<P> One hypothesis to explain this relationship is that the phosphoric acid contained in some soft drinks (colas) displaces calcium from the bones, lowering bone density of the skeleton and leading to weakened bones, or osteoporosis . However, 2001 calcium metabolism studies by Dr. Robert Heaney suggested that the net effect of carbonated soft drinks, (including colas, which use phosphoric acid as the acidulant) on calcium excretion in urine was negligible . Heaney concluded that carbonated soft drinks, which do not contain the nutrients needed for bone health, may displace other foods which do, and that the real issue is that people who drink a lot of soft drinks also tend to have an overall diet that is low in calcium . </P> <P> A 2006 study of several thousand men and women, found that women who regularly drank cola - based sodas (three or more a day) had significantly lower bone mineral density (BMD) of ~ 4% in the hip than those who didn't, even though researchers controlled for important factors like calcium and vitamin D intake . The study also found that women who drank non-cola soft drinks didn't appear to have lower BMD and that BMD of women drinking decaffeineted cola wasn't as low as women drinking caffeinated cola sodas . The study found that the effect of regular consumption of cola sodas was not significant on men's BMD . </P> <P> In the 1950s and 1960s there were attempts in France and Japan to ban the sale of Coca - Cola as dangerous since phosphates can block calcium absorption . However, these were unsuccessful as the amounts of phosphate were shown to be too small to have a significant effect . </P> <P> The USDA's recommended daily intake (RDI) of added sugars is less than 10 teaspoons per day for a 2,000 - calorie diet . High caloric intake contributes to obesity if not balanced with exercise, with a large amount of exercise being required to offset even small but calorie - rich food and drinks . </P>

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