There are actually a lot of studies supporting this idea. The problem is that, in science, one study doesn't cut it. You need lots of studies saying the same thing and then a meta analysis or a systematic review pulling them together. The only systematic review I could find was about replacing a pre-meal sugar sweetend beverage with water (resulted in significantly less calorie consumption during the meal). However, since I'm assuming that no one on here is recommending we switch to having orange juice or soda with our meals that is not very relevant.
My point is that there is much if not MORE scientific evidence that water intake assists with weight loss than there is that it doesn't. However, until someone does a systematic review on the subject we wont know for sure.
see below for the studies that I found in my 5 minutes of unsystematic searching:
http://www.nature.com/ijo/journal/va...o2012225a.html
General and Situation-specific Water
Intake Recommendations: Which Works Best
for Weight Loss?
K. Kaipainen, MSc,
[email protected], Cornell
University/VTT Technical Research Centre of Finland,
B-17 Warren Hall, Ithaca, NY 14873; B. Wansink, PhD,
Cornell University
Objective: To determine which of 2 general and situationspecific
water intake recommendations results in greatest
weight loss and who responds best to them.
Design, Setting and Participants: Voluntary participants
were recruited to the Web-based healthy eating
and weight loss program, National Mindless Eating Challenge.
Participants who returned for follow-up within 2
months after receiving one of 2 water intake recommendations,
(1) general ‘‘Drink 8 cups of water a day’’ (n ¼
93) or (2) situation-specific ‘‘Have a glass of water with
every meal and snack’’ (n ¼ 89), were included in the
analysis.
Intervention: Participants were profiled according to
an initial survey and assigned 3 targeted dietary recommendations,
with which they were instructed to comply
daily. Each month, participants were asked to complete a follow-up survey and receive a new set of recommendations.
Outcome Measures and Analysis: Weight loss outcome
was calculated from self-reported weights. Analyses
of variance and linear regression analyses were conducted
to determine participant characteristics influencing the
outcome.
Results: Situation-specific recommendation was associated
with significant weight loss (mean ¼ 0.86 lbs; standard
deviation [SD] ¼ 3.77 lbs; P ¼ .04). Situation-specific
recommendation resulted in higher weight loss among
participants whose weakness was overeating at meals
(mean ¼ 1.69 lbs; SD ¼ 3.16 lbs) than participants whose
weakness was excessive snacking (mean ¼ 0.04 lbs; SD ¼
4.02; P ¼ .04).
Conclusions and Implications: Situation-specific water
intake recommendation appears to result in weight
loss, especially among people with a tendency to overeat
at meals, presumably because water contributes to a feeling
of fullness and substitutes for more energy-rich drinks.
Dietitians can use this information to tailor their advice
accordingly.
Funding: None.