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Nutrition Basics

Nutrition studies how our bodies use food as fuel for growth, sustenance and daily activities. The macronutrients, or "big" nutrients include proteins, carbohydrates, and fats. The micronutrients, or "little" nutrients are the vitamins and minerals that are required for general health.

Nutrition studies how our bodies use food as fuel for growth, sustenance and daily activities. The macronutrients, or "big" nutrients include proteins, carbohydrates, and fats. The micronutrients, or "little" nutrients are the vitamins and minerals that are required for general health.

Let’s take a look at macronutrients. As mentioned earlier these are the proteins, carbohydrates and fats that provide energy and the raw materials your body needs to stay alive.

Carbohydrates, proteins, and fats supply 90% of the dry weight of the diet and 100% of its energy. As sources of energy, carbohydrates, proteins, and fats are interchangeable in proportion to their energy content. The energy content is 4 calories in a gram of carbohydrate or protein and 9 calories in a gram of fat (1 gram equals 1/28 ounce). However, these nutrients differ in how quickly they supply energy; carbohydrates are the quickest, and fats are the slowest.

Carbohydrates, proteins, and fats are digested in the intestine, where they are broken down into their basic units: carbohydrates into sugars, proteins into amino acids, and fats into fatty acids and glycerol. The body uses these basic units to build substances it needs for growth, maintenance, and activity (including other carbohydrates, proteins, and fats).

Carbohydrates: Depending on the size of the molecule, carbohydrates may be simple or complex. Simple carbohydrates are various forms of sugar, such as glucose and fructose. Because they are small molecules, they can be broken down by the body quickly and are the quickest source of energy. Fruits, dairy products, honey, and maple syrup contain large amounts of simple carbohydrates, which provide the sweet taste in most candies and cakes.

Complex carbohydrates are composed of long strings of simple carbohydrates. Because complex carbohydrates are larger molecules than simple carbohydrates, they are slower sources of energy. However, energy can be generated from them relatively quickly. Complex carbohydrates occur in wheat products (such as breads and pastas), other grains (such as rye and corn), beans, and root vegetables (such as potatoes).

The body stores very small amounts of excess energy as carbohydrates. The liver stores some as glycogen, a complex carbohydrate that the body can easily and rapidly convert to energy. Muscles also store glycogen, which they use during periods of intense exercise. The amount of carbohydrates stored as glycogen provides almost a day's worth of calories. A few other body tissues store carbohydrates as complex carbohydrates that cannot be used to provide energy.

Most authorities recommend that about 50 to 55% of the total daily calories should consist of carbohydrates.

Proteins: Proteins consist of units called amino acids, strung together in complex formations. Because proteins are complex molecules, the body takes longer to break them down. As a result, they are a much slower and longer-lasting source of energy than carbohydrates. There are 20 amino acids. The body synthesizes some of them from components within the body, but it cannot synthesize nine of the amino acids—called essential amino acids. They must be consumed in the diet. They include histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

The body contains large amounts of protein. Protein, the main building block in the body, is the primary component of most cells. For example, muscle, connective tissues, and skin are all built of protein.

Adults need to eat about 60 grams of protein per day (0.8 grams per kilogram of weight or 10 to 15% of total calories). Adults who are trying to build muscle need slightly more. Children also need more. If more protein is consumed than is needed, the body does not build more protein (or muscle). Instead, the body breaks the protein down and stores its components as fat, which can be broken down and used for energy later as needed.

Fats: These complex molecules are composed of fatty acids and glycerol. Fats are the slowest source of energy but the most energy-efficient form of food. Each gram of fat supplies the body with about 9 calories, more than twice that supplied by proteins or carbohydrates. Because fats are such an efficient form of energy, the body stores any excess energy as fat. The body deposits excess fat in the abdomen (omental fat) and under the skin (subcutaneous fat) to use when it needs more energy. The body also stores excess fat in blood vessels and within organs, where it blocks blood flow and damages the organs, often with devastating results.

The body cannot synthesize some fatty acids—called essential fatty acids. They must be consumed in the diet. The essential fatty acids make up about 7% of the fat consumed in a normal diet and about 3% of total calories (about 8 grams). They include linoleic acid, linolenic acid, arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid. Linoleic acid and linolenic acid are found in vegetable oils. Eicosapentaenoic acid and docosahexaenoic acid, which are essential for brain development, are found in fish oils. In the body, arachidonic acid can be formed from linoleic acid, and eicosapentaenoic and docosahexaenoic acid can be formed from linolenic acid, although fish oil is a more efficient source.

