Milk can rehydrate active children more effectively than water or energy drinks, according to new research funded by the Dairy Farmers of Canada. The study, to be published in The Proceedings of the XXVIIth International Symposium of the European Group of Paediatric Work Physiology, claims that children consuming milk after exercise retained more fluid than those who drunk alternative beverages. Milk’s higher salt content, along with minerals, is part of the benefit, as the salt helps the body retain the fluid. As the milk also contains protein it may empty from the stomach more slowly, which would allow the body to gradually retain the fluids, rather than being “flooded” with plain water, notes the study.

Fourteen children participated in the study, with an average age of nine years. Each child repeated the exercise on three separate days, about a week apart, so that each child could try the three different drinks.

After two hours of recovery, about 75 per cent of the skimmed milk consumed was retained in the body. In comparison 60 per cent and 50 per cent of the sport drink and water consumed were retained in the body, the scientists say. Following two hours of recovery, there was twice as much urine produced with water than with skimmed milk.

The study’s findings were most relevant for children who may be playing multiple games in the same day or attending sports camps, where there is often limited time to recover before the next game or match, the researchers say.