Understanding Glycemic Index and Glycemic Load

W hen we eat food that contains carbohydrate, then our digestive system changes carbohydrates into glucose which is then released into the blood hence called (blood sugar or Blood glucose). Glucose is the major source of energy for cells of our Body; however the cells cannot take energy directly from the glucose.

 

On sensing the rise of glucose level in the blood, the Beta cells of the pancreas work to release Insulin a hormone, essentially required to enable cells of our body to transform glucose from the blood stream into energy. Thus glucose level in the blood decreases.

On sensing the low glucose level in the blood, the Alpha cells of pancreas release Glucagon. Glucagon causes the liver to release stored glucose from its cells into the blood to keep blood glucose levels high enough for the body to function well. This is normal process of our body to get energy from food.

Then the question is why and what is this Hullaballoo (hue and cry) concerning GI and GL all about?
Why should we all get to know G Index and G Load and Insulin. The answer is that since from the last century till today, the rate of occurrence of diseases like obesity and diabetes, both in adults and children, has skyrocketed.

 

Research studies were and are being done to understand the reason and to find the solution.
Read more at http://www.who.int/dietphysicalactivity/childhood_why/en/

Causes

Up to today the available evidence from a large number of the reliable, honest scientific research studies, carried out since past centuries until now, clearly implicate the highly refined unnatural bad carbohydrates, which are in the form of fiber removed highly processed foods and fruit juice, sugar-sweetened beverage in the modern human diet is one of the main culprits causing obesity and diabetes, stroke, heart and other diseases.

What is reliable research studies? Read here, What is correct information

Obesity is, then, a well-known precursor to a host of diseases like cancer and heart disease.

Read more here  http://www.nhlbi.nih.gov/health/health-topics/topics/obe/risks

Fiber removed highly processed food like white bread, white rice potatoes chips, cookies and bakery products and such foods, are digested very quickly and turned into glucose and this causes spikes the blood sugar level.
Point to note is that the quick, sudden, and excess spikes in blood sugar levels caused by the release of glucose into the blood, puts an abnormal work load on pancreatic cells - striving to supply insulin - in response to the rise of glucose in blood stream, which, is a health concern.

Body is adapted to digest carbohydrate rich foods (Minimal cooked) and its conversion into glucose from only those carbohydrate foods which contain both digestible and indigestible fibers. Natural Fiber content in the food resist digestion which then helps the digestive system to do some exercise in obtaining glucose from the food thereby releasing it into blood, slowly and steadily.
Pancreatic beta cells are adapted to releasing insulin towards its obligation in coordinating with this evolved metabolic system of our body. This process generates strong satiety sensations and means one does not feel hungry for a longer period of time.

Read more at http://www.ncbi.nlm.nih.gov/pubmed/15662001

Both digestible and indigestible natural fibers in natural raw or very lightly processed foods have a very vital role and are integral to maintaining, healthy gut flora, digestive and overall health.

The relatively recent abuse and high handedness we perpetuate by forcing our body to digest fiber removed, unnatural, highly processed junk food and fluid; paralyzing our cells and genes by denying them opportunity to remain active and fit because of our sedentary lifestyle, is an emerging uncivilized behavior of modern society against the development, over millions of years, of our civilized, trusted, obedient and responsible system of cells and genes that make up the Human Body. This is a major cause of the crisis of the obesity pandemic, and can be suspected as one of the causes of diabetes and other diseases, together termed as metabolic disorder.

Solution

Among Various measures to educate people on controlling blood glucose (blood sugar) to avoid obesity and diabetes, and for living a healthy life, scientists advise people to know the carbohydrate contents in the foods we eat, and for this purpose they have indexed in three categories High, Medium, and Low in the Glycemic Index carbohydrate containing food.

The indexing of carbfood is in accordance with their carbohydrate contents and its effect on the blood glucose level.

Slowly absorbed carb foods which are slowly digested and converted into Glucose are in low and medium GI rating, while foods that are more quickly digested and transformed into glucose have a higher rating and are in High glycemic Index.

