So, this post will be a little out of character for me. It concerns two things that I find interesting: (1) common dates, the delicious honey-like fruit of the date palm, and staple of the Mediterranean diet, and (2) the “Glycemic Index,” which is a classification of foods based on the rate at which their Carbohydrate (i.e. sugar) content enters the bloodstream.
In case you wonder why I would care about these subjects, read my last post, on “the Zone favorable” diet system. Now, I love dates. One pitted date (about 24g) is about 2 CHO blocks in the Zone system (i.e. about 18g carbs), and it is super easy to eat. I often eat one or one half of one to quickly round out the carbs in a very high protein meal (i.e. 4 to 5 blocks). Obviously, a date is so dense and sweet, it’s going to have a high Glycemic Index, and should only be eaten in moderation.
But I was curious to know: just how bad is a date? I did an internet search, and was truly shocked! Most on-line lists of the GI of different foods report a GI for dates of “103”… which is like twice that of table sugar.
This number is super puzzling, since the USDA nutrition database records that one pitted Medjool date (24 g) has about 18g of CHO, roughly half of which are Glucose, and the other half are Fructose, and also 10% of them are fiber. Given their composition, dates SHOULD have a lower glycemic index than table sugar, not DOUBLE that of sugar.
Well, low and behold, I did some more digging and I also found a scientific paper on the subject:
This paper, by researchers from the United Arab Emirates, says that dates should be classified as low-glycemic foods, and that the commonly available commerical varieties all have GI numbers between 30 and 49.7 (three varieties are tested). These numbers are all in fact lower than sugar (58 to 65 depending on the list; compare Honey at 55).
What gives? Why is this ridiculously high number of 103 still being used on so many lists?
If anyone who reads this post cares to respond, your input would be appreciated.