There is a difference between a low fat and a low calorie diet and we'll discuss low calorie dog food in another article. While it's true that a lot of dogs in North America are overweight or obese (an estimated 40 to 60 percent, depending on the survey), low fat diets are usually provided when dogs have health conditions that make eating much fat problematic. Low calorie diets, on the other hand (or paw), are more often the choice if your dog needs to lose weight. There can be some overlap, but here we'll talk about feeding low fat dog food for health reasons.
What is low fat?
A low fat diet is usually considered to be one that has less than 10 percent fat by dry matter basis (less than 17 percent calories from fat). A diet with moderate fat is considered to be one that has between 10 and 15 percent fat by dry matter basis (17 to 23 percent fat from calories). And a high fat diet would be one that is more than 20 percent fat by dry matter basis.
As when figuring any nutrient in a pet food, it is important to subtract the moisture content so you can make comparisons on a dry matter basis. You can use a good online calculator for figuring dry matter basis for pet food nutrients, such as this one.
These are only rough estimates of the amount of fat in the food and how much your dog would be eating. You can go into more detail by reading the DogAware.com site. But these figures will give you enough to get started and make some useful comparisons. Many dog foods actually contain more fat than is listed on the label so in order to get accurate numbers for your calculations you will need to contact the pet food company and ask for them.
Which dogs need low fat diets?
Low fat diets are intended as adult maintenance diets for dogs who have chronic or acute attacks of pancreatitis that recur. Dogs who have exocrine pancreatic insufficiency (EPI) because of damage to their pancreas may also need a low fat diet. Dogs who have inflammatory bowel disease (IBD) can do well on a low fat diet in some cases. And some dogs require a low fat diet to control hyperlipidemia – high levels of triglycerides in the blood that can be a precursor to pancreatitis.
You might wish to try any dog who is having digestive problems on a low fat diet, on a temporary basis, to see if it helps. You can always discontinue the low fat diet if there is no improvement. Some dogs have an intolerance to fat or problems with malabsorption. These dogs can have symptoms such as weight loss and diarrhea. In some especially bad cases they can excrete excessive fat in the stool – called steatorrhea – producing stool which is large, greasy, pale, and stinky. Poor fat absorption can also be linked with gall bladder and liver disease, infection in the intestines, lymphangiectasia (a dilation of the lymph vessels that can result in a chronic form of protein-losing enteropathy); and other problems.
Dogs with any of these conditions can benefit from a low fat diet. However, this is not a hard and fast rule. Some dogs can return to a more normal diet once they are on the road to recovery. If a low fat diet isn't working for your dog, you can adjust the diet and increase the amount of fat to see if it helps.
It's also important to note that a low fat diet should not be fed to a pregnant or nursing dog or to a growing puppy. These dogs have greater nutritional needs and a low fat diet would be harmful for them. A low fat diet is only meant as a maintenance diet for adult dogs in certain situations.
Can a diet be too low fat?
Yes. Diets that are extremely low in fat are not usually recommended for dogs, even dogs with some of the conditions mentioned here. Diets that are too low in fat will probably not be nutritionally adequate in other ways for your dog, even if you add supplements to the diet. The National Research Council (NRC) which conducts research on dog nutrition does not recommend feeding dogs less than about 5 percent fat by dry matter basis, or less than 10 percent of calories from fat. That would be a very low fat food.
Keep in mind that some vitamins are fat-soluble. Without enough fat in the diet, your dog will not get enough of these vitamins. Skin, coat, and other organs can exhibit problems. Your dog can also feel hungry and lack energy without enough fat in the diet.
If your dog is having some of these dietary issues or gastrointestinal problems, you're probably already seeing your vet since problems like pancreatitis and other health issues are very noticeable – even life-threatening. If you're not, we suggest that you take your dog to see your vet about the health issues and you can work together on the diet.
There are some commercial dog foods that provide a low or moderately-low fat diet, but it's important to make sure that the food still has enough protein for your dog. Low fat and low protein combined are not recommended. There are also some low fat prescription diets available.
In some cases your dog might not like the taste of these foods. It's often the fat in a dog food that makes it taste good to dogs. If your dog doesn't like the taste of a low fat dog food you can try adding something to make it taste a little better such as cooked skinless chicken, a little boiled egg, or some cooked beef heart. If your dog will eat a little fruit, you can give him some slices of banana or some blueberries mixed in with his dog food. As long as he can eat these foods without problems, they should make his low fat dog food a little more appealing.