I have become very interested in the role that proper hydration for weight loss and the ketogenic WOE. Specifically interested in studies related to role of hydration in insulin resistance, hyperglycemia and mTOR signalling.
While I’ve found oodles of rodent studies there have also been some interesting controlled human clinical studies as well. One of these is the subject of this post:
Efficacy of Water Preloading Before Main Meals as a Strategy for Weight Loss in Primary Care Patients with Obesity: RCT
Efficacy of Water Preloading Before Main Meals.pdf (230.6 KB)
What they did: Over 12 weeks 84 patients divided into two groups with BMI’s between 33 and 36, eating a standard dietary recommendation diet (not high fat, low carb or restricted anything) did either 1.)drank 500ml (2 cups) water 30 mins before main meals (investigational group) or 2.) asked to imagine their stomachs were full 30 min prior to each meal (comparator group) and received text prompts, as did the preload group.
Neither group was informed that the trial was about water preloading and the participant information sheet informed patients that the study was concerned with two different approaches to weight loss. Neither
group was aware of what the other group was asked to do. The statistical analysis of the primary outcome was performed by an independent researcher blinded to allocation. Researchers who conducted the urine
analyses were also blinded to group allocation. The researchers who measured weight at follow-up could not be blinded to group allocation. But by then blinding really did not matter.
Result: The water drinkers lost more weight than non-water drinkers. Higher volume water drinkers (3 main meals per day) lost more weight than those drinking less than 3 meals.
What it means to me: It helps, it’s cheap, easy, could prevent dehydration and overeating. Might be a good plateau busting strategy and more importantly a weight maintenance strategy.
Maybe plateaus are really a bad spot on the continuum of adequate hydration status. When dehydrated the body holds onto everything and additional carb or calorie restriction won’t budge the needle. Maybe this process could jumpstart things.