Effect of water consumption on weight loss: a systematic review

Water intake has been proposed for weight loss; however, the evidence of its efficacy is limited. The aim of this study was to systematically review the randomized clinical trials that assessed the effect of water consumption on weight with a follow up ≥ 12 weeks. A systematic query-based search was performed on PubMed, EBSCO, and Cochrane Library to identify eligible records that quantitatively measured body weight change after interventions. This review included six RCTs that reported different strategies for weight loss achievement: increasing daily water intake, replacement of caloric beverages with water, and premeal waterload. All the studies showed a weight loss effect after follow-up, ranged from -0.4 kg to -8.8 kg with a mean percentage of weight loss of 5.15%. The most effective intervention among the studies was the replacement of caloric beverages with water. The quality of the evidence for the primary outcome of weight loss was rated low to moderate. The main limitation of these results is the short-term follow up-period. In conclusion, despite 5.15% of weight loss, the low to moderate quality of evidence and the short term of follow-up are limitations to support evidence-based recommendations of water consumption for weight loss.