we included 3,615 french men and women , aged 3065 years , with baseline fasting glycemia ( fg ) < 6.1 mmol / l , who participated in the 9-year follow - up d.e.s.i.r . participants provided written informed consent , and the protocol was approved by the ethics committee of bictre hospital , kremlin - bictre , france . incident hyperglycemia was identified by an fg 6.1 mmol / l or treatment for diabetes , and incident diabetes was identified by an fg 7.0 mmol / l or treatment of diabetes during at least one of the three follow - up examinations ( years 3 , 6 , and 9 ) . smoking , dietary habits , degree of physical activity , and alcohol consumption were assessed using a self - administered questionnaire . mean daily intake of water , wine , beer or cider , and sweet beverages was categorized in the questionnaire into six mutually exclusive levels : none , < 0.5 , 0.5 to 1 , 1 to 1.5 , 1.5 to 2.0 , and > 2 l. in the present analyses , the levels were grouped into three classes : < 0.5 , 0.5 to 1 , and > 1 l. other clinical and biological measurements are presented in the supplementary methods . results are presented as means ( sd ) or median ( 25th75th percentiles ) for quantitative variables and as percentages for qualitative variables . baseline means and percentages were compared between the three w - intake classes using anova or  tests . logistic regression models were used to determine odds ratios ( ors ) and 95% cis corresponding to the comparison of incident hyperglycemia in middle and high classes of w - intake in comparison with the lowest class . adjustment variables were either known risk factors for type 2 diabetes or factors associated ( p < 0.10 ) with hyperglycemia and w - intake in our population . we included 3,615 french men and women , aged 3065 years , with baseline fasting glycemia ( fg ) < 6.1 mmol / l , who participated in the 9-year follow - up d.e.s.i.r . participants provided written informed consent , and the protocol was approved by the ethics committee of bictre hospital , kremlin - bictre , france . incident hyperglycemia was identified by an fg 6.1 mmol / l or treatment for diabetes , and incident diabetes was identified by an fg 7.0 mmol / l or treatment of diabetes during at least one of the three follow - up examinations ( years 3 , 6 , and 9 ) . smoking , dietary habits , degree of physical activity , and alcohol consumption were assessed using a self - administered questionnaire . mean daily intake of water , wine , beer or cider , and sweet beverages was categorized in the questionnaire into six mutually exclusive levels : none , < 0.5 , 0.5 to 1 , 1 to 1.5 , 1.5 to 2.0 , and > 2 l. in the present analyses , the levels were grouped into three classes : < 0.5 , 0.5 to 1 , and > 1 l. other clinical and biological measurements are presented in the supplementary methods . results are presented as means ( sd ) or median ( 25th75th percentiles ) for quantitative variables and as percentages for qualitative variables . baseline means and percentages were compared between the three w - intake classes using anova or  tests . logistic regression models were used to determine odds ratios ( ors ) and 95% cis corresponding to the comparison of incident hyperglycemia in middle and high classes of w - intake in comparison with the lowest class . adjustment variables were either known risk factors for type 2 diabetes or factors associated ( p < 0.10 ) with hyperglycemia and w - intake in our population . baseline characteristics of the 3,615 normoglycemic participants are presented according to their class of w - intake ( table 1 ) . among them , during follow - up , 565 subjects became hyperglycemic and 202 developed diabetes . the daily w - intake was negatively associated with the risk of new - onset hyperglycemia , even after adjustment for multiple metabolic risk factors . compared with daily w - intake of < 0.5 l , ors were 0.64 ( 95% ci 0.490.83 ) and 0.73 ( 0.550.97 ) for classes of 0.51.0 l and > 1.0 l , respectively ( p = 0.003 ) . after further adjustments for intake of other beverages , the ors were slightly attenuated : 0.68 ( 0.520.89 ) and 0.79 ( 0.591.05 ) for classes of 0.51.0 l and > 1.0 l , respectively ( p = 0.016 ) ( table 1 ) . with the two upper classes combined , the or was 0.72 ( 0.560.92 ) ( supplementary fig . 