The Glycemic Index Chart has been developed for the purpose of enabling people specially, obese and diabetic patient, to understand and chose carbohydrates that are slowly absorbed and converted into glucose in the digestive tract.

Glycemic Index uses a scale of 0 to 100.

Read more at, https://en.wikipedia.org/wiki/Glycemic_index

With higher values given to foods that contains highest level of carbohydrate. Pure glucose serves as a reference point, and is given a Glycemic Index (GI) of 100.

However understanding GI alone is not enough to avoid quick, sudden, excess release of glucose in the blood which spark and spike the blood glucose level.
Because all carbohydrate containing foods, even those which are in high GI, may not be digested at the same rate, when eaten in moderation, will not usually end up into excess glucose, and will not cause the unhealthy rise of glucose and insulin interaction condition in our body.

Examples are the many natural food that are sweet (high carb containing) yet health promoting, nutritiously dense, lovely fruits, like these poor chaps...

watermelon, and carrot, .

They have also been arrayed in High Glycemic Index, along with these high carb containing unhealthy nasty food like, sugary drinks, white bread, cookies, white rice and other refined foods.

By the rule of sense and science the natural high carb food like mango papaya, dates, grapes and all other sweet fruits which humans are adapted to metabolize for the millions of years cannot pose a health concern, if eaten in moderation and in accordance with the health condition, and the nutritional requirement of an individual.

The second point is although watermelon and carrot do have high contents of carbs, and so are incarcerated in High Glycemic Index along with those unhealthy high carb containing foods, but watermelon and carrot cannot be eaten in access amount due to its water and fiber contents, thus cannot be a concern of the unhealthy rise of glucose and insulin level in blood.
Rather mounting evidences are supporting the beneficial health effects of eating watermelon and carrot in moderation.

So what? Should we neglect and dismiss the idea of Glycemic index?

Certainly not. Instead, while having the knowledge of Carb contents in a food, additionally we need to understand how much of that carbohydrate containing food we eat will end up in glucose, and how much it will affect the rise of glucose in our blood stream.
This idea has been explained by Harvard scientists in the term of Glycemic Load.

What Is the Glycemic Load (GL)?

Glycemic Load means the impact of foods on our actual blood sugar level. While the GI gives us an idea about the total amount of carbohydrates in foods in their unconsumed state, GL is the measures of the actual impact of the carb-foods when eaten, on our blood sugar status.

The amount of carb contents in the food explained in glycemic Index, and its actual impact on the blood glucose level greatly differ in accordance with kind and amount of carb containing food eaten. In another word GI explains the quantity of carbohydrate in the food while GL is a measure of the quality of the carb.

The amount (quantity) of carb in GI and the kind (quality) of carbohydrate GL help us understand the ability of the food (when consumed) on influencing the Insulin and glucose interaction and their level in the blood.

Comment

A high dietary glycemic loads diet, mostly from fiber depleted unnatural food, will certainly cause obesity and will greatly increase the risk of developing type 2 diabetes mellitus (DM).

Insulin does mediate blood glucose entry into the cells for using it as energy, but insulin also signals the liver and muscle tissues to store the excess as fat in the body.

However eating low GI and GL food alone will not be enough to get health benefits, as reported in the article publiahed in JAMA on 17th December 2014. Effects of High vs Low Glycemic Index of Dietary Carbohydrate on Cardiovascular Disease Risk Factors and Insulin Sensitivity

Maintaing a healthy glucose and insulin interaction condition (Glucose Homeostasis), knowledge of Glycemic Index, Glycemic load and ‘calorie in and out' as a part of Intelligent Eating of an individually suitable Balanced Diet focused on overall health, while pursuing for Buddhi and understanding the factors which impact health, will be a correct strategy to avoid the avoidable diseases like obesity, CVD, cancer and others, and enable us to reap the health benefit from the messages of honest research studies.

Suggested site for more information:

Biology of Ageing "Insulin Plays Central Role In Aging, Brown Scientists Discover." Brown University.

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