Human nutritionists stress the importance of variety as a means of achieving a balanced diet. Rotation of meats, vegetables, grains and oils is thought ensure the necessary needs of the body. Many feel the same is true for homemade dog food. This concept is based on the idea that the body, ours and dogs, can “catch up” or store nutrients that may be missing in the diet. Variety will provide one day what nutrients may have been missing other days. Over time it is thought that all will even out and provide adequate nutrition. Although this may be true for some nutrients, like oil soluble vitamins and some minerals, it is not true for others.
Water Soluble Vitamins
The 12 “B” vitamins and vitamin C are water soluble. This means that they cannot be stored in the body. What is not used by the body’s cells will be flushed away in the urine. The B vitamins need to be supplied daily in their necessary amounts. So what happens if certain B vitamins are missing from the diet?
Vitamins help chemical reactions in the cells. If they are not available the chemical reactions do not occur. This means certain chemicals will not get made until the necessary B vitamin is available. The body suffers a shortage until variety in the diet restores the missing B.
Whether the body catches up and restores the entire amount lost is dependent on the amount of the necessary B vitamin present in the diet. Since all foods have different quantities of the B vitamins, simply offering a variety may not make up the loss. Statistics does not guarantee a “reversion to the mean” and everything will even out. This can have serious consequences depending on the importance of the particular chemical to the body.
Calcium, Phosphorus and Magnesium
Calcium, phosphorus and magnesium are the primary minerals in bone. Bone can be viewed as a storage source for these minerals. In times of shortages of these minerals, the body will dissolve bone to maintain constant blood levels. This is extremely important for calcium blood levels to maintain proper heart and nerve function.
The body will continue to dissolve bone until the minerals are replaced in the diet. Whether the amount of bone lost during shortages will be replaced is dependent on the diet. Most homemade dog diets without calcium supplementation have inadequate calcium despite the variety of green vegetables and dairy products. Even those that add raw bones may not provide adequate calcium. In fact, veterinarians are beginning to see more cases of osteoporosis and osteomalacia (inadequate bone development in puppies), diseases that we have not seen in decades.
Variety Does Not = Balanced
The diet of wild ancestral dogs had variety. They ate meat when they could catch it or find it dead. They ate insects, plants, fruits and grasses. They even ate poop for nutrients it may have provided. Yes, they had variety. They also had short lives. Malnutrition played a big role. Their bodies did not seem to “catch up.” Variety will not guarantee a balanced diet. Homemade diets for dogs have to be specifically formulated and carefully supplemented. Food alone, no matter how varied, will not provide balanced nutrition.
~Dr Ken Tudor
THE DOG DIETITIAN