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A low-fat diet is usually used to help with weight loss or weight maintenance, and prevention and treatment of heart disease, high cholesterol, high blood pressure, cancer, and diabetes. Many low-fat diets are also vegetarian, although anyone can follow a low-fat diet, whether or not they are vegetarian. There are many different kinds of low-fat diets. The most general guidelines are to keep your fat intake at 20 to 30% of your daily calories, and saturated fat to 10% or less of your daily calories.Avoid sources of hidden fats by reading the nutrition facts panel on packaged foods to find out the total amount of fat per serving. Steer clear of highly processed low-fat or fat-free foods, which might have as many calories as the regular-fat version, and can lead to weight gain, even though they are labelled as “low fat.” Low-fat = lower on the food chain. Emphasise whole grains, fruits, and vegetables, and avoid higher fat dairy and meat products. See our articles on the Dean Ornish Diet and the Pritikin Diet Programme for more low-fat information.
What do the advocates say?
The American diet provides an average of 34% of total calories from fat, with 12% of total calories coming from saturated fat. The diet of many other countries is lower in fat content and this lower intake of fat appears to be associated with the lower rates of obesity and lower risks of a few diseases seen in those countries. The American Heart Association, The National Cancer Institute, the American Dietetic Association, and the USDA Dietary Guidelines for Americans of 2005 recommend that only 20 to 30% of our daily caloric intake should come from fat, with 10% or less coming from saturated fat. The American Heart Association also recommends that we consume 300 mg or less of cholesterol per day; this is a little more than the amount of cholesterol in one large egg, which is 213 to 220 mg. The average daily intake of dietary cholesterol is 220 to 260 mg for women and 360 mg for men.
Extremely low-fat, high-fibre, vegetarian diets—such as those developed by Max Warmbrand, ND, Nathan Pritikin, and Dean Ornish, MD—have been clinically proven to reverse coronary artery disease when combined with exercise and stress reduction; however, the effect of such a diet alone on coronary artery disease has not been systematically studied. Coronary artery disease is the leading cause of death and disability in the United States.
What do the critics say?
Not all fats are bad. Diets high in mono-unsaturated fats or omega-3 fatty acids are associated with lower risks of heart disease and other health problems. The body needs certain types of fat to function. An ultra-low-fat diet (providing less than 10% of calories from fat) may cause a deficiency of essential fatty acids (EFAs), which are essential for the structure and function of the body’s cell membranes and many other other important functions. Low-fat diets, especially when most animal products are avoided, may lack good sources of vitamins E and B12 and zinc. With too little fat in the diet, the body may not properly absorb fat-soluble nutrients, such as vitamin A, vitamin D, vitamin E, and vitamin K, and carotenoids, which are essential for the health of the eyes, skin, immune system, bones and teeth. In addition, some low-fat diets are also extremely low in calories, which could lead to further nutrient deficiencies and other problems if followed for a long time.
A low-fat diet is usually high in carbohydrates. Some critics contend that the high amount of carbohydrates in typical low-fat diets is unnatural for humans, who evolved for hundreds of thousands of years while eating a low-carbohydrate diet. They say that the current overconsumption of carbohydrates has led to increasing problems with obesity, diabetes, and other health problems. The consumption of high-carbohydrate diets is presumed to result in insulin resistance and related metabolic disorders such as high triglycerides, low HDL-cholesterol levels, and high blood pressure. However, not all carbohydrate sources contribute equally to these problems, especially those from whole unprocessed foods and/or those with a low glycaemic index.
What do I need to avoid?
Saturated fats: Found in red meat and dairy products, saturated fats raise blood cholesterol levels and increase the risk of heart disease. Avoid them by staying away from meats, whole milk products, butter, cream, and other dairy products that are not labelled “nonfat” or “fat-free.”
Polyunsaturated fats (PUFAs): These are found in vegetable oils such as corn oil, sunflower oil, and safflower oil. Although PUFAs lower cholesterol levels in most studies, the relationship between PUFAs and cardiovascular disease and cancer remains unclear. The same is not true with regard to fish oil and olive oil (which contains mono-unsaturated fat), both of which are associated with reduced risk of cardiovascular disease and may be associated with reduced risk of certain cancers. A more healthy alternative to PUFAs are mono-unsaturated fats, which are found in abundance in olive oil.
