A new study shows kidney stones are on the rise. What is surprising to doctors is not only the number of new cases of kidney stones, but that they are also developing in people who are not normally considered high risk, including children, women and African Americans.

Kidney stone statistics:

  • Kidney stones are one of the most common disorders of the urinary tract.
  • Each year in the United States, people make more than a million visits to health care providers and more than 300,000 people go to emergency rooms for kidney stone problems.
  • Kidney stones affect 19 percent of men and 9 percent of women by age 70.
  • In a study done between 1997 and 2012, the frequency of kidney stones increased by 16 percent.
  • More women under the age of 25 experience kidney stones than men.

What is a kidney stone?
Kidney stones are small, hard, crystallized deposits that are made up of mineral and acid salts which form inside your kidneys. Our urine excretes waste which is comprised of various chemicals including calcium, oxalate, urate, cysteine, xanthine and phosphate. When urine is too concentrated, meaning there is too much waste and too little liquid, crystals begin to develop. Gradually, the crystals can conjoin and form a large, solid stone.

What causes kidney stones?
There is no single cause for kidney stones, and often, there is no known cause. However, there are in fact many different types of kidney stones which can help determine the cause. For example, calcium kidney stones are the most common form of kidney stone. Oxalate kidney stones are made up of oxalate, which is a naturally occurring substance in food. Therefore, anything that increases oxalate levels can increase the risk of a kidney stone. And uric acid stones often form in people who do not drink enough fluids or eat a diet high in protein.

How are they treated? 
The treatment for kidney stones usually depends on the size of the stone. If a kidney stone is smaller than four millimeters in diameter, a person can usually pass the stone through the urine on their own. Drinking lots of water (at least two to three quarts a day) and taking over-the-counter pain relievers can help when passing small stones. Larger stones are more difficult to pass and may require a more invasive treatment such as surgery or shock-wave lithotripsy. Shock-wave lithotripsy involves high-energy sound waves that break up the stone in to more easily passable pieces.

Who is at risk?
The risk factors for kidney stones include being over age 40, being male, ingesting too little water, too much/little exercise, obesity, weight loss surgery, digestive diseases, and consuming a diet high in salt, protein or sugar -- especially fructose. Having a family history of kidney stones can also increase your risk of developing them; furthermore, if you have already experienced kidney stones, you are at an increased risk of developing more.

How can I prevent kidney stones?
The best way to prevent kidney stones is through making dietary changes. It is important to always drink lots of water, at least six to eight glasses a day. This can significantly reduce your risk of developing kidney stones. Make sure you don’t hold in your urine -- it is recommended to excrete about 2.6 quarts of urine every day. Eat less foods that are rich in oxalate such chocolate, soy products, okra, beets, sweet potatoes, tea and nuts. Also, eat less foods that are high in salt and animal protein.
 

Dr. Samadi is a board-certified urologic oncologist trained in open and traditional and laparoscopic surgery and is an expert in robotic prostate surgery. He is chairman of urology, chief of robotic surgery at Lenox Hill Hospital and professor of urology at Hofstra North Shore-LIJ School of Medicine. He is a medical correspondent for the Fox News Channel's Medical A-Team and the chief medical correspondent for am970 in New York City. Learn more at roboticoncology.com. Visit Dr. Samadi's blog at SamadiMD.com. Follow Dr. Samadi on Twitter and Facebook.