Household food insecurity refers to experiencing or worrying about lacking sufficient money to buy safe, nutritious, socially- and culturally-appropriate foods for all members of a household. It may function as an indicator of perceived and real environmental uncertainty. Evolutionary life history theory holds that exposure to increased environmental uncertainty will be associated with changes in time and energy allocations in physiology (e.g. fat storage), psychology (e.g. food preferences), and behaviour (e.g. eating behaviours). Specifically, the so-called “insurance hypothesis” predicts that uncertain conditions, especially regarding the nutritional environment, will drive increased investment in tissues, thought patterns, and behaviours that will increase chances of survival and reproduction in the face of a sudden, unanticipated energy shortfall. In practice, this means: an increased tendency to store energy in adipose tissue, an increased tendency to worry about food shortages and increased preferences for energy-dense foods (e.g. sugar), and an increased tendency to consume energy-dense foods. The evidence regarding the insurance hypothesis in contemporary human populations, however, is mixed. This talk presents new, cross-national comparative analyses (mixed effects trend analysis regressions) pertaining to the insurance hypothesis, using publicly-available data on observation years 2016-2023 from 42 high income countries . The simplest models show that: 1) changes in household food insecurity prevalence are temporally related to external sources of uncertainty (e.g. economic and geopolitical shocks), supporting the idea that food insecurity serves as an indicator of environmental uncertainty; and 2) changes in annual consumption of an energy-dense, shelf-stable foodstuff (candy/ confection) is temporally associated with changes in household food insecurity prevalence. However, more complex modelling approaches which take account of phylogenetic and geographic distance among countries are needed before we can claim that there are grounds to reject a null or stochastic relationship between changes in dietary behaviours and changes in environmental uncertainty as measured via household food insecurity.