Confusion Around Diets for Healthy Skin and Coat

By Jennifer Coates, DVM on Jun. 19, 2015

Owners often look to a dog’s diet as the cause and/or solution to skin and coat problems. While this approach is sometimes valid, pet food manufacturers tend to overemphasize this link. A recent study evaluated the “marketing terms, ingredients, and nutrient profiles of OTC [over-the-counter] diets marketed for skin and coat health of dogs to gain a better understanding of common marketing strategies and identify patterns of ingredients and nutrient concentrations.”

Eleven brands consisting of 15 dry and 9 canned diets marketed for skin and coat health were included in the study. The authors found:

Although all 24 diets had the term skin, coat, or other descriptors of skin and coat appearance in the diet name, a variety of other marketing terms were also included on the diet packaging and websites.

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The researchers also looked at the number and type of ingredients included in the diets, since over-the-counter limited diets or novel ingredient diets (e.g., lamb, kangaroo) are often marketed for the management of food allergies in dogs. They found:

Median number of unique major ingredients in each diet was 5.5 (range, 3 to 8), with a median of 2 animal-based ingredients (range, 0 to 5) and 3 plant-based ingredients (range, 1 to 5). Median total number of unique ingredients in each diet was 38 (range, 28 to 68). The most common animal-based ingredients were fish (n = 11), egg (7), and chicken (6), with smaller numbers of other animal-based ingredients (venison [4], dairy [3], animal digest [2], duck [2], lamb [2], turkey [2], beef [1], and pork [1]). The most common plant-based ingredients were rice (n = 17), potato (12), oat (11), pea (10), and barley (9), with smaller numbers of other plant-based ingredients (sorghum [4], soy [4], millet [3], corn [2], quinoa [2], sweet potato [2], canola [1], lentil [1], tapioca [1], and wheat [1]).

Concentrations of nutrients associated with skin and coat condition also differed widely.

While this is not the most comprehensive paper I’ve ever read with regards to shortcomings of over-the-counter diets that claim to improve the health of dogs (they can’t legally claim to cure, treat, or prevent disease without being regulated like drugs), it does do a good job of reinforcing the old adage "buyer beware."

If your dog suffers from a disorder of the skin or coat and switching to a couple of different foods hasn’t helped, please make an appointment as soon a spossible with your veterinarian.