Kidney stones are extremely common. Many times, they are caused simply by drinking little fluids. This is probably the reason that your urologist told you to cut back on coffee, as coffee, soda, and similar beverages are all diuretics that can actually contribute to dehydration. For people who have had an episode of kidney stones, it is better to focus on drinking larger volumes of water and non-dehydrating beverages and to perform analysis of the stones and of the urine. There are several genetic dispositions to kidney stones, caused by variations in how the kidney modifies the chemical composition of the urine. Similarly, there are various chemical subtypes of kidney stones. Knowing this information can help your doctors determine whether additional medications or changes to your diet may help to prevent the formation of more stones.