Water is essential to human life and adequate hydration can be a useful weapon in your weight loss arsenal. Susan Kleiner wrote in "The Journal of the American Dietetic Association" that the average adult male needs 12 cups of fluid each day to stay hydrated and the average adult female needs nine cups. That's before you add in fluid replacement for exercise or the water you lose on hot days even when you think you aren't sweating.
Before Meals
A 2009 study led by Elizabeth Dennis in "Obesity," as well as others, found that overweight and obese subjects who drank 500 mL -- or about 16.9 fluid oz. -- of water before each meal in addition to adopting a reduced calorie diet lost an average of 2 kg -- or 4.4 lbs. -- more body weight over a 12-week period than subjects who were merely eating a reduced calorie diet.
Throughout the Day
If you keep a bottle of water handy throughout the day and drink continuously, you will not only help prevent the negative effects of dehydration, you will be better able to resist unhealthy snack foods or sugary beverages. People often mistake thirst for hunger and reach for food they don't need to quench it. A good way to test that you truly are hungry is to first drink a glass or two of water and wait 20 minutes. If you are still hungry after 20 minutes, then you can sit down to a healthy meal or snack.
Dehydration
A 2003 article in the "European Journal of Clinical Nutrition" states that even mild dehydration decreases your mental alertness and ability to concentrate. You will feel more tired and less able to exercise if you are dehydrated. There is also a relationship between mild dehydration and a higher incidence of several types of cancer and heart disease, although not enough research has been done to establish a causal link.
Fluid Requirements
Dietitians recommend that you get a minimum of 30 mL of fluid per kilogram of body weight each day. That means that a 180 lb. person -- who weighs about 82 kg -- needs a minimum of 2,455 mL of fluid each day. That's a little more than 10 cups. Not all of your fluid requirements have to be met by drinking water, because you will get around three to five cups of fluid from the food that you eat -- depending on your specific eating habits. Exercisers or people in warm climates must drink extra fluids, however, to compensate for excess fluid losses. Fluid losses during exercise are highly individualized, but you can develop a rehydration program for yourself by weighing yourself before and after exercise. Drink throughout your workout and drink an additional 16 to 24 fluid oz. of water or sports beverage after your workout for every pound you lost. If you lost one or more pounds during your training session, increase the amount of fluid you consume during your next training to try and maintain your weight from pre-workout to post.
References
- "The Journal of the American Dietetic Association"; Water: An Essential But Overlooked Nutrient; Susan Kleiner; February 1999
- "The Journal of the American Dietetic Association"; Water Consumption Reduces Energy Intake at a Breakfast Meal in Obese Older Adults; Brenda Davy, et al.; October 2007
- "Obesity"; Water Consumption Increases Weight Loss During a Hypocaloric Diet Intervention in Middle-aged and Older Adults; Elizabeth Dennis, et al.; August 2009
- "European Journal of Clinical Nutrition"; Impact of Mild Dehydration on Wellness and on Exercise Performance; R. J. Maughan; 2003
- American Council on Exercise; Healthy Hydration
Member Comments