Research

Hormonal

Early time-restricted feeding (eTRF) reduces appetite and increases fat oxidation but does not significantly alter 24-hour energy expenditure in humans.

If you try eating all your meals between 8 am and 2 pm, you likely won't burn significantly more calories than usual. However, you will likely feel less hungry and more full throughout the day because your hunger hormones (ghrelin) are better regulated. This makes it easier to eat less without feeling deprived, which is the actual mechanism for weight loss.

GoodQualifiesHIGH confidence
eTRF did not affect 24-hour energy expenditure (Δ = 10 ± 16 kcal/d; P = 0.55). Despite the longer daily fast (intermittent fasting), eTRF decreased mean ghrelin levels by 32 ± 10 pg/mL (P = 0.006), made hunger more even-keeled (P = 0.006), and tended to increase fullness (P = 0.06-0.10) and decrease the desire to eat (P = 0.08). eTRF also increased metabolic flexibility (P = 0.0006) and decreased the 24-hour nonprotein respiratory quotient (Δ = −0.021 ± 0.010; P = 0.05).
Éric Ravussin et al. · Obesity · 2019

Why this rating

Randomized crossover trial with matched food intake, though small sample size (n=11).

Source

Early Time‐Restricted Feeding Reduces Appetite and Increases Fat Oxidation But Does Not Affect Energy Expenditure in Humans

Éric Ravussin et al. · Obesity · 2019

DOI 10.1002/oby.22518

crossover · n=11Cited 300×
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DOI resolved against Crossref · corpus check 2026-06-10

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