Can You Trust the Glycemic Index?
The short answer is ‘doubtful’.
You’ve probably seen the books – where the words ‘revolutionary’ ‘new’ and ‘glycemic index’ all appear in the same sentence.
Lets get something clear from the outset. Nutritional research institutes around the world are populated by people who either have short memories or are too young to know just how old this concept is.
The glycemic index is definitely not new, it’s as old as the hills. If you don’t believe me, search on the internet for William Banting’s letter on corpulence, dated 1864.
www.thefitblog.net/ebooks/LetterOnCorpulence/LetteronCorpulence.pdf
It’s also stretching the definition of the word to say that the glycemic index is ‘revolutionary’.
All of the popular ‘low carb’ diets are, in essence, low glycemic index diets – meat-fish-chicken etc, combined with low energy-dense carbohydrates, particularly vegetables (excluding peas, pumpkin, potato and corn) and to a lesser degree fruit. It’s all about eating from the top of the Hourglass.
The Glycemic Sideshow
As I see it, there are several reasons to suggest that the GI model, (concept or theory) about how to eat wisely is a side show.
The first and most significant reason is that the glycemic index bar has been set too high. The ‘Official’ standard for the glycemic index is
- low GI is less than 55
- medium GI is 56 – 69
- high GI is 70 or more
Hourglass Diet Guide To The Glycemic Index
| Less than 30 | Low | |
| 30 – 40 | Moderate | |
| 40 – 50 | Medium | |
| 50 – 60 | High | |
| 60 + | Very High |
The problem with the ‘official’ standard, (and I’m not sure who’s in charge of setting the standard) is that if ‘low GI’ is good, then ‘medium GI’ is not bad, which means that the current rash of glycemic index books read like an apology for industries that refine cereals into manufactured food – bread, pasta, breakfast biscuits, white rice …, and foods with added sugar.
It’s a last ditch attempt to make manufactured, cereal-based foods appear respectable. The dieticians should be moving heaven and earth to steer people away from eating anything that comes in a cardboard box or a plastic bag. This glycemic nonsense is encouraging people to eat junk food.
One of the reasons for the success of the low-carb diets is that they recognise that eating foods with a GI of lower than 30 not only helps people to lose weight but also helps to get the right balance between insulin which stimulates the production of fat and glucagon which stimulates fat loss.
The best book for this is Protein Power by Michael and Mary Eade.The GI concept doesn’t make a clear enough the distinction between eating fresh food and junk food. Fresh food should always take precedence over junk food. As it stands a handful of peanut M&M’s (33) look a better food choice than a handful of raisins (64).
If you read the tables you’ll find that confectionery rears its ugly head in the list of GI foods between 40 and 50. It’s junk. It’s the fat content that’s lowering the GI.
You can’t cloak the junk food wolf with the sheep’s skin of GI respectability. There have to be questions asked about the desirability of various foods, regardless of their GI. Not to do so gives some people the impression that some of the ‘low GI’ foods are good for them, when they’re patently not.
Anyone for a block of chocolate (43), a bag of corn chips (42) and a Coke (53)?