It's not uncommon to see people walking around with their personal water bottles. But while many seem to have taken to the notion of drinking eight glasses of water a day, Helsinki University nutrition professor Mikael Fogelholm says most people drink more than they need to.
"The idea of constantly drinking just to be on the safe side doesn't make any sense,” he says. In Finland, it is mainly the elderly with poor eating habits who get dehydrated.
According to Fogelholm, most adults’ bodies will signal when it’s time to hydrate. However he cautions that it’s better to drink half a litre too much than too little.
To maintain fluid balance people only need to replenish the water they lose, which is about two litres every 24 hours. Fogelhom says it’s not possible to hydrate 'in advance' as the body can only handle small amounts of liquid at a time.
Fluid from food
Half of daily fluid needs are covered by food.
"At work you drink a glass of something with your meal in addition to coffee and tea throughout the day. In the morning people usually have a glass of juice and then another glass of liquid in the evening. This already adds up to one litre,” Fogelholm explains.
Today the myth that each cup of coffee must be accompanied by an equal amount of water has been busted. Coffee and tea are both considered to contribute to fluid needs.
Don't drink your calories
Many western countries urge people to curb their milk intake because of the calories, but Fogelhom disagrees and encourages people to drink skim milk, though he says water should be everyone's drink of choice.
Soda is the real problem, he says, and points out that fizzy drinks are a significant contributor to Finns' expanding waistlines.
"If you have to have a soda, make it diet," the professor says.
