There are countless diet types that have been discussed or recommended over the years. Some of the more well known are:

Atkins     Sonoma      Zone      Mediterranean     Vegan

 

 
     Negative Calorie     Vegetarian     Blood Type

    These, along with others, could keep you going around in circles so let's focus on what can be agreed upon. There are six basic nutrients necessary to good health – Carbohydrates, Fat, Protein, Vitamins, Minerals and Water. The first three can be transformed by the body (to calories) for energy. 1 gram of carbohydrate or 1 gram of protein equals 4 grams of calories. 1 gram of fat equals 9 grams of calories.

    The easiest nutrients for the body to use as energy are carbs which convert to sugar (glucose) during digestion and are released into the bloodstream. Excess sugars are stored as fat. There are two kinds of carbohydrate, simple and complex.. Simple carbohydrates break down quickly and flood the bloodstream with sugar. The body responds with an overproduction of insulin designed to regulate the blood sugar level. It does this by quickly converting the sugar to fat. Complex carbohydrates break down much more slowly giving you sustained energy and avoiding the insulin response.

    Carbs are classified as simple or complex by their placement in the Glycemic index. The glycemic index (GI) is a ranking of carbohydrates on a scale from 0 to 100 according to the extent to which they raise blood sugar levels after eating. Foods with a high GI are those which are rapidly digested, absorbed and result in marked fluctuations in blood sugar levels. Low-GI foods, by virtue of their slow digestion and absorption, produce gradual rises in blood sugar and insulin levels, and have proven benefits for health. Typically, processed sugars and starches are not only high GI, but have little or no nutritional value and should be avoided. Perhaps more important than the quantity of carbs you consume is the quality. Best bet; get most of your carbs from fresh fruits and vegetables.

    Fat is the next source of energy when sugars begin to run low. This is the point of the low carb diets. If no sugars are available, the body must use the fat stores as energy. Of course not all fat is bad and some is necessary for good health. Without it the body could not process “fat soluble” vitamins A, D, E and K, which are essential to good health. There are several types of fat.

    Saturated fat is the one most strongly linked to high cholesterol and heart disease. Examples are butter, lard, coconut oil, palm kernel oil and dairy products.

    Polyunsaturated fatty acids are found in vegetable and fish oils. The two essential fatty acids, Linoleic Acid and Alpha Linoleic Acid, as well as omega 3's, are found here. These are necessary for good health and must be gotten from the diet as the body cannot manufacture them from other fats. Fish is an excellent source.

    Mono unsaturated fats are abundant in olive oil and canola oil. This type of fat is also of interest because it may play a role in reducing the risk of health problems, such as heart disease and possibly even some cancers.

    Hydrogenated fats and trans fatty acids are polyunsaturated fats that have undergone a man made process to convert them to saturated fats. Corn oil is hydrogenated into margarine. Researchers believe they have some of the same harmful properties associated with the saturated fats that occur naturally. Others believe they are worse as the hydrogenation changes the shape and structure of the fatty acids into a form — known as “trans” — that would not otherwise occur. The body utilizes this form in a way that is different from its use of the original fatty acids.

    Best bet; see that the majority of the fat in your diet is unsaturated.

      Protein can be converted into energy, but it's primary job in the body is to provide the building blocks needed for growth, repair, and the maintenance of body tissues. Protein is found in practically every food. Some of the richest sources of protein are meat, eggs, dairy products, beans and nuts.

    During digestion, protein is broken down into the building blocks used to repair the body known as Amino Acids. There are 20 Amino Acids, 9 of which are essential (must be gotten from diet, they are required by the body but cannot be manufactured). While most foods contain protein, only animal protein contains all 9 essential amino acids in proportion and is therefore considered “complete protein”. Vegetable protein is incomplete because each source is low in one or more essential amino acids. Proteins from different plants may be combined to provide complete protein for the body. This is also the body's last line of energy. Once all fat reserves have have been utilized, the body will begin to break down muscle tissues for fuel. However a surplus of amino acids in the bloodstream will also be converted to fat.