Recommended Fat Intakes

An average person should have no more than 60 grams of fat in his or her daily diet. A certain package of chocolate chip cookies is labeled 1 portion is 3 cookies and also fat 6 grams per portion. How many cookies may one eat before exceeding 50% of one s recommended fat intake ... 

Voit (in 1880), Atwater (in 1895), and Rubner (1903) have recommended fat intake levels of 17, 32, and 16% of total energy, respectively. In the intervening 100 years, and particularly in the past four decades, the fat intake recommendations have slowly evolved from 32% (Atwater) to 16% (Voit and Rubner). On the other hand, the recommendation for EFA intake increased 4 to 5 times, from 1-2% to 4-10% of total energy intake. This change reflects revolution rather than evolution in lipid nuhition. 

The total amount of fat is the same in both examples because total fat is not restricted in FAOD, only the source of fat. Recommended fat intake for heeilthy Americans is 25-35 % of energy intake [2]. 

Digestion, Absorption, and Metabolism Functions Required Intake Recommended Fat Intake Essential Fatty Acids Polyunsaturated vs Saturated Sources... 

Also see CARBOHYDRATEjS], section on "Regulation of Fat Metabolism" FATS AND OTHER LIPIDS, section on "Recommended Fat Intake" and METABOLISM.)... 

The general recommendations on energy and fat intake are similar to those for the avoidance of heart disease. However, the recommendation to consume a variety of fruits and vegetables is based partly on the putative presence of diverse protective factors in plant foods. This concept does provide, at least in principle, a rationale for the functional health benefits of plant foods beyond the simple provision of nutrients at a level that prevents symptoms of deficiency. 

Most of our fat intake will consist of fatty acids with an even number of carbon atoms, but not all dietary fatty acids nor all those synthesized in the liver are saturated. A variable, but probably not inconsiderable, proportion of dietary fatty acids are unsaturated, partly perhaps because a high intake of unsaturated fat is recommended to help reduce the risk for diseases of the heart and vascular system. Unsaturated and odd-numbered fatty acids pose particular chemical problems to the 3-oxidation pathway and additional enzymes are required for their metabolism. 

In recent years breast cancer mortality has, if anything, shown a tendency to increase (40), indicating that current methods of treatment are having relatively little impact on this disease. The epidemiological data nevertheless show large differences in the mortality rates in different countries, which are strongly correlated with dietary fat in the food supplies. It is evident that new approaches are required to reduce the death toll from breast cancer in the more affluent countries of the world, and one way might be to reduce dietary fat intake as recently recommended by the NRC-NAS Committee on Diet, Nutrition and Cancer (14). 

The total fat intake must be reduced to achieve weight reduction by diet therapy.70 Dietary recommendations also include a reduction in saturated fatty acids. Drug therapy must be started only after confirmation of lipid levels such as cholesterol, triglycerides, LDL, and HDL. Adequate trial must be initiated with modification of dietary therapy, only failing which drug therapy must be started. 

Despite the logic of ketogenic diets for PDC deficiency on biochemical grounds, there are several theoretical concerns regarding their long-term use. For example, diets in which the fat intake is relatively low (<65%) may contain an amount of protein (to accommodate caloric needs) that exceeds the age-adjusted recommended dietary allowance. The acid load from such diets could exacerbate the congenital acid-base disorder in PDC-defective individuals and could contribute to the renal hyperfiltration reported to occur in some patients. Ketogenic diets may also cause hypercalciuria and increase the risk of bone demineralization in PDC deficiency. 

The National Cholesterol Education Program (NCEP)-recommended steps to lower the risk of CAD, collectively referred to as the TLC, are presented in Table 8.4. These guidelines are typically used for higher-risk individuals with elevated plasma cholesterol concentrations, established cardiovascular disease, and more than one major risk factor. The TLC dietary guidelines are relatively stringent, limiting daily total and saturated fat intakes to <30% and 7% of total energy and cholesterol... 

