subject: The Glycemic Index And The Glycemic Load [print this page] This article will tell you everything you need to know about Glycemia, the Glycemic Index, the Glycemic Load and the two magic letters, GI.
What is The Glycemic Index?
The Glycemic Index (glycaemic index or GI) is a measure of the effects of carbohydrates on blood glucose levels (or blood sugar levels) when a particular food is eaten. Some carbohydrates that convert to blood sugar faster then the others releasing glucose rapidly into the bloodstream, have a higher GI (gi index varies from 1 to 100). Foods with a low GI rating will be absorbed more slowly, helping to keep blood sugar levels constant. For most people, foods with a low GI have significant health benefits. The research carried out by Dr. David J. Jenkins and colleagues in 1980-1981 at the University of Toronto found that foods with low GI were best for people with diabetes
Eating high-glycemic carbohydrates (ones that turn to sugar quickly) will hinder the fat burning process and will decrease energy levels. When you eat high-glycemic carbs, your blood sugar levels go up rapidly; when this happens your pancreas produces insulin. One of the roles of insulin is to keep your blood sugar levels regulated - but it's also a storage hormone to clear the excess sugars. Those sugars end up in fatty tissue. Basically, you're gaining fat, because internally, you're telling your body to store. When overproduced insulin clears the sugars out of your blood - the end result is that your blood sugar levels are lower than they should be, "you crash" or get lethargic, and now your body craves sugars. Next, you end up overeating, and the cycle continues
When you are switching to low-glycemic carbs, the energy release is gradual and long lasting which is ideal for athletes, you do not tax your pancreas and over-produce insulin (a storage hormone), you feel better and you're in a better position to lose weight or more accurately, burn body fat.
How to lower the Glycemic Index:
Glycemia or glycmia is the concentration of glucose in the blood. It will fluctuate up or down after meals, dependant on the types of food eaten.
The glycemic effect of foods depends on a number of factors such as the type of starch, fat and protein content of the food and organic acids or their salts in the meal - adding vinegar for example, will lower the GI. The presence of fat or soluble dietary fibre can slow the gastric emptying rate thus lowering the GI. Recent studies have shown that the consumption of an alcoholic drink prior to a meal reduces the GI of the meal by approximately 15%.
o Use breakfast cereals based on oats, barley and bran
o Use breads with wholegrains, stone-ground flour, sour dough
o Reduce the amount of potatoes you eat
o Enjoy all other types of fruit and vegetables
o Use Basmati or Doongara rice
o Enjoy pasta, noodles, quinoa
o Eat plenty of salad vegetables with a vinaigrette dressing
Popular Low Glycemic Diets:
Glycemic Impact Diet: a very good diet, takes the best of the Zone and South Beach Diet.
Glycemic Load Diet: Glycemic Index corrected for serving size is the Glycemic Load - the diet aims to produce healthy weight by maintaining a daily load under 500 on the Index
Nutrisystem: portion-controlled program, based around low-glycemic foods.
Sugar solutions: a diet to correct blood sugar imbalances (from Prevention magazine).
South Beach Diet: Carb choices are based around low-glycemic foods - although the diet begins with a very low carbohydrate phase.
One of the biggest selling books about Gi diet is The New Glucose Revolution%u2026 Also, Rick Gallop's The GI Diet is very popular book.
Example of Low Glycemic Diet:
A typical low glycemic index diet is low in fat and high in carbohydrates - but specifically low-GI carbs. Often a simple change from high GI carbs, to low GI carbs may bring about weight loss. It may also give the feeling of more energy, due to less blood sugar / insulin spikes during the day.
Breakfast - Oatmeal with raisins and skim milk. Orange juice.
Lunch - Vegetable soup with sourdough bread followed by Plums.
Dinner - Lean beef bolognese on wholemeal pasta with a Green salad. Followed by a Low-fat yogurt.
Drinks - Water, tea (skim milk), herbal teas.
The Glycemic Load
The glycemic load (GL) is a ranking system for carbohydrate content in food portions based on the portion size and their glycemic index (GI). The glycemic load was created by Harvard researchers and based on the idea that high glycemic index food consumed in small quantities would give the same effect as larger quantities of a low glycemic index food on blood sugar. For example, white rice has a high GI, so eating 50g of white rice at one sitting would give a particular glucose curve in the blood, while 25g would give the same curve but half the height. Since the peak height is probably the most important parameter for diabetes control, multiplying the amount of carbohydrates in a food serving by the glycemic index gives an idea of how much effect an actual portion of food has on blood sugar level.
Glycemic load (for a single serving of a food) can be calculated as the quantity (in grams) of its carbohydrate content, multiplied by its GI, and divided by 100.
Glycemic Load = (Carbohydrate Content x GI) : 100
For example, a 100g slice serving of Corn tortilla with a GI of 52 and a carbohydrate content of 48g makes the calculation 48*0.52=25, so the GL is 25.
10 or less - low glycemic load
11-19 - medium GL
20 or greater - high GL
In a study which appeared in the International Journal of Obesity recently, it was reported by Canadian scientists that mice who had a natural tendency to be obese and diabetic, reduced their glycemia levels by 35% when fed fermented blueberry juice. So maybe blueberries which have properties to assist protecting from cancer, may also assist with weight loss.
