Carbohydrates

Carbohydrates are macronutrients - foods we need to eat in reasonably large quantities, unlike vitamins and minerals, which are micronutrients and necessary in only small amounts. The two other macronutrients are protein and fat. Carbs are easily converted to energy by the body, so they supply most of our energy needs. There are basically two main classes of carbohydrate - simple carbohydrates and complex carbohydrates- although this classification of carb-types has been superceded by the Glycemic Index (GI) and Glycemic Load (GL).

Types of Carbs

Simple Carbohydrates

Simple carbohydrates (with the exception of fructose, fruit sugar) are basically sugars (glucose) so they are immediately absorbed into the bloodstream, causing a rise in blood-sugar levels. Because blood sugar-levels must be kept within a certain range, the body responds by telling the pancreas to secrete insulin into the digestive system. Why? Because insulin helps to "mop up" excess blood sugar and disperse it to other parts of the body. Unfortunately, the pancreatic gland typically "overreacts" to this sudden rise in blood sugar (thinking a huge amount of food has been eaten) and secretes too much insulin. Result? Within an hour or so, the insulin has mopped up too much blood sugar, so levels drop too far and this triggers hunger. This rapid rise and fall in blood sugar levels caused by excess production of insulin, is not good for our health or our eating habits. Over time, these "sugar spikes" can lead to impaired glucose tolerance, insulin insensitivity and type 2 diabetes. Common sources include table sugar (sucrose), boiled sweets, syrups and honey.

Complex Carbohydrates

By comparison, complex carbohydrates need more time to be broken down into glucose. So they don't raise blood sugar levels as fast as simple carbs. This is why nutritionists recommend that we restrict our consumption of simple carbohydrates and eat complex carbohydrates instead. Complex carbs are either starches, or indigestible dietary fiber. Common sources of starches include, bread, pasta, rice, beans and some vegetables. Common sources of dietary fiber are fruits, vegetables, beans, and the indigestible parts of wholegrains like wheat bran and oatbran. Complex carbohydrate is rich in Nutrition and micronutrients like: Vitamins, Minerals and Phytochemicals.

Dietary fiber, sometimes called roughage, is a group of very complex carbohydrates - found mostly in plants - whose chemical structure prevents them from being digested by humans. Although some metabolism of fiber (by certain bacteria) occurs in the intestines, we lack the digestive enzymes needed to break down the bonds that hold together fiber's sugar units. Therefore, fiber cannot be converted to glucose and contributes no calories to our diet. Most dietary fiber passes through the intestinal tract undigested.

There are two basic types of dietary fiber: soluble and insoluble fiber. The best sources of fiber include beans, wholegrain cereals, fruits, vegetables and nuts. Examples of fiber include: Cellulose, Lignin, Hemicellulose, Pectin, Beta-glucans and Arabinose. Although insoluble fiber and its health benefits have been known for some time, the benefits of soluble fiber have only recently appeared.

Glycemic Index (GI) and Glycemic Load (GL)

Recently, the Glycemic Index (GI) has become the benchmark for classifying carbohydrates. The glycemic index is a measure of how rapidly a particular food causes blood sugar to rise, compared with glucose. Foods are divided into high, medium or low glycemic index foods. The glycemic index, invented in 1981 by David Jenkins and Thomas Wolever of the University of Toronto, is a new system for classifying carbohydrate-containing foods, according to how fast they raise blood-glucose levels inside the body. In simple terms, a food with a higher glycemic value raises blood glucose faster and is less beneficial to blood-sugar control than a food which scores lower.

Although a valuable tool, especially for diabetics, the glycemic index confines itself to measuring a standard amount of carbs (50g). Since some foods contain only a small percentage of carbs, their glycemic index value may not be as relevant as their Glycemic Load, which takes into account portion size and carb content. For example, carrots contain only about 7 percent carbs, so the test-portion of carrots eaten by the test-volunteer will be huge - about 1.5 pounds. Serving sizes of foods (like bread) which contain a higher percentage of carbs, will be smaller.

GLYCEMIC INDEXES OF COMMON FOODS

Breads & Grains
waffle - 76
doughnut - 76
bagel - 72
wheat bread, white - 70
bread, whole wheat - 69
cornmeal - 68
bran muffin - 60
rice, white - 56
rice, instant - 91
rice, brown - 55
bulgur - 48
spaghetti, white - 41
whole wheat - 37
wheat kernels - 41
barley - 25

Cereals
Rice Krispies - 82
Grape Nuts Flakes - 80
corn Flakes - 77
Cheerios - 74
shredded wheat - 69
Grape Nuts 67
Life - 66
oatmeal - 61
All Bran - 42

Fruits
watermelon - 72
pineapple - 66
raisins - 64
banana - 53
grapes - 52
orange - 43
pear - 36
apple - 36

Starchy Vegetables
potatoes, baked - 83
potatoes, instant - 83
potatoes, mashed - 73
carrots - 71
sweet potatoes - 54
green peas - 48

Legumes
baked beans - 48
chick peas - 33
butter beans - 31
lentils - 29
kidney beans - 27
soy beans - 18

Dairy
ice cream - 61
yogurt, sweetened - 33
milk, full fat - 27
milk, skim - 32

Snacks
rice cakes - 82
jelly beans - 80
graham crackers - 74
corn chips - 73
life savers - 70
angel food cake - 67
wheat crackers - 67
popcorn - 55
oatmeal cookies - 55
potato chips - 54
chocolate - 49
banana cake - 47
peanuts - 14

Sugars
honey - 73
sucrose - 65
lactose - 46
fructose - 23

Beverages
soft drinks - 68
orange juice - 57
apple juice - 41

Proper nutrition and a balanced diet supplement is essential. When this is accomplished, any individual can enhance their health. At Supplement Central, it is easy to find just what you need and get information about carbohydrates and other nutrients. If you have questions, or are ready to start experiencing these benefits in your life contact us today.