ROX_TENSIO18 is a randomised cross-over trial and the main objective is to evaluate the effect of daily consumption of sodium bicarbonate water for 15 days on blood pressure.

Secondary objective are:

• Evaluation of the effect of daily consumption of sodium bicarbonate water on total salt intake
• Evaluation on blood pressure of the usual food groups that are the strongest contributors of salt intake.

Volunteers are normotensive subjects divided into two equivalent groups. Group A subjects will begin their first 15-day period with the consumption of St-Yorre mineral water.

Group B will begin the first 15-day period by drinking tap water. After a washout period of 15 days, each group alternates with a new period of 15 days of water consumption monitoring: tap water for group A and mineral water St-Yorre for group B.

For each period salt intake and blood pressure are measured.Three-day food records are also performed for both 15-days periods.

Inclusion Criteria:

• Normal blood pressure between 90/60 and 140/90 mm Hg
• Usually drinks tap water;
• Knowing read and write French routinely,
• Possessing an internet connection at home,
• Possessing and knowing how to use a computer or tablet,
• Affiliated with a social security scheme
• Not Trust
• Having signed the informed consent letter

Exclusion Criteria:

• Pregnant or lactating woman
• BMI greater than 35 kg / m²
• Heart failure
• History of cardiovascular disease
• Hypertension treated or untreated
• Renal failure.