Comments on OBESITY PANACEA: Drinking water prior to meals enhances weight-loss...

@ Sigrid, In response to your first question, tha...

2009-12-01T09:29:08.082-05:00

@ Sigrid,

In response to your first question, that is exactly right - drinking water helped people consume less calories. Although both groups were aiming at 1,500 calories for men, they were still free-living, so there was naturally some variability in the amount of calories that people consumed (according to diet records the water group averaged 1,454 kcal/day, while the non-water group averaged 1,511). In other words, if you want to go on a reduced calorie diet, consuming more water seems to help.

As for the meta-analysis you describe, it actually wasn't looking at water as a weight loss aid. It was examining whether there was a scientific rationale behind the "8 glasses of water per day" message, which has never been targeted at weight loss. So while 8 glasses of water per day may not have much science behind it, drinking a glass or two of water before a meal does.

Sorry for being late, just discovered your site. ...

2009-12-01T07:42:08.247-05:00

Sorry for being late, just discovered your site.

Just wondering: If they were on a fixed-calorie diet how could drinking water influence their intake? 1200 calories is 1200 calories. If drinking water before every meal led to decreased food consumption this would mean they ate less than their 1200 calories, wouldn't it?

And do you have other sources for drinking water as a fat-loss-aid? There was this meta-study by Heinz Valtin ( http://calorielab.com/news/2006/05/28/8-glasses-of-water-a-diet-urban-legend/ ) who couldn't find any reliable studies backing up this theory.

Drinking 500 ml water did have a significant reduc...

2009-08-31T07:00:43.240-04:00

Drinking 500 ml water did have a significant reduction on energy intake pre-trial. After twelve weeks this effect was gone. The watergroup did loose more weight and more rapidly, so the conclusion is that it works for the first couple of kilo's.

The other interesting fact is the age of the population. We're talking senior citizens. The watertrick does not seem to have an effect on younger people(Walleghen EL van 2007).

The suggestion that temperature has een effect, might be true. But at least on calorie expenditure. If you have one liter of water in the fridge at 7 degrees celsius and you would drink it. The body will warm it up to core temperature (37 degrees). Since a calorie is the amount of energy necessary to heat 1 gram of water 1 degree Celsius, it will burn 30 calories in the process, which is nothing but a funny thought.

In practical sense drinking water before a meal will help seniors loose weight more rapidly in the first couple of weeks. Putting the water in the fridge will add another 45 calories per day (three meals). Since senior citizens tend to drink less often (because they are less mobile), it is a good behaviour pattern to learn. Don't expect anything from younger people.

@ Todd - Yes, I have heard that before as well - t...

2009-08-24T19:42:31.094-04:00

@ Todd - Yes, I have heard that before as well - the notion that you should drink water along with your meal to help enhance fullness earlier in the meal. Apparently, this is not always the case. I am unsure if there has been any comparison of fullness with different timing of water intake in other studies.

@ darya - I agree, and I often have the same experience. I also used to drink tons of juice when thirsty - of course never considering the liquid calories I was consuming when I was simply dehydrated, not necessarily hungry.

Thanks for spreading the news:)

@ Anonymous That is quite an interesting suggestion. This study didn't consider water temperature as a potential confounder, but it is rather intriguing to think cold water may be more effective. I do remember reading somwhere that you tend to drink less when the liquid is cold - sort of more thirst quenching when cold - this could actually mean that it would be more effective using room temp water as you could drink more and fill up.

Peter

Or you could try the physicist's diet.

I discovered why fashionistas rave about drinking gallons of water a couple of years ago, when I had cystitis - once I got up to 3l/day I didn't want to eat at all. Not fun though.

Cool story. I definitely find that sometimes I thi...

2009-08-24T17:51:19.777-04:00

Cool story. I definitely find that sometimes I think I'm hungry when I'm really just thirsty. Will share this with my readers :)

Interesting. I think Barbara Rolls says in "...

2009-08-24T14:14:00.074-04:00

Interesting. I think Barbara Rolls says in "Volumetrics" that the liquid may not help if it is taken separately, at least based on triggering satiety mehanisms. She might have been too conservative? It sounds like it still has at least some satiation effect.