Drink the glass, then wait fifteen minutes

For some of the people here, yes; for others, no; and the argument crosses three conversations on one side and four on the other, so it is rendered below with both sides. Thirteen separate conversations say a large glass before eating fills the stomach, shrinks the portion and stops the overeating. Against it: two conversations say the water fools the stomach for the length of the meal and then leaves you feeling starved and eating more later, and one account puts the fullness at twenty to thirty minutes; two say liquid does nothing for their appetite at all; two accounts in one exchange say they can drink a great deal and remain hungry, to which the answer given is that the trick might only work for people who were thirsty and thought they were hungry. One correction says the research that made this famous was actually about starting a meal with a low-calorie soup, and that water was tested afterwards and did less; another account says their doctor told them water around meals speeds the stomach’s emptying and brings the hunger back sooner; two cautions say the stomach stretches and wants more water for the same effect over time; one correction says the claim that it is a standard military tactic is false. Outside these conversations there is one trial to name, and it is small: in a US obesity journal in 2010, forty-eight adults aged fifty-five to seventy-five who were already on a reduced-calorie diet were split, and the half who drank half a litre before each meal lost roughly two-fifths more weight over twelve weeks than the half who did not. That is one study, in older adults, on a diet — it does not settle the exchange below, and this page does not pretend it does. Single-conversation exchanges elsewhere run one account to four, one to five and three to four against the trick, and four to two for the warnings over the benefits.

Telling thirst from hunger, the people here say, and the fifteen minutes is the tool. Three separate conversations drink a glass when hunger arrives between meals and wait; two more put the wait at fifteen minutes and say that either the urge has gone — it was thirst — or it is still there and you eat something. One account says a lot of the people who overeat are also short of water, which is carried here as one account’s view and not a fact. One exchange, two accounts each way, is whether the glass works at all, and the accounts’ decider is exactly this: whether the feeling was thirst. Two single accounts warn that water on an empty stomach makes them hungrier, not less — one says it wakes the digestion up — and one exchange runs two accounts to one on that. So the accounts’ version of the tip is not ‘drink to eat less’ but ‘drink to find out’, and the finding out costs a quarter of an hour.

Five separate conversations say it does — bloating, indigestion, gas — and two corrections in these conversations say the mechanism is a myth: plain water has almost no power to change the acidity of the stomach, two accounts say, and another simply calls the belief wrong. The exchange crosses conversations, two accounts on two sides against three on three, and does not settle; single-conversation versions run one account to four against the water. The accounts’ decider is your own gut: several accounts get heartburn or wind from a large glass before eating, one account’s doctor advised a gap of twenty minutes before and an hour after meals, and one exchange, one account each way, is whether to drink right before or wait half an hour after. One account sips lukewarm water twenty minutes after a meal instead and says it settles things. The argument in these conversations is about comfort and about a mechanism the corrections reject, not about danger. One correction from a different corner of these conversations is worth keeping beside this: cooked rice does not swell in the stomach when you drink after it — it is already cooked — so the discomfort one account describes is volume, not expansion.

Less than you have been told, and far less than some accounts here drank. One correction, backed by two accounts, says the eight-glasses-a-day rule traces to research from the 1940s and that the body regulates its water through thirst and the water in food; another says there is no evidence that forcing water beyond thirst does anything except send you to the bathroom. For a figure with a source: the NHS says to aim for six to eight cups or glasses of fluid a day. On the other side is the warning from the safety line: four cautions rated high, from several conversations, say that large volumes in a short time can dilute the blood’s salt dangerously — one account describes a hospital stay — and one account’s ceiling is under a litre an hour unless you are sweating hard. Two accounts say they physically cannot drink two glasses at once, and one says forcing it makes them sick; one caution says a lot of water at once brings loose stools. On fizzy water: one account swore it fills you more, and one correction answers that carbonation stretches the stomach over time — which is why it is discouraged after stomach surgery — and works against the point. So the accounts’ own answer to ‘how much before a meal’ is that there is no agreed number — the conversations range from a glass to a bottle and never settle it — and this page names that as a gap rather than inventing one.

Anyone for whom eating is a battleground, first — the safety line above is theirs and the accounts say so twice. Four separate conversations say that eating past fullness driven by feelings, or to the point of self-loathing, is not a stomach-capacity problem and will not answer to a glass of water; one caution says the help there is therapy or retraining, and one account says their depression sends them toward food, the opposite of every trick here. One contraindication says none of this is for anyone underweight, and one caution says assuming someone is heavy because they overeat ignores the rest of their life. And one paragraph for a different reader entirely: two conversations use water to stretch a small food supply further because there is not enough food, and three accounts say the whole premise of three meals a day does not fit their lives; that is a money page, not this one, and this site’s page on asking the stall for the seconds is nearer to it. What the accounts do instead of the glass: start the meal with a low-calorie soup, which one correction says is the version the research supports; eat slowly and chew, which is this site’s page on putting the fork down; brush your teeth after the last meal, which three accounts say ends the evening’s eating — and three others say makes them hungrier or just gives the ice cream a mint flavour; chew gum, which one exchange, two accounts to one, says stirs the appetite rather than kills it, and one correction says two big-name gums are not sugar-free; or eat a small real thing — nuts, an apple, milk — which one exchange, one account to four, prefers to any trick. Two conversations say tracking what you eat is more direct than any trick, and one caution says tracking can turn obsessive and sour your relationship with food. Three corrections tidy the surrounding folk wisdom: meal timing does not decide weight, total intake does, though one account says timing helps with hunger; fewer larger meals were more satisfying than many small ones in the research one account cites; and one account links a study finding that metabolism does not slow appreciably between twenty and sixty. Fasting appears in two conversations as the thing that worked for some accounts; it is carried here as their experience only, with the caution from another that it is not doctor-recommended for everyone. What the accounts did not provide, and the page names as gaps: how much water before a meal, whether the trick reduces what you eat over a day or only delays it, and where healthy fullness management ends and restriction begins — the last is the safety line’s question, and a GP’s.