Nutrients such as protein, fat, vitamins, and minerals are important players in the skin and coat health of dogs. To understand the role of these nutrients, it is necessary to start by understanding skin and hair.
The purpose of skin and hair is to block things from leaving (such as water or heat) or entering (such as viruses and bacteria) the body.
The hair coat is composed almost entirely of protein. If the animal's diet doesn't contain adequate protein quantity and quality, hair may fall out, or become dry, weak and brittle.
Skin is made up of squamous cells, flat cells tightly packed together. These cells have tough membranes that are composed of proteins and fats. Without proper amounts of these nutrients, cell membranes weaken, allowing water to escape and bacteria and viruses to enter more easily.
Proteins are found in both animal-based and plant-based ingredients. Animal-based proteins contain all the essential amino acids dogs need, whereas plant-based proteins may contain only some essential amino acids. Animal-based proteins help dogs achieve optimal health.
Fats can also be found in both animal-based and plant-based ingredients. They are incorporated into skin cells as fatty acids. There are two essential fatty acids for skin and coat health. Linoleic acid maintains skin and coat condition in dogs. Without enough linoleic acid dogs may experience dull, dry coat, hair loss, greasy skin and increased susceptibility to skin inflammation.
Both of these essential fatty acids are omega-6 fatty acids and are found in animal tissues like chicken fat. Linoleic acid is also found in some vegetable oils, such as corn and soybean oils.
Most commercial dog diets contain more than adequate amounts of omega-6 fatty acids. Because these fatty acids can be converted to compounds that increase susceptibility to skin inflammation, it is important to balance the amount of omega-6 fatty acids in the diet with omega-3 fatty acids, which reduce susceptibility to inflammation.
Omega-3 fatty acids are found in oils from fish and some plants (canola and flax).
IAMS research has found that combining fat sources in the diet at a ratio of 5-10 omega-6 fatty acids to 1 omega-3 fatty acid results in excellent skin and coat health.
Vitamins and minerals are essential for the development of healthy skin and hair coat. The best way to provide these nutrients is through a complete and balanced diet containing appropriate amounts of essential vitamins and minerals rather than through supplements.
| Vitamin or Mineral | Importance to Skin and Coat Health |
|---|---|
| Vitamin A | Necessary for growth and repair of skin |
| Vitamin E | Protects skin cells from oxidant damage |
| Biotin | Aids in the utilization of protein |
| Riboflavin (B2) | Necessary for fat and protein metabolism |
| Zinc | Necessary for fat and protein metabolism |
| Copper | Involved in tissue pigment and protein synthesis |
Diet is often believed to be a factor when changes in skin and coat condition are noticed. The most common causes of these changes, however, are season and life stage.
As cold weather approaches, most dogs grow a thick coat to help keep heat in and cold air out. As the weather begins to warm up, they shed the thick, heavy coat.
Most puppies are born with soft fuzzy hair, but as they age, a coarser coat grows. Pregnant or lactating dogs also may experience a change in coat condition or hair loss. And, as with humans, the hair on dogs may thin out and become coarser and white as they reach their senior years.
We’re not talking about the “Sit. Shake.” kind of shake. Nor the fun way they shake off water starting from their nose all the way to the end of their tail. (FYI, dogs can shake off 70% of the water on their fur in just four seconds!)
No, we’re talking about that full-body trembling you’ve likely seen your pooch do from time to time. Why do they do it? And is it something you should be worried about? Let’s shake a leg and find out.
A majority of dog owners in an IAMS™ survey* (64%) think dogs shake because they’re cold. Other top responses were because they’re scared (57%) or anxious (54%).
High-fives all around because it turns out there are a number of reasons dogs shake, and all those are possible correct answers.

Just like their owners, dogs will often shiver when cold.
Opens a new windowDr. Tammie King, Applied Behavior Technical Leader at Waltham Petcare Science Institute, says: “Dogs shiver in response to falling temperatures. Dogs with short or no hair are especially susceptible. You should get them warm, put coats on them or bring them inside.” Same goes for you.

“Shaking is a response to epinephrine or adrenaline secretion — a sign of anxiety where the dog is on high alert,” says
Opens a new windowJames Serpell, B.S., Ph.D., Professor of Humane Ethics & Animal Welfare at the University of Pennsylvania School of Veterinary Medicine. You may notice this when you’re at the vet or there’s a situation where they feel threatened. Dr. Serpell also offers a way to help in some cases: “Identify what’s triggering the behavior. Provide them comfort. Going forward, you can gradually desensitize your pet to the thing it’s afraid of.” Unless it’s clowns. Those are always scary.
Trembling can also be a sign of serious issues like injury, poisoning or kidney disease. Opens a new windowDr. Jo Gale, BVetMed CertLAS MRCVS, Senior Manager, Global Science Advocacy at Waltham Petcare Science Institute urges pet owners to be vigilant: “If a pet is unwell in another way, they could be trembling.” If their shaking is accompanied by symptoms like diarrhea, limping or vomiting, you should consult your vet straight away.
*Surveyed U.S. dog owners, age 18+
Sample Size: n=201
Fielded May 8-10, 2020