When obese adults lose weight, their bodies burn more fat for energy, which lowers the respiratory quotient. Once weight loss stops and weight stabilizes, the respiratory quotient returns to its...
Mechanism
Synthesis from 1 study
When obese people eat less, their bodies burn more fat and use less energy, which lowers their respiratory quotient. When they start eating normally again, their bodies switch back to burning more carbs and using more energy, so the respiratory quotient goes back to normal — this is shown in the...
Most probable mechanism
When someone with obesity eats less, their body slows down its energy use and starts burning more fat instead of carbs, which lowers the respiratory quotient. Once they start eating normally again, their body goes back to using mostly carbs and fat like before, so the respiratory quotient returns to normal, as shown in the study with DOI 10.1016/j.ajcnut.2023.10.010.
Caloric restriction creates an energy deficit, triggering a homeostatic reduction in resting metabolic rate to conserve energy, as directly measured during weight loss in obese adults.
The reduced energy expenditure is accompanied by a shift in substrate utilization from carbohydrates to fatty acids, evidenced by a significant decrease in respiratory quotient from 0.82 to 0.76 during weight loss.
Upon cessation of energy deficit and return to energy balance during weight stabilization, metabolic rate and substrate oxidation revert to pre-weight-loss levels, restoring baseline respiratory quotient.
Evidence from Studies
Supporting (1)
Community contributions welcome
Contradicting (0)
Community contributions welcome
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.