Why is brewer's yeast sometimes fed to dogs and cats as a supplement?

Brewer's yeast hardly sounds like something meant for your pet; it's a one-celled fungus, used to make beer.

The pet industry, however, offers it as a dietary supplement. Brewer's yeast contains b vitamins, zinc, proteins, and amino acids. It's touted for boosting the immune system, and promoting healthy skin and a shiny coat. It's also been sold as a flea remedy.

But some animals are allergic to yeast, and diabetic pets must avoid it, as yeast can interfere with the insulin cycle. So before trying a new supplement, talk to your veterinarian. He or she will help determine if the brewer's yeast needs to stay in your brew, or could be a beneficial component of your pet's diet.

– Dr. Larry McDaniel, DVM for the “Purina® Animal Instincts” Podcast Series

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