Ultra-processed foods and health: are we correctly interpreting the available evidence?

Several studies have linked adverse health effects to the consumption of ultra-processed foods (UPF) according to the NOVA classification. However, whether the consumption of UPF is the actual causal factor for such health outcomes is still unknown. Indeed, different groups of UPF examined in the same epidemiologic study often show markedly different associations with the occurrence of the health endpoints. In this Comment, we discuss some such studies and point out that the available evidence on how different UPFs have been associated with health, as well as the results of studies examining specific food additives, call into question the possibility that ultra-processing per se is the real culprit. It is possible that other unaccounted for confounding factors play an important role. Future, urgently needed studies will clarify this issue.