Why are we talking about them? Well, for one thing, evidence exists that stones were around as long as 7000 years ago. they occur in as many as 2.6% of people. Stones of various shapes and sizes pass down the urinary tract into the bladder causing severe waves of pain. Patients experience nausea, vomiting, chills, and characteristically, it’s impossible to remain still and the patient writhes in agony. Many men say it’s the worst pain they’ve ever felt. Many women say it’s as bad as childbirth! Myth number one– the pain is due to the pressure of the stone impacting the lining of the urinary system. Wrong! The pain is actually due to urine backing up all the way into the kidneys where the nerve fibers are acutely sensitive to stretching. Once the stones pass into the bladder they pass easily and seldom cause symptoms.
How do I prevent this from happening again? They often receive a pat on the back and an answer like, “Well, Bob, or Mary, just stay away from milk and cheese.” This is a gross oversimplification of the complex field of stone prevention.
Kidney stone prevention is based on an understanding of the cause of the stone and also the importance of good hydration. There are many types of kidney stones (more than a dozen ) and not all are made of calcium. Some are due to infections or complex metabolic abnormalities. Some stones can even be caused by medicines or chemotherapy.
The basic element common to all stones is that crystalline materials precipitate (come out of dilution to form solids) whenever there is insufficient amounts of bodily fluids due to dehydration. Patients who drink at least two liters of water per day are least likely to form kidney stones. Increasing hydration does not guarantee success in stone prevention but it is the best dietary treatment by far. Water is cheap and readily available. Lowering calcium intake is in comparison a very minor factor since there is so much natural calcium in our diets. To make matters even more complicated, some rare types of stones occur in patients who are actually low in calcium? There we’ve just dispelled another myth- that lowering calcium in our diets is always the treatment of choice. Some patients receive very elaborate diets to decrease the oxalates in their diets. (calcium with oxalates together form most kidney stones). Although these patients go to great lengths to restrict the intake of rhubarb, peanuts, fruitcakes, colas, etc., they still proceed to form stone after stone. Why? The answer is that 90% of the oxalate in our bodies is a normal product of metabolism and is unaffected by diet. (No one eats much rhubarb anyway—do you?)
Have a stone work-up. This is where your urologist analyzes the stone itself (if retrieved) and analyzes your blood and urine chemistries to find out which type of stone you form and why. Then find out if dietary restrictions apply to you. Some patients may require medications.
Next, increase your fluid intake. Of course, the next question is which kind of fluid is best?
Lemonade contains six times the concentration of citrate than any other citrus juice. Citrate acts as a natural inhibitor of stones and is more powerful in preventing stones than any complicated dietary restrictions that have less impact on stone formation even when patients adhere to them faithfully. Citrate binds up the calcium and oxalates that otherwise might crystallize together inside the kidney. Citrates can also be taken as a medication prescribed by your urologist in liquid or powder form. It even comes in sugarless form for diabetics. If you hate lemonade, plain old fashioned water is the next best. The nice thing about lemonade is the convenience and the price: 50 cents a glass on the corner of your neighborhood the last time I looked.