppers and has never been bitten?

  4. Michael W.
    Reply

    It worked for my family. We lived in Dar Es Salaam, Tanzania for 11 years. After the first two years we stopped taking Malaria prophylaxis and overdosed on B-Vitamin instead. In particular, “Yeast Pills” and B1. Although living in an area where Malaria was rampant, none of us contracted Malaria or were bitten by Mosquitoes.

  5. allison
    Reply

    I totally agree. GARLIC is a wonderful deterrent. I had a mosquito bite me at night, two nights in a row. The bites were big, red, and itchy and I stayed up at night even trying to catch the mosquito because I just couldn’t take any more bites after that. So, I remembered hearing about garlic, and I chopped some garlic and lightly cooked it with my spaghetti and I got no bites. I did that for my dinner meals for a few nights in a row, and I didn’t get bitten again! It actually went very well with tomato dishes.

  6. Sandy M
    Reply

    When I was young, mosquitoes loved me. In my 30s and 40s, they left me alone. When I went through menopause, they started loving me again. It’s definitely body chemistry.

  7. Anne T.
    Reply

    I was in New Hampshire for Memorial Day Weekend a long time ago and was bitten by a Black Fly on an eyelid which swelled up like a ping pong ball. This was before Benadryl was available OTC.
    My husband took me to the ER where I was given an injection, and a pill prescription. The doctor said, “I ORDER you not to come to NH between Mothers Day and Fathers Day! But if you do, you should take maybe 50mg of Thiamine a few days ahead and while you’re here.”
    I did and he was right. It’s dangerous to take that much for very long. It will deplete the other B vitamins in your system. B’s need to be balanced. For mosquitos, I just spray some bug repellent, but I don’t need it very often. I try to keep some Benadryl handy too.

  8. Paul G.
    Reply

    Hi, As I remember it, B-1 1000mg per day was used to repel black flies and people who vacationed in Canada took it to repel those hungry biting black flies. pg1246 o&o

  9. Cate
    Reply

    I spent a week in the Cayman Islands several years ago and was miserable from sand fleas biting me. I was miserable. A friend told me about taking B1 beginning a couple of weeks before going back the next year. I began taking them (50mg./day) and had no problem. I became an instant convert.

  10. MJW
    Reply

    Peripherally related might be cats and fleas. I once had two cats, one of whom was a magnet for fleas, while the other had nary a flea on her. Because they occupied the same spaces, and engaged in similar activities, I could only conclude that it was body chemistry.

  11. Cindy B.
    Reply

    Vick’s vaporub or generic equivalent take the itch away immediately.

  12. Conrad S.
    Reply

    Mosquitoes like me, for quick relief I put toothpaste on the bites as soon as I can. The itching and swelling goes away in a couple of minutes. We always keep a small sample toothpaste handy.
    Con

  13. heide
    Reply

    Since hearing about vitamin B-1 to repel mosquitoes, about 20 years ago, my husband and I have been taking 150 mg. daily and others are going crazy with the bug spray (keep that stuff away for me!!) we have NO problems with mosquitoes, especially on the golf course.
    Now that we live in Florida we take the vitamin daily but when we lived in NC we’d take it from April to November. The bugs don’t want to visit us as the other people complain about the bugs!!

  14. Cindy B.
    Reply

    I am certain my use of B-complex (2 “B-100’S” per day) keeps the mosquitos, fleas, etc., away from me. I rarely use any repellant yet never get bit. Once when up in the high country and really needing repellant, I found myself without it.
    I literally took at B-complex tablet, crushed it, mixed with a little water and rubbed it all over my body. Yes I was stained yellowish but the bugs sure didn’t bite! Taking it does change the skin chemistry to repel bugs, at least for me. They don’t like garlic either, which I also take.

  15. cpmt
    Reply

    Also taking or eating garlic…

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