I think if you look into this, the calorie intake side of "it" is all derived from self-reported data from citizens. IIRC, it was phone call interviews after the fact (after a day of eating). NHANES? or something.asdf wrote: ↑Sun Dec 15, 2024 4:56 pm This is interesting.
"Since 1980, obesity prevalence among US adults has soared from 14% to 42%. The commonly accepted explanation is pervasive overeating: ever-increasing energy intake as the population gains weight, year after year. However, evidence does not support this hypothesis. National data on energy intake and energy availability show increases between 1961 and 2000, during modern industrialization of food; but a plateau or declines thereafter—even as obesity continued rising—and while physical activity modestly increased. Thus, Americans appear to be eating relatively less since 2000, for ever-increasing body sizes, as time has progressed. Although both energy intake and energy availability are measured with error, such errors would have to be new since 2000 and systematically increasing over time for these 2 separate, independent measures."
"Growing evidence suggests complex, interrelated biological interactions between food processing (including acellular nutrients, depleted prebiotics, additives), gut microbial composition and function, host metabolic expenditure, and intergenerational transmission of risk (including epigenetics, noncoding RNAs, microbial species). In this paradigm, whereas increasing energy intake may have contributed to rising obesity in earlier years, today pervasive adiposity and its physiologic adaptations have created a biological milieu which interacts with industrialized foods to promote escalating obesity, even with stable energy intake—a self-sustaining, difficult-to-reverse cycle."
https://pmc.ncbi.nlm.nih.gov/articles/PMC9170462/
People don't know what they are eating/ate, forget, don't have a sense of portion sizes, weights, fluid volumes, etc. etc. etc.