Recently, I heard that drinking too much soda may cause health problems. It was reported that something in the soda causes a loss of phosphorous and that drinking more than two cans of soda a day could present a long-term health risk. Is this true?

Too much soda, which contains phosphorus (often listed on the ingredient label of sodas as phosphoric acid), can lower the level of calcium in the blood. This can be a problem if calcium intake is low because bone calcium is then drawn on, which over time can lead to health risks.

Your body needs phosphorus. In fact phosphorus is the second most abundant mineral in the body after calcium. The amount of phosphorus you need is set at about 800 milligrams to 1200 milligrams per day. But how much you get isn't as important as the ratio of phosphorus to calcium in your diet, which has been the subject of much recent interest. The ideal ratio of calcium to phosphorus in the diet is 1:1 and a calcium to phosphorus ratio lower than 1:2 can cause calcium to be taken from the bones in order to correct the ratio. This can lead to many of the problems of calcium deficiency, including osteoporosis.

High consumption of soft drinks (especially colas) increases phosphorus intake and may contribute to the imbalance of the calcium-phosphorus ratio. There may be up to 500 milligrams of phosphorus per serving of a soft drink, with essentially no calcium.

If you do chose to drink colas that contain phosphorus, it is important that your calcium intake is increased to match it. For example, for each cola you drink, you should have 12 ounces of milk, or take a calcium supplement that contains at least 500 milligrams of calcium.

So, you can see, the report is partially correct. To be more accurate, drinking more than two phosphorus containing sodas a day can cause long term health risks if you don't also intake adequate amounts of calcium.