Weight loss effects of water

The apparent weight loss effects of water have been subject to some scientific research.

This evidence has been used by some of the scientists who worked on this research, and by others, to bolster suggestions that people who are trying to lose weight can benefit from augmenting – but not replacing – their dietary programs by drinking water, either before meals or at any time. Such advice had previously been given by dietitians even before the most recent research was published.

There is some evidence drinking water before or during a meal may help aid weight loss when used in conjunction with a calorie-controlled diet.

Drinking water prior to each meal may help in appetite suppression. A promising approach to reducing appetite which does not involve taking any drugs, and is very safe, is to drink circa 4-5 dl of water 30 minutes before a meal. Though this had been a folk remedy for overeating for many years, and is recommended by some dietitians and stipulated in some scientific studies, it was only recently that the approach was subjected to a scientific randomised controlled trial to see how much effect it had:

Thermoregulation is the process that allows the human body to maintain its core internal temperature. Cold induced thermoregulation has been proven to be a successful weight loss experiment. One study found that drinking 500 ml of water increased metabolic rate by 30% after 30-40 min with a total thermogenic response of 100 kJ (24 kcal). About 40% of the thermogenic effect originated from warming the water from 22 to 37 °C. However, a later study in 2006 states that approximately 500 mL 3 °C cold water caused only increase in energy expenditure by 4.5% for 60 minutes.

Some people prefer carbonated water to still water, and may find it easier to increase their water intake via consuming more carbonated water, rather than by consuming more still water. One study states that consumers of carbonated water prepared at home had significantly higher mean drinking water intake (tap + bottled + carbonated water) in percentage of total water intake than non-consumers, and lower mean intakes of milk, bottled water and tap water, respectively.

Water is essential to maintain all the normal functions of the mammalian body including controlling body temperature through sweating, lubricate and cushion joints, carry nutrients and oxygen to cells and keeping the blood stream liquid enough to flow through the blood vessels.

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Wikipedia