Yes.
I gave brewers yeast in combination with garlic power to our cat, as part of his everyday diet, for his entire life (almost 29 years) and he never had fleas, ticks or any other biting bug I ever knew of.
Shortly after returning to a rural area in the north-east I added brewers yeast and garlic powder to both my own diet and that of my husband.
It has not totally eliminated bites from mosquitoes, black flies and their blood-sucking relatives. However considering the fact I was usually the one who suffered the worst from such things I can say I rarely get bitten these days.
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You need to begin taking Brewer's yeast and vitamin B tablets six weeks before summer to avoid the bites from midges. Brewer's yeast is also good for you and your pets.