Does water intake decrease blood glucose levels?

From the Guidelines

Drinking water is recommended to help decrease blood glucose levels, particularly in people with diabetes or high blood glucose, as it can help dilute the concentration of glucose in the bloodstream and support kidney function to remove excess glucose 1. When considering the impact of water intake on blood glucose levels, it's essential to look at the broader context of dietary recommendations for individuals with diabetes. According to the 2024 standards of care in diabetes, published in Diabetes Care 1, emphasizing key nutrition principles such as inclusion of nonstarchy vegetables, whole fruits, legumes, whole grains, nuts/seeds, and low-fat dairy products, while minimizing consumption of meat, sugar-sweetened beverages, sweets, refined grains, and ultraprocessed foods, is crucial for managing glycemia. Key points to consider include:

• Replacing sugar-sweetened beverages with water or low-calorie beverages to manage glycemia and reduce the risk for cardiometabolic disease 1.
• Emphasizing minimally processed, nutrient-dense, high-fiber sources of carbohydrate 1.
• Providing education on the glycemic impact of carbohydrate, fat, and protein tailored to an individual’s needs, insulin plan, and preferences to optimize mealtime insulin dosing 1. Overall, while water intake is an important aspect of managing blood glucose levels, it should be part of a comprehensive approach that includes a balanced diet, regular physical activity, and proper medication management, as recommended by healthcare providers 1.

From the Research

Water Intake and Blood Glucose Levels

• The relationship between water intake and blood glucose levels is complex and has been studied in various contexts 2, 3, 4, 5, 6.
• A study on the effect of immersion in Dead Sea water on glucose levels in type 2 diabetes mellitus patients found a significant reduction in blood glucose levels 2.
• However, a study on the effect of increased daily water intake on health in Japanese adults found no significant changes in fasting blood glucose levels 3.
• A review of the potential of daily water intake and its mineral nutrients in preventing and therapy of type 2 diabetes found low evidence for the positive effects of water or mineral water in improving glycemic parameters 4.
• A study on the effect of adding water to a meal on postprandial glycaemic levels in healthy subjects and type 2 diabetic patients found that water addition increased the peak blood glucose and serum insulin levels in healthy subjects and the blood glucose concentration in well-controlled diabetic patients 5.
• A study on the effect of reduced water intake on glucose regulation in patients with type 2 diabetes found that acute low water intake resulted in impaired blood glucose regulation during an oral glucose tolerance test 6.

Key Findings

• Immersion in Dead Sea water can reduce blood glucose levels in type 2 diabetes mellitus patients 2.
• Increased daily water intake may not lower fasting blood glucose levels in healthy adults 3.
• The effects of water intake on blood glucose levels may be influenced by various factors, including the type of water, the amount of water consumed, and the individual's health status 4, 5, 6.
• Reduced water intake can impair glucose regulation in patients with type 2 diabetes 6.

Study Limitations

• The studies had small sample sizes and limited durations 2, 3, 5, 6.
• The studies used different methods to assess the effect of water intake on blood glucose levels 2, 3, 4, 5, 6.
• The studies had inconsistent findings, making it difficult to draw definitive conclusions 2, 3, 4, 5, 6.