Only one claim is allowed on dog food. It has to do with improved oral hygiene because of a food’s positive impact on plaque and/or tartar control. (Look for a seal from the Veterinary Oral Health Council, or VOHC.) All other health claims on dog food packages are illegal. So how do manufacturers get away with such label claims as “the optimal blend of calcium, phosphorus, and essential vitamins to help maintain the bone health of mature dogs” and “guaranteed vitamin[s] help boost the immune response of senior dogs to that of healthy adult dogs”? Such claims are all over the pet food store.
The loophole is that such statements are not health claims per se but structure/function claims. It’s a legal distinction. A health claim links a food to a specific outcome down the line — feed this food and your dog’s mouth will be in better shape. But a structure/function claim amounts to nothing more than a statement that can be made for any food. It is not saying in any way that a food will prevent, cure, or treat a condition or disease. For example, what properly formulated food wouldn’t help maintain your dog’s bone health. And what dog food wouldn’t contain vitamins that in some way contribute to the maintenance of the immune system? If a manufacturer said a food could prevent osteoporosis or diseases that involve the immune system, such as cancer, it would be crossing the legal line. But insinuations — they pass the legal bar, misleading though they might be.