Are sports drinks okay for my eight-year-old son?

The question

The answer

If your son is involved in a vigorous physical activity that lasts longer than one hour, a sports drink can be beneficial. Drinks such as Gatorade and PowerAde provide fluid and electrolytes (sodium, potassium, chloride) lost through sweat during prolonged exercise. While some are sugar-free, most contain carbohydrates in the form of liquid sugar and/or high-fructose corn syrup to provide energy for working muscles.

While they may help hydrate your son during a long soccer match, they're not necessary. Kids can get all the nutrients and hydration they need by eating healthy foods and drinking water before, during and after exercise. If you decide to let your son have a sports drink during or after prolonged exercise, limit him to an eight-ounce serving. Kids shouldn't drink more than eight ounces of any sugary drink, even if they are very active.

Kids should not consume sports drinks with meals or just because they're thirsty. One of the biggest concerns is that if sports drinks replace good sources of calcium in the diet, such as milk or soy beverages, kids won't get the calcium and vitamin D their bones need during rapid growth.

Sports drinks contain calories, too, and can increase the risk of excess weight gain — which can be a problem for sedentary kids. Guzzling sports drinks outside of exercise will also boost a child's intake of sodium and refined sugar. Prolonged consumption has also been linked to tooth erosion.

Bottom line: If your son is a sports drink fan, reserve them for prolonged exercise and keep his portion size to eight ounces.

Send dietitian Leslie Beck your questions at dietitian@globeandmail.com. He will answer select questions, which could appear in The Globe and Mail and/or on The Globe and Mail website. Your name will not be published if your question is chosen.

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