Evaluate urine osmolality as a marker of fluid intake, in healthy subjects displaying a wide range of fluid intake behaviors

Inclusion Criteria:

• Healthy female and male subjects aged 20- 30 years old (both ages included).
• BMI within the range 20-25 kg/m2 (both inclusive).
• Height within the range 1.60-1.75 m (both inclusive) for female subjects and 1.70-1.85 m (both inclusive) for male subjects.
• Monophasic contraceptive method (female subjects only)
• Smoking less than 10 cigarettes/day
• Fluid intake habits falling within one of three designated arms

Exclusion Criteria:

• Pregnant woman (as determined by a pregnancy test) or woman planning to become pregnant during the study; breast-feeding woman.
• Any clinically relevant acute or chronic diseases which could interfere with the subjects' safety during the trial, or expose them to undue risk, or which could interfere with the study objectives.
• Having participated in a clinical study for the renal diseases or having received any treatment related to the kidneys, cardiovascular disease or to hypertension in the last 12 months.