1 ) . there was no interaction with several important characteristics , including those related to self - reported alcohol or tobacco consumption ( supplementary table 1 ) . baseline characteristics of the study population and risk for new - onset hyperglycemia during follow - up , by classes of mean daily w - intake data are means ( sd ) or medians ( 25th75th percentiles ) for continuous variables and percentages of patients for categorical variables . thzd , thiazidic diuretics ; furo , furosemide ; homa - ir , homeostatic model assessment index of insulin resistance ; homa - b , homeostatic model assessment index of insulin secretion . hypertension was defined as systolic or diastolic blood pressure > 140 or 90 , respectively , or treated with antihypertensive drugs . ors ( 95% cis ) for the association between daily w - intake at baseline and the risk of incident hyperglycemia ( fasting plasma glucose 6.1 mmol / l or treatment for diabetes ) are presented according to two statistical models ; variables for adjustment were either known risk factors for type 2 diabetes or factors associated ( p < 0.10 ) with hyperglycemia and w - intake in our population . model 1 : adjusted for age , sex , bmi , baseline fg , physical activity , smoking status , triglycerides , homa - ir , and total cholesterol . model 2 : further adjusted on self - reported intake of other fluids ( i.e. , volumes of beer or cider , sweet drinks , and wine consumed per day ) . the c - reactive protein was available for only 181 , 466 , and 333 subjects in the three classes of w - intake , respectively . * * hdl cholesterol and ldl cholesterol were not available for 28 and 26 subjects , respectively . the same trend , although nonsignificant , was observed for the association with new - onset diabetes : compared with participants with a daily w - intake < 0.5 l , ors for those drinking 0.51.0 l and > 1.0 l water per day were 0.68 ( 95% ci 0.411.15 ) and 0.75 ( 0.431.32 ) , respectively , p = 0.36 . risk for hyperglycemia was negatively and independently related with self - reported w - intake in normoglycemic middle - aged individuals from the french general population however , the association was moderately attenuated when important metabolic risk factors and potential confounders were introduced as covariables in the analysis , including intake of other classes of beverages with known adverse long - term effects ( sweet and alcohol - containing drinks ) . our data support the novel idea that vasopressin , besides its role in urine concentration , is also an important actor in glucose homeostasis ( 1 ) . the negative association of w - intake and risk for hyperglycemia was relevant among many subsets of participants , and those reporting a low w - intake ( < 0.5 l ) had a higher risk for hyperglycemia ( for example , participants in the high physical activity group ) ( supplementary table 1 ) . this indicates that identification of individuals with a w - intake of < 0.5 l may be widely relevant to target preventive interventions regarding the metabolic risk . diabetes incidence was low and statistical power was thus limited ; 24-h urine volume was not measured , but the urinary density was inversely associated with self - reported w - intake , arguing for the validity of the questionnaire ( table 1 ) . in addition , we can not exclude residual confounding : healthier behaviors correlating with higher water drinking could account for the observed association . finally , only volunteers were included and the results may not be extrapolated to the general population . knowing the rise of vasopressin in diabetes , its effect on glycemia , gluconeogenesis , and glucagon release , it is surprising that no attention had been given to vasopressin as a possible risk factor for hyperglycemia and diabetes until a recent report of an association between copeptin and the incidence of diabetes ( 1,4,5,14 ) . our study extends this observation , drawing attention to a low w - intake as a possible new risk factor for impaired glycemia . it suggests that an increase in w - intake , an easy and costless intervention , could prevent or delay the onset of hyperglycemia and subsequent diabetes . hopefully , our study will serve as a benchmark to design appropriate clinical trials testing the efficacy of this intervention in people who report drinking < 0.5 l of water per day , as did almost 20% of the participants in this cohort .
objectivewater intake alters vasopressin secretion . 
 recent findings reveal an independent association between plasma copeptin , a surrogate for vasopressin , and risk of diabetes.research design and methodsparticipants were 3,615 middle - aged men and women , with normal baseline fasting glycemia ( fg ) , who were recruited in a 9-year follow - up study . 
 odds ratios ( ors ) and 95% cis for the incidence of hyperglycemia ( fg 6.1 
 mmol / l or treatment for diabetes ) were calculated according to daily water intake classes based on a self - administered questionnaire.resultsduring follow - up , there were 565 incident cases of hyperglycemia . after adjustment for confounding factors , ors ( 95% cis ) for hyperglycemia associated with classes of water intake ( < 0.5 l , n = 677 ; 0.5 to < 1.0 
 l , n = 1,754 ; and > 1.0 l , n = 1,184 ) were 1.00 , 0.68 ( 0.520.89 ) , and 0.79 ( 0.591.05 ) , respectively ( p = 0.016).conclusionsself - reported water intake was inversely and independently associated with the risk of developing hyperglycemia .