Wednesday, March 12, 2014

Lost article on insulin response to glycerine has been found!

In my previous post titled, “The poor, misunderstood...glycerol molecule,” I lamented that I was unable to find an article that would hopefully answer once and for all how insulinogenic glycerine would be for people with normal metabolisms. Googling for “Oral Glycerin Has a Negligible Effect on Plasma Glucose and Insulin in Normal Subjects” yields only references people have made to the article, but none for the article itself. There’s no record of it on the Diabetes journal website. I contacted the webmaster and they can’t find it either. I contacted the only other link I had: Dr. Thomas Wolever, MD, PhD, DM (Oxford). He was mentioned in the glycerine article by David Mendosa. Believe it or not, he responded with 30 minutes with a scan of the article. Lo and behold, he’s its author.

What’s great about this study is that it was a test of glycerine in water. There were no fat sources that would blunt the insulin response. I think it’s pretty clear from this test that glycerin is most likely nothing to worry about as far a low carb dieting is concerned. It would be nice to repeat this experiment with people who are insulin resistant. Anyone up for a N=1 study?

Here’s a reprint of the elusive article:

Oral Glycerin Has a Negligible Effect on Plasma Glucose and Insulin in Normal Subjects

THOMAS M. S. WOLEVER. Toronto, ON, Canada

Glycerin is consumed by humans in foods and medicines, but its effects on blood glucose and insulin are not known. Thus, to determine the effect of glycerin on plasma glucose and insulin responses, 8 healthy subjects (5 male, 3 female; age 27.3±1.7y; BMI 23.9±1.3kg/m2) were studied on 6 mornings after 10-14h overnight fasts. They drank 250ml aqueous solutions containing glycerin (15, 35 or 75g) or glucose (15 or 75g) or water alone, with blood samples taken fasting and at 1/4, 1/2, 3/4, 1, 2 and 3h. All test drinks were well tolerated, except, after 75g glycerol, 4 subjects experienced mild nausea or headache which resolved by the end of the test session. Oral glucose elicited a significant dose-dependent increase in the incremental areas under the glucose and insulin response curves (AUC). However, after oral glycerin, plasma glucose and insulin responses did not differ significantly from those after water alone (Figure).

It is concluded that doses of oral glycerin up to 75g have a negligible effect on postprandial plasma glucose and insulin concentrations, and that doses up to 35g are well tolerated by healthy humans.


  1. Great find, Gerard!, if only we didn't need a $300 ice cream maker :)

    1. Technically you can make ice cream with a ziplock baggie, but the results aren't as professional.