The human body contains 55% to 78% water, depending on its size.

To function properly, the body requires between one and seven litres of water per day to avoid dehydration.

The precise amount depends on the level of activity, temperature, humidity, and other factors. Most of this food is ingested with other substances or beverages other than water directly.

It is not clear how much water intake healthy people need, though most advocates agree that a volume of about 2 litres (6-7 glasses) of water daily is the minimum to maintain proper hydration.

For those who have healthy kidneys, it is rather difficult to drink too much water, but (especially in warm humid weather and while exercising) it is dangerous to drink too little.

Alcohol and health risk

Taken in moderation, alcoholic beverages obviously meets some of the needs of water, knowing that ethanol tends to block the release of hypothalamic-pituitary anti-diuretic hormones and thus facilitate urinary loss of water. They also participate in energy intake because alcohol provides 7 Kcalories per gram.

Doses considered acceptable result from calculating the relative risk of various complications and overall mortality for the dose consumed. These risks for increase significantly for more than 4 drinks per day for men and two drinks per day for women. Lower levels of consumption are acceptable for people who wish to consume alcoholic beverages.


In previous centuries, coffee was considered a drug before becoming a common beverage; the stimulating effect of caffeine was sought for as an element of social gatherings. Tea is the most consumed beverage in the world. The only energy intake of these drinks is added sugar. The stimulatory effects of these drinks are highly variable depending on the individual.

In most studies, a moderate consumption is considered to be 2-3 cups per day. Studies have shown the discreet hypertension effect of caffeine due to the action of caffeine on mood.

Protective effects of compounds in green tea, namely antioxidants, have also been demonstrated.

Soda - General Problem of sugary drinks

These pleasure-drinks par excellence pose nutritional problems for children and adolescents who quite rightly respect health and social conventions that deny them access to alcoholic and stimulating beverages, especially when they stop being occasional fun drinks to become primary or exclusive.

For example, the CIQUAL database indicates for "Soda cola, sweet", 10.9 g carbohydrates and 44 kcal per 100 g of product (about 10% sugar!).


Taste and nutrition education in early childhood is essential to enable consumers of all ages to make an informed choice among the multitude of drinks on offer, as to the drink best suited to each circumstance – energy needs, health, pleasure or performance ...

Water should remain the only indispensable and habitual drink for all.

(Source: "Recommended dietary allowances for the French population," the CNERNA-CNRS. Edition coordinated by Ambroise Martin.)