Now let’s move into the realm of the micronutrient. Micronutrients do not provide energy for the body, but they are necessary to carry out most of the biochemical processes that go on. A healthy diet can provide the vitamins and minerals you need, however there are times when dietary supplements are important too.

Vitamins are organic compounds that the human body cannot produce and therefore must acquire through the diet. To help maintain good health, humans need 13 different vitamins. These include: vitamin A, the various B and D vitamins, vitamin C, vitamin E, and vitamin K. Deficiencies of these essential vitamins can cause the body to enter a diseased state. Deficiencies of different vitamins manifest themselves with differing diseased states. For example, night-blindness is linked to vitamin A deficiency, while Rickets is linked to vitamin D deficiency.

The relationship between foods and maintaining health has been recognized for centuries. For example, in 1747, Dr. James Lind discovered that citrus fruits prevented scurvy. Some stores of vitamins within the body can last well over a year, as is the case with vitamin 12. Others can deplete more rapidly lasting only a couple of weeks. A vitamin can be either fat or water soluble. Water-soluble vitamins are not stored in the body. Often they need to be replenished more frequently. Fat-soluble vitamins, however, are stored in the body. Excessive intake of fat-soluble vitamins can cause toxicity in the body. Fat-soluble vitamins include A, E, D and K.

Today there is debate among experts over the benefits of vitamin supplements. Some believe supplements must be taken in conjunction with the daily diet. This is because many foods are processed and artificially enriched which can reduce the nutrient level naturally found in these foods. Moreover, even fresh fruits and vegetables are picked prematurely and shipped long distances before arriving on grocery shelves. For this reason, some physicians recommend taking vitamins.

Minerals are inorganic substances like sodium, potassium, chlorine, calcium, phosphorus, magnesium, iodine, iron, cobalt, and copper. They are classified into two categories: major and minor, based on the intake level.

If more than 100 mg of a mineral is required per day, the mineral is classified as a Major mineral. Major minerals include calcium, phosphorus, potassium, sodium, chlorine, magnesium, and sulfur.

Minor or trace minerals include boron, chromium, cobalt, fluorine, iodine, iron, manganese, molybdenum, selenium, silicon, vanadium, and zinc. Here are some quick facts that you may find relevant about minerals:

• Plants incorporate minerals from the soil into their own tissues. For this reason fruits, vegetables, grains, legumes, nuts and seeds are often excellent sources of minerals.


• Minerals - as they occur in the earth in their natural form - are inorganic or lifeless. In plants, however, most minerals are combined with organic molecules. This usually results in better mineral absorption. Green leafy vegetables are the best source of many minerals.


• Minerals are vital for good health. Like vitamins they are essential for regulating and building the cells which make up the body. Body cells receive the essential food elements through the bloodstream. They must, therefore, be properly nourished with an adequate supply of all the essential minerals for the efficient functioning of the body.


• Minerals help to maintain the volume of water necessary for the life processes in the body. They help draw chemical substances into and out of the cells, and keep the blood and tissue fluids from becoming either too acidic or too alkaline.


• The importance of minerals, like vitamins, is illustrated by the fact that there are over 50,000 enzymes in the body which direct growth and energy, and each enzyme has minerals and vitamins associated with it. Each of the essential food minerals does a specific job in the body, while some of them do extra work in teams to keep the body cells healthy.


• Minerals thus play an important role in bodily functions and are present in every human cell. Although the amount needed may be small, even the lack of the required trace of the mineral is bound to lead to a dysfunction at some level in the body.


• Less obvious deficiencies may surface as fatigue, irritability, loss of memory, nervousness, depression, and weakness.


• These inorganic minerals are essential for the proper growth and assimilation of the organic substances, and development of every part of the body.


• The body can tolerate a deficiency of vitamins for a relatively long period, but even slight changes in the concentration of the important minerals in the blood may rapidly endanger life.

(Some mineral information)

Boron - Prevents Tumours and Cysts

Calcium - For Strong bones

Chlorine - The Natural Disinfectant

Chromium - Enhances Glucose Tolerance

Copper - Converts Iron into Hemoglobin

Fluorine - For Healthy Teeth

Iodine - Prevents Goitre

Iron - Purifies the Blood

Magnesium - The Alcoholic’s Balm

Manganese - For Growing Years

Molybdenum - For General Well Being

Phosphorus - The Body Energizer

Potassium - To prevent Acidosis

Selenium - A Women’s friend

Silicon - The Beauty Mineral

Sodium - Indispensable for Life

Sulphur - For Glowing Hair and Skin

Vanadium - For Healthy Heart

Zinc - For Faster Healing