It seems the common “8x8 rule” for hydration is in for some rethinking.

The long-accepted conventional wisdom is to prevent dehydration, a person needs to drink adequate amounts of water in temperate climates. Health authorities in the West commonly recommend drinking eight 8 ounce (237 ml) glasses a day. That’s some 2 liters or half a gallon. This is the so-called 8×8 rule and it’s tantamount to the gold standard in hydration.

Now, there is an increasing clamor for doubling that amount to 16 eight ounce glasses a day for a total of one gallon (3.8l) on the argument this increased intake is healthier. Will people have the stomach for this much water every day?

Two studies show that drinking 17 ounces (500 ml) of water can temporarily boost metabolism by 24 percent to 30 percent. But this doesn’t seem to be enough for some health fanatics who believe a person needs to drink water constantly throughout the day, even when he’s not thirsty.

This argument, facetious as it may seem, is about the right amount of hydration (if there is such a thing) people need daily. It all boils down to water balance.

Yes, water is essential for vital functions like transporting oxygen to your cells and regulating body temperature. And, yes, staying hydrated is critical.

But it’s plainly obvious hydration needs are highly individual, so the same recommendations can’t be applied to everyone.This means the 8x8 rul will be good for some people while the more challenging 16x8 might be good for others.

Just remember the golden rule of hydration: drink when you feel thirsty and stop when your thirst is quenched. Since people are physically different and have different states of health, metabolism and mental outlook, the “When to Start,” and “When to Stop” drinking arguments become a matter of personal choice.

The proponents of the 8x8 rule can take heart from research, however limited, showing that drinking more than your hydration requirements benefits your health.

Doctors say most adults not engaged in exercise sufficiently meet their fluid needs by letting thirst be their guide. There are as yet no specific recommendations on how many glasses of water most adults should drink per day.

But, for those who really need some authoritative source, let the recommendations for total water intake of the Institute of Medicine (IOM) be their guide.

IOM suggests most women meet their hydration needs when consuming 78 ounces (2.3 liters) of total water per day from both beverages and food. Most men can meet their hydration needs when consuming 112 ounces (3.3 liters) total water per day, which is close to one gallon.