Trans fatty acids (TFAs): TFAs are found in processed foods containing partially hydrogenated oils, including many commercial snack foods, “vegetable shortenings,” and margarines. Partially hydrogenated oils are also used in deep-frying, so many fast foods, such as French fries, contain large amounts of TFAs. TFA consumption greatly increases the risk of heart attack. Avoid TFAs by eating as many whole, unrefined foods as possible.
Highly processed foods: Be aware that highly processed low-fat or fat-free products often have as many or more calories as the full-fat versions and should be avoided. Simply because a food is low-fat or fat-free, doesn’t mean that unlimited quantities can be consumed. An excess of calories—whether from fat-free or high-fat foods—will be converted to body fat, regardless of whether those calories come from fat or from sugar (carbohydrate).
Bread, cereal, rice, and pasta to avoid:
- Biscuits and muffins
- Doughnuts, pastries, and croissants
- Taco shells
- Popcorn with oil
Dairy products to avoid:
- Whole milk
- Creamed cottage cheese
- Cream cheese
- Butter
- Sour cream
- Single Cream
- Most cheeses (including part-skim and “lite” cheeses)
- Watch serving sizes: even “low-fat” and “1%” fat products can be significant sources of fat
Fats, oils, and sweets to avoid:
- Margarine
- Mayonnaise and salad dressings that aren’t low in fat
- All oils (however, olive oil and fish oil are healthy)
- Most cakes and pies
- Sweets bars
- Muesli bars
- Ice cream
- Chocolate
Note: Be aware that many “fat-free” or “reduced fat” foods contain high amounts of sugar (such as high fructose corn syrup) which is converted by the body into fat.
Protein (meat, poultry, fish, eggs, nuts, and beans) to avoid:
- Beef, pork, lamb
- Ham, sausages, hot dogs
- Chicken and turkey (with skin)
- Whole eggs
- Tuna (in oil)
- Tofu
- Peanut butter
- Nuts
Vegetables and Fruits to avoid:
- French fries, hash browns, and potato crisps
- Fried courgettes (or other fried vegetables)
- Avocados
- Coconuts
- Olives
Best bets
Bread, cereal, rice, and pasta:
- Bagels
- Pasta/noodles
- Soft corn tortillas
- Pita bread
- Corn bread
- Porridge
- Wheat germ
- Air-popped popcorn
Dairy products:
- Non-fat milk
- Non-fat yoghurt
- Other non-fat dairy products
Fats, oils, and sweets:
- Oil-free and some “lite” salad dressings
- Fat-free mayonnaise
- Non-fat frozen yoghurt
- Sorbet and fruit ices
- Fruit rolls and fig bars
Protein (meat, poultry, fish, eggs, nuts, and beans):
- Lean chicken and turkey (without skin)
- Egg whites
- Tuna (in water), halibut, bass
- Dried beans and peas
Vegetables and fruits:
- Raw, steamed, or boiled vegetables
- Raw fruits
- Vegetable and fruit juices diluted with water
Are there any groups or books associated with this diet?
American Heart Association 1615 Stemmons Freeway Dallas, TX 75207–8806 www.americanheart.org
American Dietetic Association 216 West Jackson Boulevard Chicago, IL 60606–6995 www.eatright.org
National Cancer Institute (NCI) Cancer Information Service 9000 Rockville Pike Building 31, Room 10 A-24 Bethesda, MD 20892 www.nci.nih.gov
Eat More, Weigh Less: Dr. Dean Ornish’s Advantage Ten Program for Losing Weight Safely While Eating Abundantly by Dean Ornish, MD, New York: Quill, 2001
Secrets of Fat-Free Greek Cooking by Elaine Gavalas, Garden City Park, NY: Avery Publ., 1999.
The National Cancer Institute of the National Institutes of Health Action Guide for Healthy Eating: Action List for Fat www.pueblo.gsa.gov/cic_text/food/guideeat/Alistpg.html
USDA’s MyPyramid: Steps to a Healthier You www.mypyramid.gov
Bibliography
Barnard RJ, Lattimore L, Holly RG, et al. Response of non-insulin-dependent diabetic patients to an intensive programme of diet and exercise. Diabetes Care 1982;5:370–4.
