How alcohol increases food consumption.
What the evidence says
- The effect sits above a threshold rather than rising across the range. `cal02` gave 12 men 0, 1 unit (8 g ethanol) or 4 units (32 g) thirty minutes before an ad libitum lunch; intake was significantly higher after 4 units (5786±991 kJ) than after 1 (4928±1245 kJ), and the paper states the finding as holding "above a certain threshold"[1]
- Alcohol taken before a meal increases what is then eaten — at four units in `cal02`'s test, and as a general tendency in Yeomans' review[1],[2]
- Two routes are offered, and they come from different sources: appetite stimulation, with hunger rated higher after 4 units while fullness was unchanged, and impaired inhibitory control over eating[1],[2]
- One unit did not produce the effect. The moderate case is the condition `cal02` tested and excluded — and Yeomans' review reports that moderate consumption may protect against obesity, particularly in women[1],[2]
- The short-term and long-term evidence disagree, and the review says so plainly: laboratory data show over-consumption while long-term epidemiology shows no clear positive association for moderate drinkers. The review calls this puzzling and leaves it open, offering adaptation of energy balance and altered nutrient partitioning as possible explanations[2]
- Energy consumed as alcohol is additive to dietary energy — alcohol calories are not compensated for, leading to passive over-consumption[2]
- In mice, ethanol activates hypothalamic Agrp neurons, which are "normally activated by starvation", and the authors find that it can "paradoxically sustain brain starvation signals" and drive overeating despite caloric sufficiency (corrected 2026-09-10 from "normally only activated by starvation" and "creating false starvation signals"; the authors' own phrase is "false 'starvation alarms'")[3]