Drinking a cold Coca Cola in the summer can be wonderfully refreshing, but it’s far too easy for children and teens to drink too much soda. The American Dietetic Association recommends a maximum of three 12oz cans a week. Americans are estimated to drink one 12oz can every day – but many drink much more than that, setting themselves up for major health problems.

Drinking soda has become one of the major causes of the worldwide childhood obesity epidemic, not to mention diabetes and cavities. Kids don’t realize that a 12oz can of soda contains 9 teaspoons of sugar and 140 calories. These empty calories quench your thirst, but not your appetite. What’s worse is that the sugar is usually derived from high-fructose corn syrup, an unhealthy form of sugar and an unnatural byproduct of corn.

As an example, let’s say a child drinks one or two cans a day. This extra 140-280 calories a day leads to an extra pound of permanent weight each month. In a year, your child will have gained 12 pounds of extra weight that isn’t muscle. By the time that child becomes a teen, he or she will be seriously overweight and will quite possibly have borderline diabetes or high cholesterol.

The great news is that the opposite is also true; simply cutting back on your intake of soda can easily lead to real weight loss at any age. In one study, kids who switched from soda to zero-calorie drinks lost a pound each month. However, zero-calorie drinks are still harmful to bone health and contribute to heart disease.

What can be done? First, don’t be fooled by “diet” sodas; studies show that most people do not lose weight with diet drinks, because they end up eating the same amount of food. Also, the acidic chemicals in any soda rot away your teeth’s enamel. One hundred percent juice drinks are an improvement, but they still contain a lot of sugar and are not as nutritious as the original fruit. Partial fruit juice drinks, diet drinks, and sports drinks are another notch down the nutrition scale. It’s best to stick to the basics: What can be more refreshing on a hot day than a cold glass of water, lemonade, or caffeine-free iced tea?

There really is no redeeming nutritional value to soda, and the main message of soda restriction should come from home. If parents are drinking soda throughout the day, their children will follow suit. Parents should keep their kids away from soda for as long as possible, and never keep soda at home. This may sound draconian, but it is better for your family’s health in the long run.

(This article was originally printed in Beijing Kids magazine, where I am a contributing editor. You can click here to read the rest of my BeijingKids “The Doc Is In” columns.)