Drinking water is often applied as a dietary means for weight loss and overweight/obesity prevention, but no evidence-based recommendation exists for this indication.
Dr Rebecca Muckelbauer and colleagues from Germany summarized the existing evidence on the association between water consumption and body weight outcomes in adults of any body weight status.
In a systematic review, the team retrieved studies from 4 electronic databases (MEDLINE, EMBASE, CINAHL, and COCHRANE), cross-references by PubMed functions and hand-searching, and experts’ recommendations.
Any type of study including adults aged more than 18 years that reported the association between daily water consumption and any weight-related outcome, such as body weight, body mass index, or body weight classifications, was eligible.
The researchers retrieved 4963 records, 11 original studies and 2 systematic reviews were included.
|Studies of individuals dieting for weight loss or maintenance suggest a weight-reducing effect |
|American Journal of Clinical Nutrition|
In participants dieting for weight loss or maintenance, a randomized controlled trial, a nonrandomized controlled trial, and an observational longitudinal study showed that increased water consumption, in addition to a program for weight loss or maintenance, reduced body weight after 3–12 months compared with such a program alone.
The team found that In mixed-weight populations not primarily dieting for weight loss or maintenance, 2 short-term randomized trials showed no effect of water consumption on body weight, and 6 cross-sectional studies showed inconsistent results.
Dr Muckelbauer's team concludes, "Studies of individuals dieting for weight loss or maintenance suggest a weight-reducing effect of increased water consumption, whereas studies in general mixed-weight populations yielded inconsistent results."
"The evidence for this association is still low, mostly because of the lack of good-quality studies."