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Taking action against dietary fats
By Joan Thompson, PhD, RD, CD
PPS Medical Advisor/Nutrition
This is the second instalment of The Prednisone Diet. Part 2: Getting Serious and Taking Action about Managing Dietary Fats
The management of dietary fats is of the utmost importance to a person who battles an inflammatory disease. As mentioned in the last issue, one of the most potent anti-inflammatory influences that can be made is to consume enough omega three fatty acids and to control the intake of omega six fatty acids. Now lets understand a more complete picture of dietary fats and provide some tips for consuming a healthy fat dietary composition.
Total dietary fat, is made up of saturated fats, monounsaturated fats and polyunsaturated fats. In the last issue, the category of polyunsaturated fats was introduced. As you recall, in the category of the polyunsaturated fats, there were two popular major categories mentioned; omega-three fatty acids (w3FA) and omega-six fatty acids (w6FA).
The W3FA are exceptional fats to consume. W3FAs are found in fish, flaxseed, walnuts, canola, primrose and borage oil. The problem with the dietary sources of W3FA is there is not an abundant amount of them present in the aforementioned good sources.
A person on a 2,000 calorie diet needs about five grams per day to have anti-inflammatory effect, and a person who consumes 3,000 calories per day requires about seven grams per day to blunt inflammatory events. One could consume this amount by eating seven ounces of sardines in oil, or nine ounces of mackerel, or 15 ounces of salmon per day.
Supplementing the diet with W3FA makes these dietary intake levels feasible. The typical American diet supplies less than one gram of W3FA per day. The three popular W3FA include alpha-linolenic acid (ALA), eicosapentaenoic (EPA) acid and docasahexaenioc acid (DHA). ALA comes in very small amounts from plant sources such as canola oil, walnuts, flaxseed, borage and primrose oil. EPA and DHA come from fish such as salmon, tuna, trout and herring. Supplementing with the fish oil (EPA and DHA) is more economical and effective than supplementing with ALA.
The other dominant polyunsaturated fat in the diet are the W6FA. The intake of these dietary fats is essential, but consuming too much W6FA do not support good health. W6FA are found in all plant oils, other than olive oil and canola oil.
The goal for a person with inflammatory disease regarding dietary fat management is to consume enough omega-three fatty acids in the diet to reduce the inflammatory response, but, not over-consume omega-six fatty acids. By not over-consuming the omega-six fatty acids, the production of inflammatory chemicals will be reduced. Adults require somewhere between 11 to 17 grams of linoleic acid per day. This can be provided by two to three tablespoons of a plant oil per day. By consuming a moderately-low-fat diet and maintaining a ratio of W3FA to W6FA that is 1:4 can be optimal.
How total fat intake is described is as a percent of total calories consumed. This means of all the calories eaten, what percent of those calories were provided from fat. The goal for dietary fat intake or acceptable macronutrient density range (AMDR) is 20-35% of Calories provided from fat. This means consume a low-fat to moderately low-fat diet.
A low-fat diet is defined as less than 25% of calories from fat, and a high-fat diet provides more than 35% of calories from fat. So again, by consuming a moderately-low-fat diet and maintaining a ratio of W3FA to W6FA that is 1:4 can be optimal.
There is another dietary fat that needs to be controlled as carefully as W6FA, and that is saturated fat. Saturated fats are abundant in high-fat animal products, tropical fats like coconut, palm and palm kernel fats, and hydrogenated fats, which are used commonly in, processed foods.
The recommendation for maintaining health is to consume saturated fat and W6FA at levels less than 10% of total Calories. This means for a 2,000-calorie diet that less than 20 grams per day should be consumed of each fat. The grams of saturated fat must be labeled in the Nutrition Facts Panel on food packages. So avoid high-fat animal products, tropical oils and hydrogenated fats.
The third type of dietary fat, and it is called monounsaturated fat. There are only four sources of dietary fats where the dominant type of fat is monounsaturated fat. Foods rich in monounsaturated fats include olive oil, canola oil, avocado and almonds. Monounsaturated fats are beneficial to human health. These sources of fats are recommended to be consumed in moderate amounts. They do not stimulate the inflammatory response in the body or promote chronic disease.
Here are the tips for reaching a healthy goal regarding fat intake:
1. Eat foods rich in W3FA such as salmon, tuna, trout, herring, mackerel, walnuts, canola oil, flaxseeds or green leafy vegetables.
2. Use monounsaturated oils such as canola and olive oils as your primary fat.
3. Avoid oils high in W6FA, such as safflower, cottonseed, sunflower, corn, soy and vegetable oils.
4. Reduce the intake of high-fat animal foods, tropical oils and hydrogenated fats; avoiding the use of vegetable shortenings, deep-fat fried foods; excessive intake of margarine, processed snack foods, and convenience foods.
Suggested reading:
1. Mahan, K & Escott-Stump, S (2004) Krauses Food, Nutrition & Diet Therapy, 11th Ed., Saunders; Philadelphia, PA.
2. Turley, Jennifer & Thompson, Joan (2004). Resources for Foundations in Nutrition: Power Tools, 3rd Ed., Thomson Learning; Bel-mont, CA. ISBN 0759342873.
3.Williams, Melvin. (2005). Nutrition for Health, Fitness and Sport, 7th Ed. McGraw-Hill Publishers; New York, New York.
