Topics » Nutrition Science » Essential Facts about Fats
T. Colin Campbell Center for Nutrition Studies

Separating fact from fantasy about this important subject!

Excess consumption of fat is one of the major causes of disease and premature death in modern societies. It is intimately associated with the current epidemic levels of cardiovascular disease, stroke, diabetes, and cancer of the breast, colon, and prostate. Though over-consumption of fats clearly presents us with serious health risks, certain types of fat are actually essential for maintaining optimum health. A health-promoting diet must contain an adequate quantity and quality of essential fatty acids, while still avoiding excess intake of fat.

Essential fatty acids

Fatty acids are one of the components that make up fat. Humans require some of these fatty acids, which are appropriately called essential fatty acids. They are considered “essential” because, unlike the other fatty acids which we can synthesize or “manufacture” in our bodies, the essential fatty acids must be obtained through our diet. There are two types of essential fatty acids, called the Omega-3 fatty acids and the Omega-6 fatty acids. The most common of the Omega-3 fatty acids consumed by humans is alpha linolenic acid. The most common of the Omega-6 fatty acids we consume is linoleic acid.

Essential fatty acids serve at least three important functions. They assist in the formation of cell membranes, in the transport and oxidation of cholesterol, and in specialized hormone production. According to some studies, at least 2-4% of total calories should come from dietary intake of Omega-6 fatty acids such as linoleic acid.

Whole natural foods

The best way to get your needed essential fatty acids is by eating a health-promoting diet derived exclusively from whole natural foods. The type of diet recommended by the National Health Association contains well over 5% of calories from linoleic acid (see chart). Essential fatty acids are found abundantly in green leafy vegetables, flaxseeds, soybeans, and nuts and seeds. Eating a health-promoting diet will provide adequate amounts of the essential fatty acids, without the problems associated with animal products, processed oils, and supplements, which are often promoted as sources for these essential nutrients. Walnuts, flax seeds and green vegetables including purslane are a rich source of the desirable Omega-3 fatty acids.

Conventional diet a problem

People eating the standard American diet, with its high concentration of processed foods, including oils, can actually develop essential fatty acid deficiency. There are several ways this can happen.

First, a diet containing large amounts of animal products, hydrogenated vegetable oils (the synthetic fats found in margarine), and other foods low in essential fatty acids can result in an overall dietary intake that is very low in essential fatty acids.

Second, the essential fatty acids in vegetable oils can be inactivated by common processing procedures, such as hydrogenation, which can interfere with the body’s ability to use them.

Finally, if you eat products containing these inactivated essential fatty acids, the chemistry of these products can disrupt your use of any active essential fatty acids. Therefore, if you eat processed products with inactivated essential fatty acids, you may actually develop an essential fatty acid deficiency, even if the remainder of your diet contains unprocessed, fully active essential fatty acids!

No alternative solutions

The fact that we need essential fatty acids does not mean that we need animal foods, oils, or expensive supplements. As John McDougall, M.D., author of The McDougall Program for a Healthy Heart, is fond of saying, “People love to hear good news about their bad habits.” So, it is not surprising that there is a seemingly endless introduction of fad diets and supplements into the marketplace, promising fantastic benefits to the purchaser wishing to avoid the bother of making meaningful dietary changes. Unfortunately, these products are no substitute for healthful eating.

There are significant health risks associated with deviating from a health-promoting diet. While animal products, including fish, contain essential fatty acids in their tissues, they also contain a biological concentration of mercury and other toxic metals in their flesh. The problems associated with this are well documented.

Likewise, scientific studies of expensive supplementation products containing essential fatty acids have consistently failed to substantiate the spectacular claims made for them by their producers. In addition, taking large amounts of essential fatty acids in supplement form can suppress the immune system, including the suppression of natural killer cells and the production of immune substances called cytokines. These immune functions are important for defending ourselves against viruses, bacteria, parasites, and cancer cells.

As for the health benefits attributed to diets high in olive oil, such as the Mediterranean diet, these benefits are likely due to the fact that this diet is nearly vegetarian. The positive epidemiological observations more likely occur in spite of the olive oil content, rather than because of it. In addition, the heating of all oil, including olive oil, can produce cancer-causing byproducts.

