Why Proteins Are Important

If glucose is “fuel” for the body, protein is “building material”. It builds blood, muscles, organs, skin, hair, nails. Protein is formed of 22 amino acids, eight of which the body is not able to produce, and must come from our diet. These are called essential amino acids. All amino acids must be present for the production of protein, tissue building, creating the hormones, enzymes and other functions. The excess protein we consume is converted to fat. Protein is converted to energy only when glucose and fat storage are complete.

Why Fats Are Important

Fats are a secondary, very concentrated, source of energy that our body uses. We can either eat fat, or produce it from excess glucose. The human body stores as fat all the energy it does not need for the burning processes. In fact, our body is a very “low consumption machine”. It uses as little as possible energy for burning, and stores more for rainy days. Fat dissolves and carries some of the vitamins that are not water-soluble. Like proteins, fats include some essential fatty acids that the body cannot produce and thus must be provided by food. Fatty acids can be saturated, mono unsaturated and polyunsaturated.

Fats or lipids are stored in fat cells. We are born with some of these fat cells. The rest develop at puberty. After this period, fat cells do not multiply anymore. They can enlarge and store more lipids. The fat we ingest is carried into the fat cells through a complex process. This process depends on the insulin level in the blood. Insulin activates enzymes called lipoprotein lipases which break down the fats into fatty acids.

Eating too many saturated fats is associated with high LDL cholesterol levels. LDL cholesterol is also known as “bad cholesterol” and causes blood-vessel diseases. Mono- and polyunsaturated fats provide both LDL and HDL cholesterol.

Cholesterol is a fat-like substance that belongs to the steroids group. Cholesterol insulates cells and protects them from temperature variations, to help create sex hormones, bile salts, (to help digestion), and produce vitamin D in skin tissue when exposed to the sun.

Our body is able to produce the cholesterol it needs to function properly. But we also ingest cholesterol. The discussion about “good” and “bad” doesn't refer to cholesterol itself but to the molecules that carry it.

Apoproteins are compounds that can dissolve and carry cholesterol and lipids. Apoproteins combined with lipids form lipoproteins. “Bad cholesterol” is in fact Low Density Lipoprotein and “good cholesterol” is High Density Lipoprotein. HDL is able to solve and carry lipids and cholesterol, while LDL is less able to do that. When we go to the doctor and ask for a cholesterol level test, he or she measures total cholesterol, HDL and LDL levels in the bloodstream. Two situations are considered “high heart attack risk”:

• High total cholesterol levels in the blood, even if the HDL/LDL ratio is good;
• High LDL levels, even though total cholesterol levels are low.