Drinking Water Ups Resting Energy Expenditure by 25%

TEL HASHOMER, IsraelOverweight children who drink 10ml kg1  of cold water increase their resting energy expenditure (REE) by 25% for more than 40 minutes, according to a new study published in the International Journal of Obesity. The findings suggest drinking water may assist overweight children in weight loss or maintenance, and may warrant emphasis in dietary guidelines against the obesity epidemic.

Israeli researchers studied 21 overweight, otherwise-healthy children (age 9.9±1.4 years, 11 males) who drank 10ml kg1  of cold water (4°C). REE was measured before and after water ingestion for 66 minutes. The main outcome measure was the change in mean REE from baseline values.

Immediately after drinking water, there was a transient decrease in REE, from a baseline value of 3.32±1.15kilojoule (kJ) per minute to 2.56±0.66kJ per minute at minute 3 (P=0.005). A subsequent rise in REE was then observed, which was significantly higher than baseline after 24minutes (3.89±0.78kJ/min (P=0.021)), and at most time points thereafter. Maximal mean REE values were seen at 57minutes after water drinking (4.16±1.43kJ per min (P=0.004), which were 25 higher than baseline. REE was significantly correlated with age, height, weight and fat-free mass; the correlations with maximal REE values after water drinking were stronger than with baseline REE values.

The researchers concluded consuming the recommended daily amount of water for children could result in an energy expenditure equivalent to an additional weight loss of about 1.2kg per year, which reinforces the concept of water-induced REE elevation shown in adults.