INS and Insulin resistance: Concerns that GlcN consumption may worsen glucose tolerance and induce insulin resistance were not based on clinical observations, but on in vitro studies by Marshall et al. showing that exogenous GlcN could increase the activity of the hexosamine biosynthesis pathway, a metabolic process that is believed to function as a nutrient sensor modulating insulin sensitivity and glucose uptake in peripheral tissues 4 (Figure 1).