Presently, human nutrition information is buzzing about the health benefits of various types of oil. Entire diets or dietary supplements are focused these fatty acids.
Olive oil, the cornerstone of the Mediterranean diet, has long been recommended by doctors for reducing the risk of heart disease. It is believed that this monounsaturated fat lowers total blood cholesterol and decreases the “bad” cholesterol LDL (low-density lipoprotein). Less LDL is thought to play a major role in the formation of plagues that clog heart arteries.
Coconut, flaxseed and safflower oils have also shown to have positive effects on blood cholesterol in humans.
Olive and flaxseed oils also contain omega-3 fatty acids. Omega-3 fats have anti-inflammatory effects and aid in skin and fur quality
So are these wonderful fats good for homemade dog food? As primary sources of dietary fat, the answer is no.
Dogs’ Hearts Are Different
Fortunately dogs do not suffer the cardiac risk that we humans do. Heart problems as a result of heart artery blockage do not exist for the dog and blood triglyceride and cholesterol levels offer no cardiac risks. So it is unnecessary to use these more expensive oils.
Dogs do need specific daily amounts of omega-3 and omega-6 fatty acids. Specifically, they need an omega-6 fat called linoleic acid and an omega-3 called alpha- linlolenic acid. So why wouldn’t olive, flaxseed or safflower oil be good choices?
All Oils Are Not Created Equal
The omega-3 and omega-6 fats in cottonseed, palm, peanut, olive, flaxseed, safflower, sesame, sunflower and walnut oils are undifferentiated omega’s. This means the body has to convert undifferentiated fat to linoleic and alpha-linolenic acid. In humans, dogs and cats fatty acid conversion is extremely variable. Sex, age and health status can all affect the conversion efficiency of undifferentiated fats.
The amount of linoleic or linolenic acid that is converted from dietary undifferentiated omega-3’s or omega-6’s is only a guess. It is impossible to know if any particular dog eating undifferentiated fats is getting adequate levels of linoleic or linolenic acid unless special blood tests are performed.
This is especially true of the omega-3 fatty acids known as DHA and EPA. These special fats have a powerful anti-inflammatory effect and are helpful in treating allergies and other related inflammatory conditions as well as some types of cancer. They are also important for skin and fur health.
EPA can be converted from the undifferentiated fat in the above oils. But it is dose dependent meaning higher amounts of undifferentiated fats are needed to increase the blood levels of EPA. Increasing the dietary fat to achieve optimum levels of EPA increases the fat calories in the diet. This is not always desirable.
DHA is not converted from the undifferentiated fats in these oils. Instead an intermediate form of the acid called DPA is produced. DPA is converted to DHA in the retina of the eye and the brain. The efficiency of this conversion is completely unknown. It is also not clear how or if the DHA in the nervous system is released back into the blood to aid in the immune system or skin and fur health.
Ideally linoleic and linolenic acid should be present in a preformed state in the diet. This way there is no need of conversion and the precise amount of these acids in the diet is knowable.Contrary to all of the health claims about coconut oil, it contains no omega-3 essential fatty acids and microscopic amounts of undifferentiated linoleic acid. This makes coconut oil unsafe as the sole source of essential fatty acids in homemade dog food diets.
Corn, Canola, Soybean and Fish Oil
Corn oil is the richest source of preformed linoleic acid. Canola and soybean oils are the best sources of preformed alpha-linolenic and linoleic acids. These qualities make it possible to meet the dog’s daily requirement for linoleic and linolenic acids without adding excessive fat to the diet.
Only 1/2 teaspoon of corn oil per 10lbs. of body weight per day provides the necessary amounts of linoleic acid. 1 teaspoon of canola oil or 1/2 teaspoon of soybean oil per 10lbs. of body weight will provide the neccessary amounts of both linoleic and alpha-linolenic necessary in the daily diet. Corn, canola and soybean oils are less expensive than other oils so they help reduce the cost of homemade dog food.
Fish body oil is the richest source for both preformed EPA and DHA. Krill oil is a less concentrated source of DHA and EPA and is more expensive. Although rich in preformed DHA, oils from sea algae do not contain EPA. 33mg of combined DHA and EPA per 10lbs. of body weight will meet a dog’s daily requirement of these essential fats. For skin and immune health doses 3-10 times that dose are considered safe. When supplementing with any oil always remember each teaspoon of any oil adds 40 calories to the diet. So you need to make the necessary adjustments in calorie intake.
Although using oils that are considered healthy for humans is tempting to use in homemade dog food, they are not that healthy for dogs. There is no guarantee that their use will provide the daily requirements of essential fats discussed in this post.
Corn, canola, fish body and soybean oils provide exact amounts of preformed essential fats. They are also less expensive than other oil sources. These qualities make them perfect for homemade dog food.
Dr. Ken Tudor,
THE DOG DIETITIAN