By feeding your animals a high-quality, natural diet, free of additives and preservatives, you improve their health and dramatically increase their protection from fleas. A healthy animal does not taste or smell as good to fleas. A natural diet can be enhanced with nutritional supplements such as Nupro Dog and Cat Supplement, the Animal Essentials line, Herbal Multi-Vitamin Powder (overall health support), Plant Enzymes and Probiotics (digestive aid), Omega 3 Plus (an essential fatty acid supplement aimed at skin, coat and heart health). Both Nupro and Animal Essentials supplements can enhance your pet's health and thus strengthen their immunity.

Brewers Yeast and Garlic added to your pet's diet will help keep fleas away also. The important flea-control ingredient in brewer's yeast is thiamine (vitamin B). A level of one milligram (1 mg) of thiamine daily for each five pounds of your pet's body weight is ideal. For an average-size cat, this would translate to one teaspoon of brewer's yeast; for a large dog, you might administer one tablespoon of brewer's yeast supplemented with a B-complex vitamin pill. Brewer's yeast can also be dusted on externally as a flea powder. (If your pet licks some off, there's no harm done.)

A third important flea-fighting dietary supplement is zinc. This mineral is essential for healthy skin, but is lacking in many pets' diets. Use chelated (pronounced key-lated) zinc: 10 mg daily for cats and small dogs; 20 mg for larger canines.

These dietary supplements will require close to a month to build up to flea-fighting levels in a pet's skin. So start them in the spring before you find yourself in the midst of a severe flea invasion.