I remember a time in the 70s and 80s when I was just getting started in the field of nutrition when fructose was considered a harmless sweetener for diabetics. Marketed as “diabetic sugar,” fructose syrup was dispensed in clear plastic containers and consumed with impunity by persons with blood sugar problems.
The embrace of fructose as an alternative to glucose was fostered by the observation that it evoked a lower blood sugar response than other sweeteners. Fructose was found to have one of the lowest glycemic index (GI) values—20, as compared to glucose, and its disaccharide maltose—100 and 105 respectively.
One putative advantage of fructose was that it seemed to get “under the radar” of the body’s insulin responses. Fructose—unlike sucrose, glucose, malt sugars and starches—not requiring insulin for its metabolism, did not appear to stoke the insulin surges which could lead to insulin resistance, a pathway to metabolic syndrome and Type 2 Diabetes.
This led the American Diabetes Association to endorse fructose as a preferable alternative to other sugars from 1979 to 2001—albeit with a caution about high intakes.
All this changed in 2004 with the publication of a landmark review—one of the most frequently cited in nutrition literature—entitled “Consumption of high-fructose corn syrup beverages may play a role in the epidemic of obesity.”