The current interest in dietary fat, however, stems primarily from its implication in the origin of several chronic diseases. Interest has centered on both the amount and type of dietary fat in the development of cardiovascular disease, cancer, hypertension, and obesity. As a result, dietary recommendations in many countries call for a reduction in total fat intake, to 30% of energy, and in saturated fat intake, to less than 10% of energy. In addition, some nutrition recommendations specify recommended levels of n-6 and n-3 fatty acids in the diets. Hence, the source of fat in the diet has assumed considerable importance over the past few years. Interest in the nutritional properties of canola oil developed because of its fatty acid composition (Table 2). Canola oil is characterized by a low level of saturated fatty acids, a relatively high level of monounsaturated fatty acids, and an appreciable amount of the n-3 fatty acid ot-linolenic acid (18 3 n-3). 

Excessive intake of any fat is not healthy. According to Klurfeld and Kritchevsky (342), the enhancement of tumor growth by dietary fat may result, in part, from the caloric contribution of this nutrient. Significant reduction of mmor incidence with consumption of 25% less energy was seen consistently in rat tumor systems induced by chemicals. Currently, most American children get about 34% of their calories from fat (318). It is recommended, however, that healthy children s intake of fat average no more than 30% of calories. Experts also suggest lowering children s saturated fat intake to less than 10% of calories. Similar recommendations have been made for adults (343). 

Absorption of dietary fat is a remarkably efficient process, so that in normal health, fecal fat is largely (if not entirely) derived from endogenous rather than dietary sources. Adequate dietary fat intake is therefore essential to minimize false-negative results. The BSG guidehnes recommend a diet containing at least 70 g fat for 6 days. In the UK only a minority of laboratories try to control (20%) or retrospectively assess (8%) fat intake. Patients with steatorrhea may reduce their fat intake to control their diarrhea and despite laboratory instructions may not increase their dietary fat... 

The American Heart Association recommends that all Americans lower their fat intake to 30 percent of their total daily calories. If you eat 2,000 calories a day, your fat intake should not exceed 600 calories.The average U.S. diet is 37 percent fat, and many go up to 40 or 50 percent. Dr. Dean Ornish and the late Nathan Pritikin advocated diets under 15 percent calories from fat to prevent or reverse cardiovascular disease. I recommend no more than 20 percent fat calories per day. 

Western diets typically contain low levels of n-3 PUFAs (Simopoulos, Leaf, Salem, 2000). Furthermore, relative to the diet of early man, today s diet is not only higher in saturated fats but has an altered ratio of the two major groups of PUFAs. Modern-day humans are, most probably, descendants of coastal-dwelling hunter-gatherers, with a primary diet of fish, shellfish, and plant matter. This omnivorous, and opportunistic, diet was varied and most probably low in saturated fat. The ratio of n-6 to n-3 fatty acids during the early part of human evolution was close to 1, whereas, today, the ratio is 10 1 or more (Eaton, Eaton, Sinclair, Cordain, Mann, 1998 Simopoulos, 1998). Arecent study in Australia (Sinclair, unpublished) indicates that DHA intake is 0.1 % of fat intake, or about 100 mg/d. The recommended intake is 0.5-1% (Simopoulos et al., 2000). Furthermore, recent data from our group (Sinclair, unpubUshed) has shown that reduced DHA levels in neural tissue occur in animals that are maintained on high saturated fat diets similar to that of a Western diet. 

The AI for men and women for fat is 1.6 and 1.1 g of a-linolenic acid daily, respectively, and for linoleic acid is 17 g/day for adult men and 12 g/day for adult women. Overall, fat should represent no more than 20% to 35% of total calories with the recommendation that saturated fatty acids, trans fatty acids, and dietary cholesterol intake be kept as low as possible while consuming a nutritionally adequate diet. As mentioned previously, fat intake in children less than 2 years of age is critical for proper central nervous system growth and development therefore, no fat restriction (e.g., skim milk) should be imposed until after the age of 2 years. 

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