Ultra-processed food intake, gut microbiome, and glucose homeostasis in mid-life adults: a controlled feeding trial
Ultra-processed food (UPF) consumption has been linked to higher risk of type 2 diabetes
(T2D), but causal evidence is limited. In this controlled feeding trial, adults (ages 40–65,
n=18) were assigned to either a high-UPF or non-UPF diet for six weeks, with diets carefully
matched for nutrients. While no significant changes were observed in insulin sensitivity,
measures of glucose control showed a trend toward worsening in the high-UPF group. No
differences were found in markers of inflammation. These preliminary findings suggest that
reducing UPF intake may help lower T2D risk, though larger studies are needed to confirm
these effects.