Protein Intake Following Ultra-Processed Food Reduction in Free-Living Adults

Abstract

Ultra-processed foods (UPFs) account for a substantial proportion of energy intake and are commonly characterized by being low in protein. The growing availability of protein-fortified UPFs may contribute considerably to dietary protein intake. This study examined associations between UPF consumption and protein intake and evaluated the effects of UPF reduction on protein intake. Fifty-two healthy adults were randomized to either minimize UPF consumption (MPF; n = 25) or maintain typical dietary patterns (UPF; n = 27) for six months. Dietary intake was assessed using three-day diet records at baseline and post-intervention, and foods were classified by the Nova Food Classification System. At baseline, UPF consumption was positively associated with UPF-derived protein intake and the proportion of protein obtained from UPFs (p’s < 0.0001), while demonstrating inverse associations with protein intake relative to body mass and the percentage of calories derived from protein. The MPF group significantly reduced UPF consumption and UPF-derived protein intake (p’s < 0.0001). Despite this, total protein intake, protein intake relative to body mass, and percentage of calories derived from protein were maintained. These findings suggest that dietary protein adequacy can be preserved during UPF reduction while decreasing reliance on UPF-derived protein sources.