As I teach, I learn. In October, I was updating my lecture on holistic diets for cats and dogs for my course, “Critical Overview of Complementary and Alternative Medicine.” In this talk, I speak about the plusses and pitfalls of various veterinary diets, such as raw meat, home-cooked, Chinese veterinary food therapy and more. But the pros, cons, benefits, and risks of going natural versus mainstream used to be clearer.
That distinction disappeared for me this year. The seemingly endless recalls of commercially prepared pet foods both “natural” and “not so natural” (i.e., those touted “holistic” and others more traditional), made me realize that we still have serious problems with pet food, three years after the melamine tragedy. No matter what the label claims as to its health benefits, the food can still be tainted, or the vitamins in the package present in excess or deficient amounts.
This past October, Vitamin D toxicity in “all natural,” “healthy,” and “holistic” dog food led to canine health problems across the country. In June, 2010, Iams recalled ProActive Health Cat and Kitten Food due to insufficient levels of vitamin B1, or thiamine. Thiamine deficiency, as I discuss later, can lead to serious neurologic impairment and weight loss.
No wonder we’re scared.
Then, there’s the veterinary dogma about not feeding table scraps. I cringe when I hear colleagues insist that the foods their clinic sells constitute the only safe options. I have further unease with their insistence that providing freshly prepared “human” food is sinful and detrimental. I refuse to regard my clients as incapable of setting limits on the types and amount of food they feed their dog or cat from the dinner table. I resent the paternalistic stance and belief that, left any latitude, clients will cause their companion pancreatitis or obesity. Doctoring includes teaching, and with that comes dialogue and assessment of caregivers’ capacity to follow instructions and guidelines. Some of my most-well educated clients prefer to feed their dog from a bag or can. That’s OK; I do as well. But I’m not against adding medically appropriate human food in reasonable quantities. At least when consumers cook their own food for a canine companion, they can track its source and freshness to a greater degree than the unidentifiable mixture contained in a can or bag.
In fact, if human-grade food is so detrimental, and a diversity of foodstuffs so dangerous, why is a mainstream manufacturer now advertising their “natural” diet, replete with whole grains, fruits, and veggies? I’m accustomed to seeing this panoply on “holistic” labels, but not an industry giant’s.
Home cooking offers the benefits of selecting high-quality meats and vegetables while destroying organisms that might otherwise pollute our households. Home-prepared meals, however, usually require supplementation in order to compensate for potentially missing nutrients. On the other hand, hypervitaminosis (i.e., vitamins in excess) is not good, either. Both can cause serious metabolic, orthopedic and neurologic problems.
Nutrient needs vary with species and state of health. Not all vitamins essential for humans are needed by other species. For example, aside from primates, guinea pigs and some fish, vitamin C is not essential to add into the diet for most other species, as they can make their own. However, animals facing certain disease states may require additional vitamin C, rendering the nutrient “conditionally essential.” Physiologic changes during illness, pregnancy, or lactation alter requirements. Anyone considering home-prepared meals for their dog or cat should work in conjunction with their veterinarian and/or a board-certified veterinary nutritionist to ensure that the foods meet muster.
Becoming acquainted with the signs of vitamin deficiency and excess can help us identify contributors to chronic ailments in our companions. We can then “consider the source” of vitamins and then add foods rich in daily requirements that might otherwise be missing from the diet.
Vitamin A
What It Does: Vitamin A provides chemical components necessary for vision, reproduction, and normal development of skin, bone, and muscle. Pregnancy and lactation increase vitamin A needs.
Sources: Vitamin A levels vary in foods; processing and storage can destroy it. Liver, fish oil, egg, and dairy products contain high amounts of pre-formed vitamin A. While dogs can transform beta-carotene from vegetable sources into vitamin A, cats cannot. As such, they require it pre-formed, from animal sources.
Deficiency: Prolonged deficiency of vitamin A causes dry eye, night blindness, retinal degeneration, weight loss, poor skin and hair coat, kidney and reproductive problems, bone changes, and immune deficiency. A recent report linked vitamin A deficiency to epilepsy in calves.
Toxicity: Cats fed home-made diets of raw pork liver may develop hypervitaminosis A, or vitamin A toxicity. The bones in their neck and elsewhere deform or fracture, compressing nerves and the spinal cord. They experience neck pain and loose teeth. Hypervitaminosis A can also cause appetite depression, skin thickening, internal bleeding, conjunctivitis, and impaired liver and kidney function. (more…)