Healthful diet the key

It would be very convenient if health could be bought in a bottle. But health results from healthful living. The best way to get the essential fatty acids you need is by eating a health-promoting diet derived exclusively from whole natural foods.

Below: General dietary analysis of a one-week menu of health promoting recipes

Based on menus from The Health Promoting Cookbook, by Dr. Alan Goldhamer

This chart lists the average daily nutrient content of the recommended daily allowance for an average female 20 to 50 years old. Any specific individual may require more or less total food intake, depending on factors such as height, weight, age, and energy expenditure. This diet is derived exclusively from whole natural foods, including fresh fruits and vegetables, and the variable addition of raw nuts and seeds, whole grains, and legumes. It excludes all meat, fish, fowl, eggs, and dairy products, as well as added oil, salt, and sugar, and dietary drugs such as tea, coffee, alcohol, and tobacco.

Average daily nutrients from 2100-calorie menu

Nutrient Amount RDA% Nutrient Amount RDA%
Calories [1] [2] 2113 Kc 96% Vitamins    
Cholesterol 0 mg N/A Vitamin A 7867 RE 983%
Fat 37 gm N/A[3] Beta-Carotene 7073 pg N/A
Linoleic Fat 13.9 gm 284% Thiamin B1 3 mg 269%
Mono Fat 11.5 gm N/A Riboflavin B2 1.9 mg 146%
Poly Fat 15.7 gm N/A Niacin B3 23 mg 155%
Saturated Fat 5.4 gm N/A Pyridoxine B6 4.2 mg 260%
Protein 68 gm 135% Pant. Acid 9 mg 166%
Cystine 845 mg 199% Cobalamin B12 0 pg 0%[4]
Glutamic Acid 229 mg N/A Folate 934 pg 519%
Glycine 48 mg N/A Vitamin C 605 mg 1008%
Histidine 1394 mg 254% Vitamin E 25 mg 310%
Isoleucine 2494 mg 384% Vitamin K 1000 pg 1538%
Leucine 4259 mg 448% Minerals    
Lysine 2914 mg 364% Potassium 7906 mg 395%
Methionine 950 mg 223% Selenium .125 mg 227%
Phenylalanine 2620 mg 552% Sodium 531 mg N/A
Proline 84 mg N/A Zinc 12.8 mg 106%
Serine 51 mg N/A Calcium 856 mg 107%
Threonine 2133 mg 474% Chromium 0.22 mg 176%
Tryptophan 707 mg 283% Copper 3.8 mg 170%
Tyrosine 1804 mg 380% Iron 28 mg 187%
Valine 3084 mg 474% Magnesium 852 mg 304%
Carbohydrate 411 gm 149% Manganese 11 mg 309%
Fructose 36 gm N/A Molybdenum 167 pg 102%
Lactose 0 gm N/A Phosphorus 1905 mg 238%
Glucose 27 gm N/A Dietary Fiber 69 gm 315%
Sucrose 31 gm N/A Soluble Fiber 4.4 gm N/A
Alcohol 0 gm N/A Insoluble Fiber 16 gm N/A


  1. Percentage of calories: protein 12%, fat 15%, carbohydrates 73%
  2. Approximate weight of food consumed each day throughout the week is 3339gm.
  3. N/A = not applicable or no standard established
  4. Vitamin B12 (cobalamin) is produced only by bacteria. A strictly vegan diet (no animal foods) contains only trace amounts of vitamin B12 from bacterial contamination. Some vitamin B12 is produced by the bacteria in our mouth and intestinal tract, but it has not yet been proven that this is adequate for all people. To ensure that internal production and recycling of vitamin B12 is adequate, I recommend that vegetarians have a simple blood or urine test every one to three years for methylmalonic acid. This is the most sensitive indicator of vitamin B12 status. If the test for methylmalonic acid is positive, inclusion of vitamin B12 fortified foods or oral supplements can be undertaken. Pregnant and lactating mothers should ensure themselves of a reliable, vegetarian source of vitamin B12 in their diet, such as vitamin B12 fortified foods or oral supplementation.


Copyright 2024 Center for Nutrition Studies. All rights reserved.

Program Overview

  • 23,000+ students
  • 100% online, learn at your own pace
  • No prerequisites
  • Continuing education credits