BOSTON -- In 2002, professor Heinz Valtin, MD, at Dartmouth Medical School published an article stating that with all the water we get in food and various beverages, simply drinking when thirsty is more than enough for healthy adults who aren't engaging in vigorous exercise.

In their newly published book YOU, THE OWNER'S MANUAL, Doctors Roizen and Oz say that it's essential to keep your body hydrated with sixty-four ounces (that's 8 glasses) of water a day. So, what's a person to believe?

Maybe a little common sense is necessary when thinking this one through. First of all, water is a natural lubricant for your body. It makes everything operate more smoothly. It keeps you looking good (great for your skin) and helps eliminate toxins from your body.

In the high temperatures and humidity of Florida, whether exercising or not, we lose fluid and are at greater risk for dehydration.

When this happens, we can fatigue more easily, get headaches, as well as lose coordination skills.

It’s also very easy to over estimate how much water we drink. Try drinking from a bottle that you can carry with you during the day and keep track of how often you fill it up (if at all)! Experiment and take note of how you feel. After all, you know the most about YOU. More than likely you will find that that magic formula of the recommended 8 glasses of water a day is right on -- especially during the summer months.