Lecture 7- intermittent fasting

evolutionary eating patterns

food scarcity and survival, behavioral, physiological, and metabolic adaptations to food scarcity

modern eating patterns

tradition, convince, ritual, obseogenic environment

intermittent fasting 

eating patterns in which individuals go extended time periods (16–48h) with little or no energy intake, with intervening periods of normal food intake, on a recurring basis

traditional caloric restrictions 

daily energy deficit of ~500 kcals, or a 30% restriction, associated with low adherence and limited effectiveness

metabolic adaptations during IF

depletion of glycogen stores (~24hrs), decrease blood glucose (low to normal range), decrease insulin, increase glucagon, gluconeogenesis, adipose breakdown, and ketone body production

increase in cellular AMP

increases AMP-activated protein kinase, catabolic/oxidative pathways, and mitochondrial function, decreases anabolic pathways

increase in fatty acid release 

increases hepatic β-oxidation and ketone body production