How does drinking water help you lose weight
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How Drinking Water Helps You Lose Weight
Increased Water Consumption and Weight Loss
Water and Weight Loss in Dieting Adults
Drinking water has been shown to aid weight loss, particularly in individuals who are actively dieting. Studies indicate that increased water consumption, when combined with a weight loss or maintenance program, can lead to a significant reduction in body weight over a period of 3 to 12 months1. This effect is more pronounced in those who are following a structured diet plan, suggesting that water can enhance the effectiveness of dietary interventions1 4.
Replacing Caloric Beverages with Water
One of the most effective strategies for weight loss is replacing caloric beverages, such as sugary drinks and diet beverages, with water. This substitution not only reduces overall calorie intake but also promotes greater fat oxidation, as water does not stimulate insulin production3 5. Clinical trials have demonstrated that individuals who replace diet beverages with water experience greater weight loss and improvements in insulin resistance over both short-term and long-term periods3 6.
Water Intake and Energy Intake Reduction
Drinking water before meals can help reduce total energy intake. This is because water can create a sense of fullness, leading to reduced food consumption during meals. Studies have shown that premeal water consumption can result in a modest but significant reduction in body weight4. This strategy is particularly effective when water is consumed instead of caloric beverages, which often contribute to excess calorie intake without providing satiety5.
Long-Term Benefits of Increased Water Intake
Sustained Weight Loss and Maintenance
Long-term studies have found that increased water intake is associated with sustained weight loss and better weight maintenance. For instance, replacing diet beverages with water over an 18-month period resulted in greater weight reduction and improved metabolic health markers, such as insulin resistance and postprandial glucose levels6. This suggests that water can play a crucial role in maintaining weight loss over extended periods.
Reduced Risk of Weight Gain
In free-living populations, higher water consumption has been linked to a lower risk of weight gain. Prospective cohort studies have shown that each additional cup of water consumed per day is associated with a small but significant reduction in weight gain over four-year intervals9. Replacing sugar-sweetened beverages with water can further amplify this effect, leading to even greater reductions in weight gain9.
Water Consumption and Body Composition
Impact on Body Fat and Waist Circumference
Higher water intake is also associated with favorable changes in body composition. Studies have found that increased consumption of drinking water and food moisture is linked to lower body fat percentages and reduced waist circumference7. These findings suggest that water not only helps with weight loss but also contributes to healthier body fat distribution.
Water and Metabolic Health
In addition to aiding weight loss, drinking water can improve various aspects of metabolic health. Increased water intake has been associated with lower fasting insulin levels and better insulin sensitivity, which are important factors in preventing and managing obesity-related conditions3 6. These metabolic benefits further support the role of water in a comprehensive weight management strategy.
Conclusion
Drinking water can significantly aid in weight loss and weight maintenance, especially when it replaces caloric beverages and is consumed as part of a structured diet plan. The benefits of increased water intake include reduced energy intake, greater fat oxidation, improved metabolic health, and favorable changes in body composition. While more high-quality studies are needed to strengthen the evidence base, current research strongly supports the recommendation of drinking water for effective weight management.
Sources and full results
Most relevant research papers on this topic
Association between water consumption and body weight outcomes: a systematic review.
Increased water consumption may have a weight-reducing effect in individuals dieting for weight loss or maintenance, but the evidence for this association is low and inconsistent in general mixed-weight populations.
Systematic Review
Very Rigorous Journal
Highly CitedDrinking Water Is Associated With Weight Loss in Overweight Dieting Women Independent of Diet and Activity
Drinking water may promote weight loss in overweight dieting women by lowering total energy intake and altering metabolism, but long-term effects remain unclear.
Very Rigorous JournalHighly CitedEffects on weight loss in adults of replacing diet beverages with water during a hypoenergetic diet: a randomized, 24-wk clinical trial.
Replacing diet beverages with water after the main meal may lead to greater weight reduction and improve insulin resistance during a weight-loss program.
RCTVery Rigorous JournalEffect of water consumption on weight loss: a systematic review.
Water consumption can lead to 5.15% weight loss, but the quality of evidence and short follow-up period limit its use for evidence-based recommendations.
Systematic ReviewDrinking Water and Weight Management
Drinking water reduces total energy intake and increases fat oxidation, potentially aiding in weight management and obesity prevention.
Literature ReviewEffects of replacing diet beverages with water on weight loss and weight maintenance: 18-month follow-up, randomized clinical trial
Replacing diet beverages with water after meals in women may lead to further weight reduction and improved carbohydrate metabolism over a 12-month weight maintenance program.
RCTVery Rigorous JournalCross-sectional association of dietary water intakes and sources, and adiposity: National Adult Nutrition Survey, the Republic of Ireland
Higher consumption of drinking water and food moisture, but not total water or beverage moisture, is associated with lower BMI, body fat, and waist circumference, independent of energy intake and expenditure.
Observational Study
Rigorous JournalEffects of Advice to Drink 8 Cups of Water per Day in Adolescents With Overweight or Obesity: A Randomized Clinical Trial
Adolescents with overweight or obesity who were advised to consume 8 cups of water per day did not experience a significant change in body weight, despite intensive behavioral supports.
RCTVery Rigorous JournalChanges in water and beverage intake and long-term weight changes: results from three prospective cohort studies
Increasing water intake and replacing sugar-sweetened beverages with water is associated with lower long-term weight gain.
Meta-AnalysisVery Rigorous JournalHighly CitedAssociation between water consumption and body weight outcomes in children and adolescents: A systematic review
Water consumption in children and adolescents is associated with reduced body weight outcomes, but more research is needed to confirm this recommendation.
Systematic ReviewRigorous Journal