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Will Brewer's Yeast Repel Fleas And Keep My Dog's Fur Healthy?

by Dani Johnson

July 5, 2013

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Above Image: My dogs, Bruiser and Maggie.

I have two dogs named Bruiser and Maggie. Bruiser is my eight year old Rat Terrier and Maggie is my boyfriend's three year old Jack Russel. These two adorable dogs are the focus of our lives while we're at home, and we do everything in our power to keep them happy, stimulated, and healthy. During the summer in the Southeastern United States, fleas are such a problem that they are abundant even though our dogs are on an oral flea medication. Spot-treatments are effective, but there are reasons why we don't want to use them. Our dogs do this thing we call "surfing" where they lie down on a soft surface, like the couch, and they roll onto their back and wiggle around, scratching their bodies all over. It's really cute, and they enjoy themselves so much. It's hard to get them to stop, too, until they're finished on their own terms. They also both lick and groom themselves quite often, and my dog is the type that will find a spot on his body and lick it until it's raw. I can keep his licking under control when I'm around, but it is out of my control when I am not. They also sleep in the bed with us, which isn't up for negotiation, and I surely don't want flea poison all over where we sleep. There are other reasons, too, but since spot-treatments work by staying on the fur and poisoning the fleas I think that's the biggest reason I stay away from them.

Above Image: Brewer's Yeast Tablets as a Dietary Supplement

Image Credit: LordToran

The most recent thing I've researched that is supposed to help control fleas in dogs is called Brewer's Yeast, and some of it is even infused with Garlic, which is thought to be bad for dogs bad for dogs. Brewer's Yeast is primarily used in making beer and certain breads, but it also contains lots of vitamins. Because of this, it has been a popular vitamin supplement for humans for a very long time. Check outSkeptoid Episode # 103to find out why vitamin supplements don't really do what is believed and how they have the potential to be harmful. People also give Brewer's Yeast to dogs, as a vitamin supplement, to maintain a healthy coat and even to repel fleas. Well, that's what they say it does, anyway. From what I've read, fleas are supposed to loath vitamin B1(Thiamine). Those pesky insects are also supposed to just hate the way yeast tastes, too. Apparently, if the dog ingests Brewer's Yeast regularly it will excrete B1 (Thiamine) laced with a yeasty odor that repels fleas. You can also sprinkle the Brewer's Yeast powder all over your dog's coat and it is supposed to have the same effect. This all sounds pretty convenient to me, by the way, I could not find any satisfactory evidence toward fleas hating anything in Brewer's Yeast.

It is worth mentioning that there is astudy by the Journal of Veterinary Medical Associationthat shows no difference between dogs who have taken Brewer's Yeast, as directed, and those who have not. But, what if you've given your dog Brewer's Yeast and it seems to work? It might seem like the Brewer's Yeast is working, but it's still worth considering that maybe your dog doesn't have fleas for some other reason. Try to find any reason at all that might explain the absence of fleas. Maybe there just aren't many fleas in your area. Then, try experimenting with taking the dog off of the supplement and monitoring the fleas.

Above Image: This is just a picture of a random house that I found on Wikimedia. The point is that their yard is neat and there aren't any overgrown shrubs or other plans resting against the house.

Image Credit:Lisa Heindel

Based on my research and personal experience, I have found that the best chemical-free way to reduce the population offleas is to maintain a clean house and trimmed yard. Vacuum couches, beds, carpets and curtains often. Keep any plants or shrubs that are growing close to the house as neat as possible; fleas will be more likely to get into your house if their home is laying against it. Brush your dogs every single night, even if they are short haired, to get off any fleas that may have accumulated during the day. It might also benefit to brush the fleas off of your dogs anytime they go outside, but I know that may not be practical in some homes. Sometimes, even with flea medication, you just have to bear it through the worst part of the season. Once the fleas go dormant for the winter it's time to get busy sucking up all of the dormant flea eggs hidden in the soft spots of your home. Vacuum everything and be sure to throw the vacuum bags in the garbage outside of your house. Pay special attention to the dog's bedding or anywhere he/she spends a lot of time lying around on. If the dog sleeps with you in the bed, it is crucial that you wash the bed sheets very often. Not just because of fleas; dirt and dog hair accumulate rapidly in any soft bedding that dogs rest on. The best way to avoid the "residue" is to clean it off regularly.

Either way you go, what really matters is the health of your dog. It is definitely worth researching every single thing you put in your best friend's body, just like it's worth researching everything you put in yours.

by Dani Johnson

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