OK, I've found my source. In this quite old interview with philosopher Stefan Molyneux, Pr. Lustig argued that fructose acts very similarly to ethanol at the metabolic and cellular level, contributing to issues like fatty liver, triglyceride production, and even addictive properties... It's a great and relatively short episode in which they both discuss Pr. Lustig's article, "The Fructose Epidemic"

Also, it's important to note that we're talking about fructose, which is present in the food etc, and not glucose. Both are metabolised differently by the body.