Effect of Water Intake with Meals on Postprandial Plasma Glucose Levels Among Healthy College Students in Derna, Libya

Abstract

Postprandial blood glucose is an important indicator of glucose metabolism and may be influenced by dietary and behavioral factors, including the timing of water consumption in relation to meals. However, limited evidence is available regarding the effect of water intake with meals on postprandial glucose among healthy young adults. This study aimed to investigate the effect of water intake at different times in relation to meal consumption on postprandial blood glucose levels among healthy college students in Derna, Libya. An experimental study was conducted among 35 healthy college students aged 18–25 years. Participants consumed a standardized carbohydrate-containing meal under different water-intake conditions: meal alone, 500 mL of water consumed with the meal, 500 mL consumed 30 minutes before the meal, and 500 mL consumed 30 minutes after the meal, along with an additional experimental condition involving water intake. Blood glucose levels were measured at 30, 60, 90, and 120 minutes after meal consumption. Data were analyzed using SPSS version 26 with descriptive and inferential statistics, with a p-value ≤ 0.05 considered statistically significant. Blood glucose responses varied according to the timing of water consumption. The group consuming 500 mL of water with the meal showed the highest early postprandial glucose response, reaching its peak at 30 minutes, whereas the other groups generally peaked at 60 minutes. A statistically significant difference in the postprandial glucose response over time was observed between the water-with-meal group and the meal-alone group (p = 0.019). Differences among the other water-intake conditions were not statistically significant. These findings suggest that consuming 500 mL of water with a meal may influence the timing and pattern of the acute postprandial blood glucose response in healthy college students. Larger studies examining different water volumes and timing intervals, together with insulin and other metabolic markers, are recommended.