I don't drink soda or allow my kids to have it because I've known for years about how bad it is for teeth and bones. I know sugar is the biggest culprit, but when I tell people that the carbonation is nearly as bad because it leaches calcium from your bones, they argue with me. A friend of mine who drinks mostly plain sparkling water says I'm completely battywho's right on this?
I assume your friend thinks you're batty because of your beverage opinions and not for other reasons beyond my expertise. Given that, I'd have to side with your Perrier-drinking pal, but also assure you that it is a common misconception that carbonation pulls calcium from your bones. However, to avoid giving him more ammunition, you should probably refrain from also cautioning him against Fizzy Lifting Drinks, like those once served to an unsuspecting Grandpa Joe in a now famous chocolate factory ("Atta boy, Charlie, keep burping!").
One known effect of carbonation is that it speeds the absorption of alcohol into the blood, which makes your gin and tonic more helpful in producing a big tip for the waitress. Other than that, the bubbles are harmless. It's actually the phosphoric acid that many sodas contain, and possibly the caffeine, which have consequences for the calcium levels in the body. In general, only dark cola drinks contain both phosphoric acid and caffeine, while the iridescent green ones have just caffeine, and the clear citrus sodas and seltzers don't include either.
The negative effect of phosphoric acid on bone health is pretty well established, especially in children. Quite a bit of research has concluded that cola drinks consumed by kids seriously increase the likelihood of fractures, while consumption of non-cola carbonated beverages do not. Most of this research was done on pre-teen or teenage girls and the effect was considerable even when consumption was less than one cola per day. Toward the other end of the time-line, similar studies of postmenopausal women have almost equivalent findings. The issue of caffeine vs. calcium levels, however, is not quite so clear-cutand the stimulant may not even be a factor in kid's bone health. Some investigators have concluded that since soda often replaces milk in the child's diet, lowered calcium intake is the bigger problem.
For kids, the problem is compounded by the nearly quarter cup of sugar in a 12-oz. soda. Their teeth get a one-two punch: first an acid bath to soften up the enamel and then a nice coating of liquid sugar. Together, they make plaque bacteria happier than Star Jones on a cruise shipplenty of nooks to settle into and an all-you-can-eat buffet. In addition, as the bacteria process the sugar, even more tooth-destroying acid is produced. Soft-drink companies signing lucrative marketing contracts with financially strapped school districts, have a captive audience for their bright and shiny vending machines. It's a wonder that any teeth at all are visible in high-school graduation photos.
Certainly seltzers and sparkling waters make an excellent alternative option to sugary sodas, but more often than not, they are an acquired taste. A more palatable alternative can be natural sodas found in health food stores and some supermarkets. These drinks usually get their bite from citric or ascorbic acids rather than phosphoric acid. The major drawback to natural sodas is their sweetener, whatever the namefructose, honey, juice concentrate, rice syrup or barley maltit is still sugar and provides nothing but calories and plaque fertilizer. Diet drinks aren't much betterartificial sweeteners have their own set of issues. With compromise as a goal, a spoonful of frozen fruit juice concentrate in a glass of seltzer might keep the kids happy (and it's easier than home schooling).
I hope giving you a qualified OK for carbonated drinks opens a whole new beverage category for you. An occasional soda won't harm the kids. Just save the burping for homeroom.
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