The Yeast Question

By: Tom Cameron, DVM

A common question with our pet foods is “why is Brewer’s Yeast added?”

Isn’t yeast a bad thing? I hear so much about ‘yeast overgrowth,’ ‘yeast infections,’ Candida yeast, etc. If yeast causes so many problems, why would you add Brewer’s Yeast as an ingredient in pet foods?

It turns out that there is more to yeast than health problems. As with people, books, food, movies – there are good ones and bad ones. Here are some facts about yeast:

  • There are over 1500 types of yeasts in the world, and they are widely distributed in nature. Yeasts are normal residents of soil, vegetation, marine and other water environments. Yeasts are some of the most thoroughly researched microorganisms.
  • Some yeasts live naturally in and on man and animals.
  • Some are beneficial to our health, some cause health problems (pathologic yeasts).
  • Ancient Egyptians used yeast over 5000 years ago to make bread and to brew alcohol.
  • Most of the important scientific discoveries have been made using yeast cultures. Yeast cultures are used to make wine and ethanol. Yeast cultures are also used to clean up toxic waste and improve aquarium environments.
  • Yeast cultures play a big role in the healthy practice of fermenting foods, like sauerkraut, pickles, kimchi, kombucha, kefir, kvass, and other healthy foods.
  • Nutritional Yeast – Yeast can be a nutritional supplement, providing vitamins, minerals, protein, and cofactors needed for growth.

All yeasts ferment sugars, and they produce by-products from that fermentation. They are categorized by the by-products they produce. Beer, wine and whiskey producers use yeasts that ferment sugars to alcohol (brewer’s yeast). Bread bakers use yeasts that produce carbon dioxide gas, which causes bread to rise (baker’s yeast). Bakers and brewers use different combinations of yeasts and sugars to get different flavors, textures, and colors in their products.

In both humans and animals, there are yeasts and bacteria that support health, and some yeasts and bacteria cause diseases. Both sides are constantly ‘at war’ with each other, fighting for control. When the ‘good guys’ are in control, good health results. When the ‘bad guys” gain control, sickness is the result.

Yeasts that cause health problems are called pathogenic yeasts. Some pathogenic yeasts you might recognize include ‘ringworm’ and Candida albicans. These pathologic yeasts cause health problems due to the by-products they produce. Pathologic yeasts are ‘opportunists,’ which means they grow and thrive when the local environment allows it. Candida yeast infections occur when the local environment becomes more alkaline than normal, or the normal bacterial population has been interfered with (weakening the ‘good guys’). Pathogenic yeasts grow best when the immune system is ‘run-down.’ Yeast infections can occur when an individual is run-down, has been sick, has been over treated with antibiotics, or when the diet is too high in sugar.

Brewer’s yeast (also known as Nutritional Yeast) is a common nutritional supplement. Brewer’s Yeast has been heated to ‘kill’ the yeast, and it is not an active, fermenting supplement.

Brewer’s Yeast contains a rich combination of valuable nutrients:

  • B-complex vitamins – important promoter of nerve health, supports muscle tone, blood sugar disturbances, red blood cell building, heart health
  • Proteins (amino acids) – important building blocks for tissue healing, repair, and maintenance.
  • Chromium – critical mineral for blood sugar balance, has insulin like activity
  • Trace minerals – major components of all enzymes, critical for nerve function, structural components of teeth, bones, ligaments.!
  • Fiber – supports digestive health, helps manage blood sugar levels, encourages probiotic growth and activity, immune system support

Nature’s Logic adds Brewer’s Yeast to their pet foods to improve the nutrient value, taste, and texture. Brewer’s yeast has been shown to help with diarrhea, respiratory tract infections, influenza, and Type 2 Diabetes. Brewer’s Yeast does not cause yeast infections, or make yeast infections worse. The many benefits of Brewer’s Yeast make it a safe and excellent addition to Nature’s Logic Pet foods.