Wine versus ethanol in human nutrition. III. Calcium, phosphorous, and magnesium balance

A metabolic balance study was performed to determine the effects of wine vs ethanol on absorption of various elements. Calcium, phosphorus, and magnesium data are reported here. The study was divided into four 18-day experimental periods during which six healthy males were given, in random order, 1 liter/day of one of the following test beverages: Zinfandel wine (9.3% w/v alcohol); delacholized Zinfandel wine; pure ethanol (9.3% w/v aqueous solution); or deionized water. The test beverages were administered along with a controlled isocaloric diet in four equal feedings over a 12-hr period. Each man served as his own control. Urinary calcium and magnesium did not change appreciably during the course of the study. Urinary phosphorous, however, was significantly greater during wine and ethanol administration, suggesting that alcohol may affect the metabolism or renal tubular reabsorption of this element. Despite considerable individual variation, the data showed that wine and dealcoholized wine enhanced absorption of calcium, phosphorus, and magnesium. This apparently was due to an effect of one or more of the many congeners present in wine and absent in a calorically equivalent amount of pure ethanol. The natural acidity of wine also may have played a role in creating a more favorable intraluminal environment for absorption. There was no significant difference between experimental periods in serum calcium, phosphorus, and magnesium.