Research

Energy balance

During short-term caloric restriction (800 kcal/day), switching from a standard mixed diet to a ketogenic diet increases the rate of total weight loss solely through increased water excretion, with no significant difference in the rate of fat loss between the two diets.

If you are trying to lose fat, the speed at which you lose fat is determined by your calorie deficit, not whether you eat carbs or not. A ketogenic diet might make the scale drop faster initially due to water loss, but you are not burning fat faster than if you ate a standard low-calorie diet. Focus on maintaining your calorie deficit consistently.

GoodRefutesHIGH confidence
Discrepancies in rate of weight loss induced by ketogenic vs. nonketogenic isocaloric regimens result almost entirely from differences in water balance. Rate of fat loss is a function of degree of energy deficit.
M U Yang et al. · Journal of Clinical Investigation · 1976

Why this rating

Controlled metabolic ward study with energy-nitrogen balance method, though limited to 10-day periods and obese males.

Source

Composition of weight lost during short-term weight reduction. Metabolic responses of obese subjects to starvation and low-calorie ketogenic and nonketogenic diets.

M U Yang et al. · Journal of Clinical Investigation · 1976

DOI 10.1172/jci108519

rct · n=6Cited 180×
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DOI resolved against Crossref · corpus check 2026-06-10

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