Genetic predispositions tolerance

Tolerance to the diuretic action of caffeine was demonstrated more than 50 years ago and was shown to develop on chronic caffeine intake so that the clinical significance of hypokalemia and calciuria is difficult to evaluate. Although controversial, some epidemiological studies have implicated caffeine in the increased risk for poor calcium retention. For calcium intakes lower than 750 mg per day, increased rate of bone loss and lower bone density were reported. However, it has been suggested that the effect on bone of high caffeine intake requires a genetic predisposition toward osteoporosis. In individuals who ingest calcium recommended daily allowances, there is no evidence of any effect of caffeine on bone status and calcium economy. 

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