Factors that impact kidney stone size can include not drinking enough fluids, a poor diet, certain supplements, excess calcium and oxalate, and infections such as urinary tract infections. One of the most common factors that increases kidney stone size is a lack of fluids entering and leaving the body, which causes dehydration. Dehydration may result from excess sweating during exercise or hot weather, as well as from caffeinated or alcoholic drinks. The kidneys use fluids to wash away acids and excess minerals, and when not enough fluids are present, those substances remain in the body. The formation of kidney stones begins when those acids and minerals begin to lock onto each other.
There are different types of kidney stones, including calcium oxalate, struvite, uric acid and cystine. The most common type is the calcium oxalate stone, which forms as a result of excess calcium and oxalates in the body. Calcium can build up as a result of consuming too many calcium-rich foods, as well as from taking high doses of supplements such as vitamin D, which increases the absorption of calcium. Oxalate levels can rise as a result of consuming excess amounts of oxalate-rich foods such as spinach, rhubarb, celery, beans, sweet potatoes and strawberries.
Struvite stones are usually the result of a urinary tract infection. These can often become quite large, quite quickly. Uric acid stones are often the result of a high-protein diet containing lots of red meat and other animal proteins. These proteins cause the acid levels to rise within the body and, eventually, they bond with other substances to increase the kidney stone size. Cystine kidney stones are caused when cystine, an amino acid, builds up and bonds with other substances; cystine kidney stones are rare, but they often run in families.
A kidney stone may be as small as a grain of sand or as large as a golf ball. When not enough fluids are present to wash them out, the kidney stone size will continue to increase. A smaller stone is much easier to pass than a large kidney stone, because treating small kidney stones can usually be done by consuming plenty of fluids and taking certain pain medications to help ease the discomfort. Treating large kidney stones is more difficult, because they are unable to pass through the system on their own. A doctor may perform surgery, use a ureteroscope to pull it out, or use a machine to send shock waves at the stone, which breaks it into smaller pieces that are easier to pass.