Barnard RJ, Martin DA, Ugianskis EJ, Inkeles SB. The role of diet and exercise in the management of hyperinsulinemia and associated atherosclerosis risk factors. Am J Cardiol 1992;69:440–4.
Brush MG, Watson, SJ, Horrobin, DF, Manku, MS. Abnormal essential fatty acid levels in plasma of women with premenstrual syndrome. Am J Obstet Gynecol 1984;150:363–6.
Gavalas E. Secrets of Fat-Free Greek Cooking. New York, NY: Penguin Putnam/Avery, 1998: 3–6.
Kretsch MJ, Sauberlich HE, Skala JH, Johnson HL. Vitamin B-6 requirement and status assessment: young women fed a depletion diet followed by a plant-or-animal protein diet with graded amounts of vitamin B-6. Am J Clin Nutr 1995;61:1091–101.
Martin W. Nathan Pritikin and atheroma. Med Hypotheses 1991;36:181–2.
Mattar JA, Salas CE, Bernstein DP, et al. Hemodynamic changes after an intensive short-term exercise and nutrition programme in hypertensive and obese patients with and without coronary artery disease. Arq Bras Cardiol 1990;54:307–12.
The National Cancer Institute of The National Institutes of Health. Action Guide for Healthy Eating: Action List for Fat. 1999 (Online) www.pueblo.gsa.gov/cic_text/food/guideeat/Alistpg.html
Ornish D, Brown SE, Scherwitz LW, et al. Can lifestyle changes reverse coronary heart disease? The Lifestyle Heart Trial. Lancet 1990;336:129–33.
Ornish D, Denke M. Dietary treatment of hyperlipidaemia. J Cardiovasc Risk 1994;1:283–6.
Ornish, D. Eat More, Weight Less. New York, NY: Harper, 1993.
Ornish D, Scherwitz LW, Billings JH, et al. Intensive lifestyle changes for reversal of coronary heart disease. JAMA 1998;2800:2001–7.
Ornish D, Scherwitz LW, Doody RS, et al. Effects of stress management training and dietary changes in treatment of ischemic heart disease. JAMA 1983;249:54–9.
Rosenthal MB, Barnard RJ, Rose DP, et al. Effects of a high-complex-carbohydrate, low-fat, low-cholesterol diet on levels of serum lipids and estradiol. Am J Med 1985;78:23–7.
Sacks FM, Svetkey LP, Vollmer WM, et al. Effects on blood pressure of reduced dietary sodium and the Dietary Approaches to Stop Hypertension (DASH) diet. New Engl J Med 2001;344:3–10.
Schuler G, Hambrecht R, Schlierf G, et al. Regular physical exercise and low-fat diet. Effects on progression of coronary artery disease. Circulation 1992;86:1–11.
Slabber M, Barnard HC, Kuyl JM, et al. Effects of a low-insulin response, energy-restricted diet on weight loss and plasma insulin concentrations in hyperinsulinemic obese females. Am J Clin Nutr 1994;60:48–53.
The United States Department of Agriculture. USDA Dietary Guidelines for Americans, 2005. www.health.gov/dietaryguidelines/dga2005/document/pdf/DGA2005.pdf.; Accessed Feb 6 2007.
The United States Department of Agriculture. USDA coordinated nutrition research programme on health and nutrition effects of popular weight-loss diets. January 10, 2001. www.usda.gov/news/releases/2001/01/whitebac.htm
Watts GF, Lewis B, Brunt JN, et al. Effects on coronary artery disease of lipid-lowering diet, or diet plus cholestyramine, in the St. Thomas’ Artherosclerosis Regression Study (STARS). Lancet 1992;339:563–9.
Zavaroni I, Bonini L, Fantuzzi, M, et al. Hyperinsulinaemia, obesity, and syndrome X. J Int Med 1994;235:51–6.
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The information presented in the Food Guide is for informational purposes only and was created by a team of US–registered dietitians and food experts. Consult your doctor, practitioner, and/or chemist for any health problem and before using any supplements, making dietary changes, or before making any changes in prescribed medications. Information expires September 2008.
2007-09-01
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