Nutrition Part IV: Fats

Author: Joseph Krachenfels

Fats like carbohydrates are composed of carbon, hydrogen, and oxygen; however, in fats these elements are connected together differently than in carbohydrates. “Fats can be found in plants and animals, and are insoluble in water” (Schwarzenegger 673). Fats provide 3 primary functions, “they are the major source of stored energy for the body, they serve to cushion and protect the major organs, and they act as an insulator, preserving body heat, and protecting against excessive cold” (673). Once ingested fats are broken down into fatty acids and glycerol, and are divided into 3 different categories, simple fats (triglycerides), compound fats (phospholipides, glucolipids, and lipoproteins), and derived fats (cholesterol). Fats are also further classified as saturated, unsaturated, and polyunsaturated.

Saturated fats are used by the liver to manufacture cholesterol. Cholesterol, is a member of a group of lipids called sterols, and is found only in animal tissues. Cholesterol is important in that it acts as a precursor for the synthesis of various steroid hormones and vitamin D in the body. However, high levels of saturated fat can significantly raise one’s levels of low density lipoprotein cholesterol (LDL’S, bad cholesterol) which is associated with atherosclerosis (hardening of the arteries). Saturated fats can be found in the foods such as: beef, lamb, pork, chicken, shell fish, egg yolks, milk, cheese, butter, and chocolate.

Polyunsaturated fats like saturated fats will also affect your blood cholesterol level. Polyunsaturated fats will lower your blood cholesterol level. However, polyunsaturated fats will lower both your low density lipoprotein cholesterol (LDL’S, bad cholesterol), as well as, lowering your high density lipoprotein cholesterol (HDL’S, good cholesterol). Polyunsaturated fats can be found in foods such as : almonds, pecans, sunflower oil, corn oil, fish, mayonnese, safflower oil, soybean oil, walnuts and in most margarines.

Unsaturated fats will lower your LDL’S (bad cholesterol) without affecting your HDL’S (good cholesterol) making them the healthiest of possible fat sources in the diet. Unsaturated fats can be found in the foods such as: avocados, cashews, olives, olive oil, peanuts, peanut oil, and peanut butter.

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The Merck Manual Seventeenth Edition, Merck Research Laboratories, 1999.

Arnold Schwarzenegger Encyclopedia of Modern Body Building, Simon & Schuster, 1985.

Mosby’s Medical, Nursing, & Allied Health Dictionary, Mosby, 1998.