Time to retire the Glycemic Index. The Insulin Index has also failed, big time.

Purportedly, the Glycemic Index (GI) helps consumers make better carbohydrate choices by ranking foods according to their capacity for increasing blood sugar levels.

The official international GI database is maintained by the University of Sydney. To determine GI values, measured portions of particular foods containing 50 grams of available carbohydrate (or 25 grams of available carbohydrate for foods that contain lower amounts of carbohydrate) are fed to 10 healthy people after an overnight fast.

Finger-prick blood samples are taken at 15-30 minute intervals for two hours the following morning. These blood samples are used to construct a blood sugar response curve for the two hour period. The incremental area under the curve (iAUC) is calculated to reflect the total rise in blood glucose levels after eating the test food.

The GI value is calculated by dividing the iAUC for the test food by the iAUC for the reference food (same amount of glucose) and multiplying by 100. The average of the GI ratings from all ten subjects is published as the GI for that food.

The GI has two primary limitations.

First, because fructose generally registers low GI scores, some fructose-containing foods are presumed to be healthy, even if they are not. Here, we’re mostly concerned with “free sugar” products, meaning products that have little to no fiber and are pure sugar. Examples included agave syrup and coconut sugar, both of which are frequently advertised as “healthy” because of their low glycemic indexes.

Agave may indeed have a lower GI than sucrose (table sugar), but that doesn’t make it any healthier. The same problem occurs regarding fruit juice. If you search the GI database, you’ll find that apple juice, orange juice, and carrot juice all have low GI scores.

Orange juice can even have a lower GI (46) than whole oranges (ranges from 31 to 48). Note that any score under 55 is considered “low.”

Juices are loaded with concentrated sugar and promote serious metabolic damage when consumed excessively. If we use the GI to make food choices, we might incorrectly presume that agave syrup and fruit juices are health-supportive foods.

More on this article here.

http://www.christopherjamesclark.com/blog/time-to-retire-the-glycemic-index/

BTW The same people behind the insulin index are also responsible for the gylcemic index. One of the main people behind both indexes Jenny Brand Miller was also involved with this paper.

The paper was published last week (Augustin LS, Kendall CW, Jenkins DJ, Willett WC, Astrup A, Barclay AW, Bjorck I, Brand-Miller JC, Brighenti F, Buyken AE et al: Glycemic index, glycemic load and glycemic response: An International Scientific Consensus Summit from the International Carbohydrate Quality Consortium (ICQC). Nutr Metab Cardiovasc Dis 2015, 25(9):795-815.

"As indicated by the title, responsibility was taken by the self-proclaimed ICQC. It turned out to be a continuation of the long-standing attempt to use the glycemic index to co-opt the obvious benefits in control of the glucose-insulin axis while simultaneously attacking real low-carbohydrate diets."

Full story here.

http://feinmantheother.com/2015/12/01/stone-walling-low-carbohydrate-diets-attack-of-the-self-proclaimed-icqc/

Call me an old cynic, but can anyone remember the guy who worked overtime to flog us the insulin index on this forum, went by the name of Marty Kendall. That's the guy Indy worked tirelessly to promote around the internet, and walked off in a strop from here because I did not buy Marty's BS. Could this CW Kendall be a relation of Marty's we need to be told.

As always follow the money. Or those trying to make money.

Time to retire the glycemic index? More like time to give it a christian burial! Just look over at DCUK and the success stories over there-I don't remember seeing a shed load of threads regarding uncontrolled diabetes turnarounds that were down to a low GI diet-nearly all are down to low/reduced carb,I mean,who actually does low GI over there these days apart from the cherub who never even says what she actually eats!

I soon found that by doing Test Test Test I built up my own personalised "Glycemic Index" which differed significantly from the "official" one. For example, wheat shot up my BG more than an equivalent quantity of any other carbs. The only thing worse was wheat mixed with other carbs. I suspect wheat germ agglutinin which affects insulin receptors. A lot of people, but not everyone, is so affected. I kearned that I can eat significant quantities of blueberries, strawberries or cherries but most other fruit was off the menu, especially bananas.

The main thing I learned was that excess carbs are toxic, and that excess varies significantly depending on time of day. When I started I was limited to about 15g at breakfast and 30g by evening. Now ten years later I do less than 10g at breakfast but I can hit 50 - 80g and sometimes 100g by evening. Not that I do this often, if I did I suspect I would bring my IR back. Was there ever anything in the GI or II or in any official diabetes guidelines about differing carb tolerance at different times of day? No, thought not.

Most Type 2s and many Type 1s have the same pattern, but paradoxically some have better carb tolerance/lower IR in the morning. I've read both that "normies" have this reverse pattern, and that they also have the same increased morning IR as "nondiabetics", which would be something well worth researching rather than dicking around with "proving" that some carbs are healthier than others.