From MedLine, a warning to women who drink cola:

October 11, 2006 — Regular consumption of carbonated cola drinks may increase risk for low bone mineral density (BMD) in women, according to the results of the Framingham Osteoporosis Study reported in the October issue of the American Journal of Clinical Nutrition. ...."Intake of cola, but not of other carbonated soft drinks, is associated with low BMD in women," the authors write. "Additional research is needed to confirm these findings.... Unless additional evidence rules out an effect, women who are concerned about osteoporosis may want to avoid the regular use of cola beverages." ....Increased cola intake has been demonstrated to reduce BMD in children, and several mechanisms may be responsible for this association. Caffeine is a defined risk factor for osteoporosis, and high fructose corn syrup may reduce bone density. In addition, colas contain phosphoric acid, which can reduce serum calcium levels and promote higher levels of parathyroid hormone. This hormone, in turn, can increase bone turnover and lead to osteoporosis.

Besides the effect on bone density as shown by this study, colas in general have chemicals in them that just do terrible damage to the body. Remember, you can literally polish chrome using Coke. Look at the ingredients listed on a soda label and ask yourself if you would ingest any of them individually.