On January 1, 1998, AAFCO began allowing omega-3 and omega-6 fatty acid information on pet food bags.
This article is not intended to be a primer on fatty acids. You just got that in the last article. My goal here is to answer a simple question: How much omega-3 is enough? And how much omega-6 is too much for your dog?
Let’s get some definitions out of the way first. Fatty acids are fats, but with a certain chemical structure. Linoleic acid is the one fatty acid that is essential in a dog’s diet – the dog doesn’t make its own. Linoleic acid is an omega-6.
All fatty acids are chains of carbon atoms with oxygen atoms hooked on at one end (the alpha end), and three hydrogen atoms hooked on at the other end (the omega end). They differ based on how many carbon atoms are strung together, and where there are double bonds instead of single bonds between the carbon atoms. Omega-3 fatty acids have the first double bond three carbon atoms away from the omega end. Omega-6 fatty acids have that bond six carbon atoms from the omega end. Omega-6 fatty acids used to be called polyunsaturated fats. They have three or more double bonds.
Omega-3 corrects many dry skin problems and has been reported to decrease arthritic stiffness. People have reported that it gives them and their dogs more energy. Omega-3 comes from fish, flax and animals who have lived on grass and leaves.
Omega-6 fatty acids come from corn and animals who have lived mostly on corn. According to a new book, The Omega Plan by Artemis Simopoulus, M.D., in the last 100 years, the supply of omega-3 in humans’ and pets’ diets has decreased 80%, whereas the omega-6 supply has increased 300%. She’s found that eating a balanced diet, including the right fats, is the key to good health and longevity for animals and humans. Getting enough omega-3 fats is key, she says.
Omega-3 and omega-6 compete with each other in the metabolic machinery of mammals. Excess levels of omega-6 lead to inflammation-type diseases: arthritis, cancer, heart trouble, atopy (itching) and many other degenerative diseases.
So, what are the optimal levels of omega-6 and omega-3?
Most of the answers we have today are based on experiments with rats. How-ever, most laboratory rats don’t live long enough to develop degenerative diseases. Therefore, we have to look to the long-living human population to find the best answers about the ideal ratio of omega-6 to omega-3.
According to Dr. William Lands, the leading omega-3 and omega-6 researcher in the U.S., the ideal level of omega-6 (based on the longest-living, healthiest people on earth) is 1% of the diet (by weight of the diet). That works out to 5 grams of omega-6 per pound of dog food. This happens to be the same level AAFCO started recommending several years ago.
Based on Land’s studies and most other fatty acid research with monkeys, rats, mice and people, 1% is enough and not too much omega-6 for all mammals. Nearly all the studies show that higher levels of omega-6 lead to a greasy coat and higher risk for cancer, arthritis and inflammatory diseases of all types.
Because the body uses the same pathways to metabolize both omega-6 and omega-3 fatty acids, finding the ideal ratio of the two types of fatty acids is important. Since too much omega-6 inhibits the metabolism of omega-3, the search is on for the right balance. Based on research with dogs, Iams Company researcher Dr. Greg Reinhart recommends a ratio of omega-6 to omega-3 ranging between 5 to 1 and 10 to 1. Researcher Doug Bibus of the University of Minnesota recently completed a study with dogs. He suggests a lower ratio: between 2 to 1 and 4 to 1.
If you use the 5 to 1 ratio as a middle value, this means that a dog food that contains 1% omega-6 (also called Linoleic acid) should contain 0.2% of omega-3 (also called Linolenic acid). Looking at all of the acceptable ratios, you should find somewhere between 2 and 10 times as much omega-6 as omega-3 in the food.
Most Super-Premium pet foods have about 2% to 3% of omega-6 and thus should contain 0.4% to 0.6% of omega-3.
Very few labels will tell you the exact level of omega-6 and omega-3 fatty acids. You may have to call and ask the manufacturer. Some companies checked by Good Dog! didn’t have the data available (shame!). That means you have to guess.
You can estimate the fatty acid content by looking at total fat and omega-6 (linoleic) content. If the dominating ingredients are corn or corn germ and poultry fat or vegetable oil, you can be sure that the dog food contains mostly omega-6. Corn oil has a 60 to 1 ratio of omega-6 to ome-ga-3, poultry fat has a 20 to 1 ratio. Those foods need to be balanced out. You can add about 1 tablespoon of stabilized flax or 1 teaspoon of fish oil to each pound of dog food. If you see flax, fish meal or fish oil as ingredients, odds are the manufacturer has taken the time to balance the ratio. (Note that many dogs don’t like fish.)
Beware of lipid (fat) supplements, too – many of them are loaded with ome-ga-6 and not very much omega-3. Better to stick with whole ground flax seed or fresh fish or fish oil.
ENRECO, Inc. is the leading manufacturer of flax products for pet foods and human foods. They’re also affiliated with a bakery which ships flax bread and other products everywhere. Call 800-962-9536 for details.