Researchers have shown that drinking 500ml of water at half an hour before eating main meals may help obese adults to lose weight.
Obese adult participants were recruited from general practices and monitored over a 12 week period.
Each of the participants, all adults with obesity, were given a weight management consultation, where they were advised on how to adapt their lifestyle and improve their diet and levels of physical activity. 41 of those recruited were asked to preload with water, and 43 were advised to imagine that they had a full stomach before eating.
Participants were encouraged to drink tap water. Sparkling water, sodas or sweetened drinks were not allowed as part of the study.
Those in the group who were instructed to 'preload' with water lost, on average, 1.3kg (2.87lbs) more than those in the control group.
Those who reported preloading before all three main meals in the day reported a loss of 4.3kg (9.48lbs) over the 12 weeks, whereas those who only preloaded once, or not at all, only lost an average of 0.8kg (1.76lbs).
"The beauty of these findings is in the simplicity. Just drinking a pint of water, three times a day, before your main meals may help reduce your weight. When combined with brief instructions on how to increase your amount of physical activity and on a healthy diet, this seems to help people to achieve some extra weight loss – at a moderate and healthy rate. It's something that doesn't take much work to integrate into our busy everyday lives” said the author.