CRYPTOQUOTE

A 2010 study from the Netherlands asked 120,852 people about their fluid intake, then followed them for 10 years. Here, neither increased water intake nor total fluid intake was correlated with a risk of fatal heart attacks or with strokes.

Then there was a 2012 study of 465 stroke patients who were followed for 17 months. It found a 27 percent decreased risk of stroke, heart attack or death among people who drank 2 or more liters of total fluid per day versus those who drank less.

As for older adults, a 2017 study assessed fluid intake among 1,055 Australian women over the age of 70, then followed them for 10 years. No association was found between death rates and either water intake or total intake of fluids.

Notably, in various other studies, higher water intake has been linked to a lower rate of kidney disease. Because kidney disease has been associated with higher rates of cardiovascular disease, this connection may be why there is less death from heart disease among people with higher fluid intake. This may be more applicable to an older population.

Of course, the amount of water you need to drink depends on losses of water from sweating or from illness and from fluid obtained via food (soups, vegetables, fruits and so on). Although the data are hardly ironclad, it seems to me that five glasses of water per day is healthy.