Glycemic Indexing of honey varieties

[Dane Bramage]

Glycemic Index ~> a ranking system for carbohydrates based on their effect on blood glucose levels. It compares available carbohydrates gram for gram in individual foods, providing a numerical, evidence-based index of postprandial (post-meal) glycemia.
http://www.glycemicindex.com/

There are no hits on the forum for this topic.  With diabetes essentially at epidemic levels, I would imagine it may be of interest to other beekeepers.  Leaving aside the debate on the usefulness of GI and honey vs other sweeteners, I'm specifically curious about the varying GI values among differing honey varieties. 

One study seems to indicate little to no difference, at least based on glucose/fructose ratios:
US honeys varying in glucose and fructose content elicit similar glycemic indexes.,
Ischayek JI, Kern M., Journal of American Dietetic Association 2006 Aug;106:1260-2

The predominant carbohydrates found in honey are glucose and fructose, the relative percentages of which depend largely on the floral variety. Research suggests that the fructose-to-glucose ratio in a given honey and, thus, its floral source, may influence the glycemic response and, thus, the glycemic index (GI). To date, no studies of examining the GI of US honey varieties are available. Thus the purpose of this study was to determine the GI of four US honey varieties (clover, tupelo, cotton, and buckwheat) differing in fructose-to-glucose ratio. Twelve healthy adult men and women with a mean (+/-standard error) age of 24.5+/-1.5 years served as subjects. The glycemic index of 250-mL solution servings of clover, buckwheat, cotton, and tupelo honeys providing 50 g carbohydrate were assessed relative to triplicate feedings of 50 g carbohydrate as a glucose solution. Fructose-to-glucose ratios were 1.09, 1.12, 1.03, 1.54, for clover, buckwheat, cotton, and tupelo, respectively. Blood was collected after an overnight fast and 15, 30, 45, 60, 90, and 120 minutes after intake. Ten minutes were allowed for food consumption. Areas under the glycemic response curves for each honey were expressed as percent means of each participant's average response to glucose feedings. The means (+/-standard error) of the glycemic index were 69.2+/-8.1, 73.4+/-6.4, 73.6+/-6.6, 74.1+/-8.2 for clover, buckwheat, cotton, and tupelo honeys, respectively. No statistically significant differences between the honeys were apparent, nor was a relationship between glycemic index and the fructose-to-glucose ratio detected. These results indicate that small differences in fructose-to-glucose ratios do not substantially impact honey glycemic index.

Yet another group (University of Sydney) obtained the following data:

Locust honey (Romania)                           32     
Yellow box (46% fructose) (Australia)               35
Stringy Bark (52% fructose) (Australia)           44
Red Gum (35% fructose) (Australia)               46
Iron Bark (34% fructose) (Australia)                 48
Yapunya (42 % fructose) (Australia)               52
Pure (Capilano Honey Ltd. Australia)                58
Commercial Blend (38% fructose) (WA blend)    62
Salvation Jane (32% fructose) (Australia)       64
Commercial Blend (28% fructose) (NSW blend)  72
Honey, NS(Canada)                                    87

Perhaps the GI value is not directly related to fructose/glucose ratios but something else.  32-87 is a very significant range and, although 32 is not as low as organic, raw agave (10-11) for example, it is considered "low" and could be a good thing for those who might have a need for low GI sweeteners. 

It seems the only method for obtaining GI data is a test-group in a lab/blood-test scenario.  Does anyone else know of other methods/resource?

Cheers,
Dane

[Cindi]

Dane, how cool.  You do get into some of the most interesting things.

The GI is a very important way in which we should govern which foods we intake.  I know a little bit, certainly not even enough of the GI, I should know more, and well should too.  Just some thoughts spoken out loud.  Interesting if you will receive any responses to your post.  Have a wonderful and beautiful day in our greatest of life.  Cindi

[Old Timer]

>One study seems to indicate little to no difference, at least based on glucose/fructose ratios:

I don't know about the effect glucose and fructose has on GI, but I do know that the amount of on or the other dictates how rapidly or how slowly your honey will crystallize.

[mat]

Actually, it looks directly related to fructose content. All honeys have lower GI with higher fructose content. Interestingly fructose GI is only 11. So locust honey must be very high in fructose content, and agave must be pure fructose. Ineresting data.