When you mention peas, most people probably think of English garden peas – those tasty little peas that come from pods. Cooked with a little butter on the stove, they are delicious. Added to some chicken or stew, your dog will love them. If you give them to your dog occasionally, there’s no harm. They have more protein than you probably expect. Plus, they are low in fat and they provide some fiber. They also contain vitamins and minerals that are good for your dog, including Vitamin K.
However (there’s often a “however” with foods for dogs), other peas and some related ingredients have been used in large amounts in grain free dog foods in recent years. There are now serious concerns about grain free dogs foods with these ingredients, including various kinds of peas.
When Peas Aren’t Good for Your Dog
In July 2018, the U.S. Food and Drug Administration (FDA) put out a warning saying that they were investigating a potential link between dog foods containing peas, legumes, lentils, and potatoes (including sweet potatoes) and dilated cardiomyopathy (DCM) in dogs. These ingredients are often the major ingredients in grain free dog foods. Dilated cardiomyopathy is a serious, often fatal heart disease in dogs that involves the enlargement of the heart. Researchers at UC Davis are also working on the case, along with veterinary cardiologists at other universities.
There are genetic forms of dilated cardiomyopathy but this is believed to be a diet-related form. In recent years, more and more veterinarians have been reporting cases of DCM in dogs of various breeds, mixes, and sizes. When researchers began investigating, especially at the University of California-Davis, they began to see a pattern. An unusually high number of affected dogs were eating grain free diets. The diets all appeared to share common ingredients such as peas, lentils, legumes, and potatoes.
The exact reasons why some of these ingredients might be causing DCM in dogs is not yet known. However, some dogs that have been eating grain free dog foods are testing very low for the amino acid taurine. If you’re not familiar with taurine, don’t feel bad. It’s not something that dog owners usually worry about since most dogs make it in their bodies, as long as they are eating a good diet. Taurine is important for normal vision, good digestion, normal heart muscle function, and to maintain a healthy pregnancy and fetal development. It also helps support a healthy immune system.
Cat owners are probably more familiar with taurine. Back in the 1980s, thousands of cats became blind and/or died because of a lack of taurine in their cat food. Cats cannot make their own taurine, as pet food manufacturers discovered, so it has to be added to their food, usually in synthetic form.
Taurine naturally comes from animal products, especially meat and fish. While many grain free dog foods can appear to have high protein percentages, much of the protein usually comes from plant sources such as peas, other legumes, and lentils. This plant material has virtually no taurine. Even so, this may not be the cause of the taurine deficiency in grain free dog foods.
Researchers are still investigating why ingredients such as peas, legumes, lentils, and potatoes (including sweet potatoes) could be involved with low taurine levels. One theory is that these ingredients could be inhibiting or blocking the dog’s body from absorbing taurine. If that’s the case, then as long as you continue to feed a dog food that contains these ingredients, it doesn’t matter how much meat or fish protein your dog eats. It wouldn’t matter if you supplemented your dog’s diet with extra taurine. These ingredients could be blocking your dog from getting the taurine he needs in his diet.
Some grain free pet food brands have been rushing to add synthetic taurine to their foods. However, until researchers pinpoint the problem, these foods have to remain suspect. In case you are wondering, the foods involved include many of the bestselling and most expensive grain free dog foods on the market today so it’s not a question of inferior or cheap dog foods.
There are other theories but we simply don’t have answers right now. At this time most of the focus is on the idea that peas, legumes, lentils, and root vegetables such as potatoes and sweet potatoes are somehow blocking the absorption of taurine. Even adding more taurine to a dog’s diet with toppers like eggs or sardines doesn’t seem to raise the dog’s taurine level or prevent DCM if the dog is eating a grain free diet with ingredients that can inhibit taurine absorption.
What Can You Do?
According to the cardiac veterinarians involved in researching the problem, much of the trouble likely stems from grain free dog food makers that have not used professional veterinary nutritionists to formulate their dog foods. They recommend feeding foods that have research to back up their formulas; that have qualified veterinary nutritionists formulating their foods and rigorous quality control; and that can give you a complete nutrient analysis (not a guaranteed analysis) of their foods. They also discourage the use of exotic ingredients because they are hard to work with and can lead to nutritional deficiencies You can find out more about what to look for in a good dog food here.
Many dogs do not show any symptoms of DCM until they are very sick. For many owners, a cough and weakness are the first signs they notice in their dogs. Other symptoms can include difficulty breathing, an increased heart rate, fainting, and pale gums.
According to the FDA, if you have been feeding a grain fee dog food and your dog is showing possible signs of DCM, you should contact your veterinarian. Your veterinarian can often recognize early heart disease by hearing a heart murmur or abnormal heart rhythms. If you observe these things or your veterinarian is concerned, additional testing may be indicated such as x-rays, blood tests, EKG, or heart ultrasound (echocardiogram). Your veterinarian may ask you for a thorough dietary history, including all the foods (including treats) the dog has eaten.
You can have your dog’s taurine level tested if you are concerned. If you plan to have your dog’s taurine level tested, it’s best to test before you make any dietary changes in order to get an accurate reading.
If your dog is diagnosed with DCM:
- Ask your veterinarian to test blood taurine levels.
- It’s important to report test results, including the food you have been feeding, to the FDA.
- Change your dog’s diet as directed by your veterinarian’s recommendations.
- Ask your veterinarian to help you identify a dose for taurine supplementation.
- Seek guidance from a veterinary cardiologist.
- Follow the instructions from your veterinarian or veterinary cardiologist as repeat evaluations and other medications may be needed. It can take several months to see improvement in many cases of diet-related DCM.
Some dogs diagnosed with diet-related DCM have recovered with treatment and a change in diet but it depends on many factors.
If you are thinking of changing your dog food, Dr. Stern at UC Davis offers some advice. He recommends that you choose a food that does not contain any of the suspect ingredients among the first five ingredients listed. The FDA recommends that you don’t feed a food that uses any of the suspect ingredients before the vitamins and minerals are listed.
Small sprinklings of peas added to your dog’s regular food won’t hurt him if you feed them occasionally. On the other hand, many grain free pet food companies have used large amounts of peas, lentils, legumes, potatoes, and sweet potatoes in their foods. According to the FDA, there appears to be a connection between these ingredients and an increase in dilated cardiomyopathy in dogs. If you have concerns about your dog, talk to your veterinarian. Have your dog tested if you are worried.