Hydration and Weight Loss


Living in the desert we have all been told or at least thought that we should drink more water. The body needs water for almost every function it has. Even when exhaling, there is a loss of about 2 cups of water a day in the form of vapor. Besides knowing that water intake is important, did you know that increased hydration could lead to fat loss? A study done in 2010 compared two groups that followed the same diet, but one of the groups consumed 500ml of water (about 2 cups) before meals. The water group had around a 5 pound weight loss compared to the group that just changed their diet (Dennis, 2010). So, how does staying hydrated increase weight loss?

How Water Facilitates Weight Loss

One mechanism by which this works is through water’s ability to induce a feeling of fullness. When the stomach starts to fill up it releases chemicals letting the brain know that it is filling up and therefore initiating a feeling of fullness. This works in the same way as eating, but you’re replacing food with calorie free water. If one of the issues you’re having is not knowing when to stop eating; a glass or two of water before and throughout the meal can help curve your appetite. Drinking water can also be a solution if you’re like me and tend to eat out of boredom. Water will give you something to preoccupy yourself with while becoming full in the process.

Another way fat is lost from water intake is through a process known as water-induced thermogenesis. One study showed that increasing water intake by the previously stated amount of 2 cups pre-meal has shown to increase metabolic rate by 30% (Boschmann, et al, 2003). This increase in energy is not only needed to process all of the water, but to warm up the water as well. From that reasoning there has also been evidence that cold water is more beneficial for weight loss, because it requires more energy to heat the water up to the required temperature.

How to Hydrate

Besides drinking two cups before and during meals it is also important to continue hydrating throughout the day. It’s also important to state that this applies directly to water. Not any liquid such as soda or juice would count towards this goal, because the sugar content will not illicit the same results as strictly water ingestion. It’s also important to limit caffeine intake. Since caffeine is a diuretic there might actually be more water loss. Drinking a cup of coffee isn’t going to ruin the goal of fat loss through proper hydration, but we don’t recommend continuously ingesting caffeine throughout the day. Hopefully with the increase in water you will feel more energetic and will not need caffeine in the first place.


  1. Michael Boschmann, Jochen Steiniger, Uta Hille, Jens Tank, Frauke Adams, Arya M. Sharma, Susanne Klaus, Friedrich C. Luft, Jens Jordan; Water-Induced Thermogenesis.2003; 88 (12): 6015-6019. doi: 10.1210/jc.2003-030780
  2. Dennis, E. A., Dengo, A. L., Comber, D. L., Flack, K. D., Savla, J., Davy, K. P., & Davy, B. M. (2010). Water Consumption Increases Weight Loss During a Hypocaloric Diet Intervention in Middle-aged and Older adults.Obesity (Silver Spring, Md.)18(2), 300–307. http://doi.org/10.1038/oby.2009.235