nutritional disorders
Overview of Nutrition
Fats
Fats are broken down into fatty acids and glycerol. Fats are required for tissue growth and hormone production. Saturated fatty acids, common in animal fats, tend to be solid at room temperature. Except for palm and coconut oils, fats derived from plants tend to be liquid at room temperature; these fats contain high levels of monounsaturated fatty acids or polyunsaturated fatty acids (PUFAs). Partial hydrogenation of unsaturated fatty acids (as occurs during food manufacturing) produces trans fatty acids, which are solid or semisolid at room temperature. Until recently, in the US, the main dietary source of trans fatty acids was partially hydrogenated vegetable oils, used in manufacturing certain foods (eg, cookies, crackers, chips) to prolong shelf-life. However, in 2015, the U.S. Food and Drug Administration (FDA) removed partially hydrogenated oils from its Generally Recognized as Safe category based on extensive research that showed that trans fatty acids elevate LDL cholesterol, lower HDL cholesterol, and increase the risk of Overview of Coronary Artery Disease . Since June 2018, artificial trans fats have been banned in the US. Essential Fatty Acid Deficiency (EFAs) are Linoleic acid, an omega-6 (n-6) fatty acid Linolenic acid, an omega-3 (n-3) fatty acid Other omega-6 acids (eg, arachidonic acid) and other omega-3 fatty acids (eg, eicosapentaenoic acid, docosahexaenoic acid) are required by the body but can be synthesized from EFAs. EFAs are needed for the formation of various eicosanoids (biologically active lipids), including prostaglandins, thromboxanes, prostacyclins, and leukotrienes. Consumption of omega-3 fatty acids may decrease the risk of coronary artery disease. Requirements for EFAs vary by age. The adequate intake for alpha-linolenic acid is 1.6 g/day for men and 1.1 g/day for women. The adequate intake for linoleic acid is 17 g/day for men and 12 g/day for women between 19 and 50 years of age. (Adequate intake is defined as the average nutrient intake consumed daily by a population of healthy people.) Vegetable oils provide linoleic acid and linolenic acid. Oils made from safflower, sunflower, corn, soy, primrose, pumpkin, and wheat germ provide large amounts of linoleic acid. Marine fish oils and oils made from flaxseeds, pumpkin, soy, and canola provide large amounts of linolenic acid. Marine fish oils also provide some other omega-3 fatty acids in large amounts. The recommended intakes of EFAs can be met with 2 to 3 tablespoons of vegetable fat daily or by consuming about 3 to 3.5 ounces of cooked fatty fish such as salmon twice a week. 