Increase in calciuria and oxaluria after a single chocolate bar load

Chocolate, a foodstuff rich in sucrose, fat and oxalate, is considered unsuitable in cases of obesity, diabetes mellitus, urolithiasis and postprandial hypoglycemia. However the pathophysiological effects of chocolate are poorly documented. Therefore we investigated the effects of ingestion of 100 g dark chocolate bar (45 g cocoa and 55 g sucrose) on carbohydrate, calcium and oxalate metabolisms in 10 healthy subjects. Results were compared to those of 55 g sucrose intake (control group) performed on another day. Chocolate caused i) a lesser but longer increase in plasma glucose, insulin, and C-peptide than sucrose (respectively +23% of baseline vs +60%, p < 0.001; +436% of baseline vs +755%, p < 0.01 and +200% of baseline vs +331%, p < 0.01), ii) a striking increase in triglyceridemia, calciuria and oxaluria (respectively +96%, p < 0.01; +147%, p < 0.01 and +213%, p < 0.001). Thus, chocolate (cocoa+sucrose) causes a lesser pancreatic stimulation than sucrose. However, the increases in both calciuria and oxaluria (induced respectively by sucrose and cocoa) following chocolate ingestion might contribute to urinary conditions favoring the development of calcium oxalate calculi.