On a daily basis, we work with patients who avoid dietary fat because they believe the food myths that fats are bad for us, we can be healthier without fat, and eating fat makes us fat. For these reasons and more, many patients eat non-fat foods or follow a diet that severely restricts fat intake. These patients may be normal weight or overweight, but they all have an unhealthy relationship with fat, and are at higher risk for health problems, including diabetes, heart disease, and obesity.
We all should consume some portion of good fat in our diet. The total calories from healthy fat and the optimal percentage of dietary fat relative to carbohydrate and protein are highly individualized. The ideal amount depends on certain factors: your height, weight, age, health risk factors, medical conditions, exercise habits, food availability, food preferences, as well as your culture and genetics.
A healthy diet contains good (natural) fat from plant and animal sources. Natural fat is a combination of saturated, unsaturated and polyunsaturated fatty acid molecules (the building blocks of fat). Low- fat diets must be supervised by a healthcare provider. Non-fat foods have no place in a healthy diet. Natural fat with its combination of good fatty acids is a key nutrient for maintaining optimal health and a healthy weight.
Fatty acids have major roles in the body: as components of cell membranes, as precursors for certain hormones and vitamins, as a regulator of cholesterol in the bloodstream, and as stored fat for energy. Body fat stored as adipose tissue also functions to reduce inflammation, control appetite, and to regulate blood pressure and energy balance.
We recommend seasonal and regional varieties of natural fat from plant and animal sources because food consumed at the peak of freshness provides ideal nutrient value and flavor, and benefits the local economy and environment. We help patients choose a variety of good fats from fruit, vegetables, nuts, and seeds; olive oil and other cold-pressed or expeller pressed plant oils, whole grains; pasture raised chicken and eggs; grass-fed beef; wild-caught fish; dairy products from goat, sheep, and grass-fed cows.
It is worth noting that natural fat in meat and dairy products from ruminants like cows, sheep and goats contain small amounts of natural trans- fat. It is still good fat. Natural trans- fat does not have negative health effects when consumed as part of a healthy, balanced diet. Sources of natural trans- fat include meat from beef, goat and lamb, and dairy products such as butter, buttermilk, cheese, cottage cheese, cream, ghee, milk, sour cream, and yogurt.
There is only one bad fat: synthetic trans- fat, AKA: synthetic trans- fatty acids. Synthetic trans- fat causes health problems by sabotaging normal metabolism. Eating 2-3 grams of trans- fats daily increases the risk for a number of medical problems, including obesity, diabetes, heart disease, high total cholesterol, high LDL cholesterol, high triglycerides, low HDL cholesterol, breast and colon cancer, complications of pregnancy, disorders of infant development, and allergies. The New England Journal of Medicine reported in 2006 that eliminating industrial-produced trans- fats from the U.S. food supply could prevent between 6 and 19 percent of heart attacks and related deaths, or as much as 200,000 deaths each year.
Synthetic trans- fat is not formed in the typical household cooking processes of baking, frying and sautéing. For the sake of transparency, it is possible to produce some synthetic trans- fatty acids when using highly polyunsaturated oils in a deep fat pressure cooker fryer; this is the exception, not the rule. Synthetic trans- fat is primarily produced by industrial processes called hydrogenation and partial hydrogenation of vegetable oil to make solid fats like margarine and shortening. Synthetic trans- fat is also produced during industrial deodorization (refining) of canola, corn, palm, peanut, soybean, and sunflower oils. For example, canola oil is rich in linolenic acid, a type of omega-3 fatty acid. The industry refining target for trans- linolenic acid concentration in fully refined canola oil is less than 1.5% however; the percentage of trans- linolenic acid after deodorization can range from less than 1% to greater than 65%. Synthetic trans-fat is not present in unrefined oils or bleached oils.
Changes in labeling laws and the banning of synthetic trans- fat from restaurants in certain areas conceal but do not eliminate the presence of synthetic trans- fat. When the amount of synthetic trans- fat is below a threshold, the label reads “zero trans- fat.” But synthetic trans- fat is still present in foods made with deodorized, hydrogenated and partially hydrogenated vegetable oils. Case in point: Crisco® vegetable shortening ingredients include soybean oil (deodorized), fully hydrogenated palm oil, and partially hydrogenated palm and soybean oils. The front label of this product declares zero trans- fat per serving and the Nutrition Facts label on the back of the product states trans- fat zero grams. The only assurance you have that a product is trans- fatty acid-free is if the product clearly states “hydrogenated oil free” or “no hydrogenated oils.”
Processed foods and refined canola, corn, palm, peanut, soybean, and sunflower oils provide approximately 80% of all trans- fat consumed in the diet. Dietary sources of synthetic trans- fats include a rouges’ gallery of convenience foods and guilty pleasures, including: bread, breakfast cereal, cake, candy, canned biscuits and rolls, cookies, crackers, doughnuts, packaged frosting, margarine, nondairy creamer, frozen pizza crust, microwave popcorn, potato, corn and tortilla chips, premade foods prepared with deodorized vegetable oils, and shortening.
Nutritional advice is never “one size fits all” but a kernel of wisdom that benefits everyone is: Avoid synthetic trans- fat and eat a balanced diet containing natural fat in proportion to your dietary needs. If you or someone you know wants to have a healthy relationship with fat, a nutrition check-up is a great place to start.