The Science and Economics of Nutrition, Part 5

In the past few posts, I have talked about the three caloric supports of nutrition -- fats, proteins, and carbohydrates. Carbohydrates only supply energy but fats and proteins also supply necessary "building blocks" for the body to build and repair itself. However, these are not sufficient -- it is also necessary to have other components which we usually call vitamins and minerals.

Vitamins are organic compounds that cannot cannot be synthesized by the human body. Thus, some items (such as Vitamin C) are needed vitamin for humans but not considered such for other animals. Vitamins primarily act as catalysts for building processes within the body. This means that they help the body produce needed cells and substances but are not directly incorporated into the body.

Minerals are often thought of as the "basic elements" such as Calcium, Iron, Copper, and so forth. However, most minerals in the diet are actually combinations of elements -- often with Oxygen but possibly a combination of various elements such as Calcium and Carbon. Since Oxygen is such a high percentage (about 46.6% by weight) of the earth's crust, it has to be expected that Oxygen will be incorporated in many minerals.

Minerals and vitamins interact in various ways. For example, it is difficult for the body to use Calcium unless sufficient quantities of Vitamin D (particularly D3) are present in the diet. On the other hand, if the body doesn't have enough Magnesium, then the Calcium will "substitute" and there might be a deficiency of Calcium available in the body. Some minerals help regulate specific processes in the body -- Chromium is often considered to be important in insulin production within the pancreatic glands.

Vitamins and minerals can be obtained via meats and other animal products. However, since vitamins can be weakened, or destroyed, by cooking, meats are not a preferred source of vitamins.

Fruits and vegetables really shine when it comes to providing the body with vitamins and minerals. They are usually cooked less, or left raw, and this means the nutrients are left intact for the body to use. In addition, the organic compounds which contain the minerals are thought to be better utilized by the body than those from an inorganic source.

Alas, fresh fruits and vegetables are quite expensive on a per-calorie basis. Canned produce are less expensive but often have reduced nutrients due to the canning process and, in the U.S., are often compromised with added salt and sugar. Frozen fruits and vegetables are often the best balance of nutrition and cost -- but, of course, requires a freezer for storage.

One of the biggest challenges in food preparation of fruits and vegetables is countering the media advertising for processed foods. The more processing, the more profits. The more home processing (or preparing a recipe, if you prefer), the more time needed. We will go more into these trade-offs in the next blog, which will be a summary of nutrition with an emphasis on economics.