Glycemic Index - preventing obesity, diabetes and heart disease.
The glycemic index (GI) of carbohydrates compares their ability to release glucose into the blood (and therefore stimulate insulin secretion) with that of an equivalent weight of pure glucose (glycemic index 100).
All carbohydrates increase blood sugar levels (and so have a glycemic index) and therefore cause insulin to be released from the pancreas in order to control the amount of glucose in the blood. The more glucose that has been made available in the blood, the more insulin is released to control it. The relative effciency with which carbohydrates do this is known as the glycemic index.
The importance of the glycemic index is that it predicts how much insulin will be released and therefore, how the body will respond. For example metabolise fat (use it for fuel - low glycemic index) or store excess energy as fat (high glycemic index).
This happens in two ways.
Firstly, the presence of insulin (high glycemic index) instructs the liver that energy requirements are more than being met by current food intake, so the breakdown of fat to provide energy from body stores is unnecessary. Therefore, insulin (and so high glycemic index) stops the body from burning fat for energy.
Secondly, and at the same time, excess sugar in the blood is quickly targeted to be stored for later energy requirements and is converted to fat. So, insulin ( and high glycemic index) also causes the body to store more fat.
If the blood sugar level remains high, i.e. with really high glycemic index foods, more insulin is released in an effort to reduce it.
From these two very simple rules, it should be easy to see that any high glycemic index food that causes sudden increases in blood sugar and therefore massive release of insulin is likely to lead to increased fat production and storage.
Not surprisingly, therefore, people who eat a lot of sugary foods and other foods with a high glycemic index, such as refined flour, potatoes, white rice and cereal-based foods are more likely to retain fat than those that don't. Unfortunately, this is exactly what we are told to do by modern medicine and Government, who clearly have no idea about weight control. For more information on how this affects those who are overweight and how to safely lose weight, click here.
The following table gives an indication of the relative glycemic index of various foods.
Glycemic index of popular foods
||Rye bread (crispbread)
||Muesli (no sugar)
|Biscuits / cookies
|Cornflakes / cereal
||Sultanas / raisins
||Oatmeal biscuits / cookies
||High water content fruits (melon etc)
*the Glycemic index of Maltose is actually higher than that of glucose. i.e. malt and it's products (like beer) actually stimulate more insulin release than pure sugar!
What is clear from this table is that different varieties of similar foods have different effects. For example, boiled potatoes have a lower Glycemic index than baked potatoes and wholewheat varieties of bread and pasta are much better than their white counterparts. This effect on glycemic index is explained below.
The effect of eating high glycemic index foods consistently is to lead to constantly high insulin levels. In this situation, the body becomes accustomed to these high insulin levels and starts to respond to them less effectively over time. As high glycemic index foods are eaten further, this progresses, more and more insulin is required to have the same effect on the tissues. This phenomenon is known as insulin resistance, and is the first step towards diabetes.
The glycemic index situation is made worse if the body has insufficient chromium. Chromium helps insulin to exert its effect on the tissues, encouraging sugar uptake and thereby reducing blood sugar. In the absence of chromium, insulin is much less effective, sugar levels stay high and MORE insulin is secreted in an effort to control them
The Good News
Thankfully, it is not all bad news. Whilst It is best to avoid foods with a high glycemic index, they often have direct alternatives with a moderate or even low glycemic index. This is because the insulin-stimulating effect of carbohydrates is greatly reduced in the presence of fibre, as found in some fruits and the wheatgerm present in whole wheat. This moderates the insulin response, spreading out the absorption of carbohydrate over a prolonged timespan and so reduces the amount of insulin released (lower glycemic index.
In addition, the use of chromium supplements makes insulin's job easier, helping reduce blood glucose (and therefore insulin) to normal levels.
In this way, the effect of brown rice and wholewheat alternatives to white flour products is much lower, and therefore much less detrimental to health. This is why it is best to ALWAYS use wholewheat / wholegrain versions of these foods, with a lower glycemic index.
Glycemic Index, Insulin resistance and diabetes.
Whilst diabetes is discussed elsewhere on this site, it is worth touching here on the role of insulin resistance in the development of the disease.
Diabetes is the inability of the body to produce enough insulin to control blood sugar. As a consequence, those who suffer from diabetes suffer from a number of problems related to the massive spikes of sugar immediately following a meal and subsequent troughs in between meals, which, if unchecked can lead very quickly to coma and death.
It has long been known that frank diabetes is often, indeed usually preceded by a period of insulin resistance, in which, as described above, more and more insulin is released with each subsequent dose of high glycemic index carbohydrate in order to overcome the increasing insensitivity of the tissues to insulin's "demands".
Eventually, the body reaches a stage where, no matter how much insulin is produced, the tissues no longer respond and blood sugar remains unchecked. In such a situation, the pancreas can "give up" completely, and all insulin secretion may stop. Whether this happens or not, diabetes is the result, and huge doses of insulin are required to be injected to overcome the problem, regardless of glycemic index. Needless to say, the high insulin levels mean that many diabetics are overweight. This adds further stress to the system.
Prior to this "end stage" diabetes, there is much to be gained from limiting the intake of high (and even medium) Glycemic index foods (not just sugar, as advised by medicine) and taking an appropriate dose of chromium supplements to make the existing insulin more effective.
Clich here for more information on diabetes.
Conquering diabetes using natural methods
Conquering weight loss using natural methods
Conquering heart disease using natural methods
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