You might know this product, but how many people would run down and buy nutritional yeast flakes to take on their trip to the Amazon rainforest?


But that's exactly what I did. I was kind of desperate. After multiple trips to the jungle in Ecuador and Peru, I think the mosquitos know me. And tend to announce my arrival and invite their colleagues to dinner. In Manu Biosphere Reserve, I counted 100 mosquito bites on one arm.  I gave up counting bites on the rest of my body.

It's not like I walked around scantily clothed.  I took my long sleeve shirt off on the boats because the moving air kept the pesky critters at bay and it felt good to be in the fresh air. 

Let me explain all the remedies and repellents I've tried in combination with each other:


  • store bought pre-treated clothing (long-sleeve shirts and long pants)
  • home-made pyrethrin treated clothing, hats, shoes, socks
  • light colored-clothing is better than dark
  • deet-based lotions and pump sprays
  • citronella-based lotions, wrist bands and scented sticky patches
  • herbal soaps, shampoos and body lotions made with lemon grass and lavendar
  • beds shrouded in mosquito nets
  • I always wore socks and slippers/shoes of some kind in the lodges.

I prefer to use a natural product first, but honestly had to resort to deet-based products because itchy welts are quite annoying if not potentially dangerous considering all the diseases that are conveyed by mosquitos. The level of protection I got was dismal. I always came home with itchy welts. 

I wasn't expecting the yeast flakes to do anything significant. But I had nothing to lose, except mosquito bites, right?  I filled a zip loc baggy with the yellow powder and flew off to Peru. A few days before I flew to the deep jungle in Iquitos in northern Peru, I would fill my mouth with flakes each day.  You can buy capsules if you're not hardcore like me. And you can sprinkle flakes on your food if you must. 

After 4 days and 3 nights in the jungle in Iquitos, I did not get a single mosquito bite, and only 1 bug bite on my finger, which I believe to be from an ant. To say I am stunned is an understatement.  I wore the same light colored long-sleeve shirts and long pants that I normally wear. I used one of my deet-based bug sprays because honestly I wasn't expecting results this profound.

The only issue with an anecdotal story like this is will this treatment work for other people? I haven't scientifically proven anything, even for me.  Does it make a difference if you use flakes or capsules? Could one brand be better than another? When should people take it? How much should they take?

Will I try it again? Absolutely.  Do I recommend it for others? Yes, except for people who are "yeast intolerant" or prone to migraine headaches. Even if you don't notice any benefit as a mosquito repellent, most people can benefit from the protein, B vitamins and trace minerals. 

(Disclaimer: I am not a doctor or health professional. I'm sharing my personal experience in case others are interested. Please use this product at your own discretion)