"The [resting metabolic rate(RMR) to lean body mass(LBM)] ratio declined significantly during the [very low calorie diet] period and decreased faster during the first week; the day 3, day 5, and day 21 ratio values were 94%, 91%, and 82%, respectively, of the original. The RMR-LBM ratio decrease after 21 d of a [very low calorie diet] was near that found in chronic under nutrition." Fricker, J., Rozen, R., Melchior, J. C., & Apfelbaum, M. (1991). Energy-metabolism adaptation in obese adults on a very-low-calorie diet. The American journal of clinical nutrition, 53(4), 826–30.
"..13 obese women during a 24-wk study. Patients were randomly assigned to a very-low-calorie diet (VLCD, 500 kcal/d) or a balanced-deficit diet (BDD, 1200 kcal/d). After 8 wk of supplemented fasting, [resting energy expenditure (REE)] of the VLCD patients decreased by 17% whereas that of the BDD patients was virtually unchanged" Fricker, J., Rozen, R., Melchior, J. C., & Apfelbaum, M. (1991). Energy-metabolism adaptation in obese adults on a very-low-calorie diet. The American journal of clinical nutrition, 53(4), 826–30.
"..prolonged semi-starvation produces significant increases in depression...most of the subjects experienced periods of severe emotional distress and depression....Participants exhibited a preoccupation with food... The participants reported a decline in concentration, comprehension and judgment capabilities...There were marked declines in physiological processes indicative of decreases in each subject’s basal metabolic rate (the energy required by the body in a state of rest), reflected in reduced body temperature, respiration and heart rate." The Biology of Human Starvation (University of Minnesota Press) 1950
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