vitamin A, vitamin E) from the gastrointestinal tract. Triglycerides constitute the major portion of the fats included in the diet. These are neutral fats, each consisting of three fatty acids attached to the trivalent alcohol glycerol. Among the more frequently encountered fatty acids are palmitic, stearic, oleic, and linoleic acids. While animal fats are predominantly saturated fatty acids (exception: salt water fish), vegetable oils have a higher content of unsaturated fatty acids (exception: coconut oil). Carbohydrates Carbohydrates are the preferred sources of energy of many organisms. The combinations most important in the human diet are the monosaccharides (e. g., glucose = dextrose), disaccharides (e. g., lactose = milk sugar), and polysacccharides (e. g., starch). Our diet contains chiefly monosaccharides contained especially in honey and fruit, disaccharides in milk and in all foods sweetened with the common household sugar saccharose (sucrose, cane sugar), and polysaccharides in vegetable (starch) and animal (glycogen) products. Carbohydrates can only be stored in small quantities in the body. For instance, during starvation the total store of glycogen in the liver and the skeletal muscles (about 300−400 g) is used up in a day and a half. Because of their sweet taste, simple sugars (monosaccharides and disaccharides) are very popular and have multiple uses. They are also suitable for protecting food from deterioration and therefore for preserving. On the other hand, simple sugars put a considerable burden on the pancreas. The small molecules
