Kidney stones? I feel your pain

By Jeff Pavelka, D.O., family medicine, Providence Medical Group-Happy Valley

It’s shocking how much agony a tiny crystal of salt and minerals can cause when it’s trying to work its way through your urinary tract. Women describe the pain as similar to childbirth. Men say it’s the worst pain they’ve experienced. 

If you’ve had a kidney stone, you’ll do just about anything to make sure you never have one again. Prevention is especially important, because once you’ve had one, you’re 10 times more likely to have another one. 

Prevention is also important for people with diabetes or gout, people who are obese and people who’ve had gastric bypass surgery. All of these conditions increase the risk of kidney stones. Family history is a factor, too, so people with close relatives who’ve had kidney stones need to be extra careful. 

If you’ve been lucky enough to avoid kidney stones, whether or not you have a condition that puts you at higher risk, you still might want to practice a little prevention to make sure you keep up that lucky streak. 

Save yourself a world of hurt

Kidney stones are formed when the natural composition of urine – mostly water, salts and minerals – is out of balance. That’s why people with the conditions mentioned above are at higher risk – their urine tends to be more acidic. The most common cause of urinary imbalance, however, is not a medical condition – it’s simply drinking too little water. 

To prevent kidney stones and the pain that comes along with them, the most important thing you can do is to drink more fluids. About two liters a day is a good goal for most people. While water is your kidneys’ favorite drink, research has shown that caffeinated beverages also decrease the risk of stones. It’s not clear whether it’s the caffeine that’s making the difference, or whether people who drink caffeinated beverages just drink more fluids in general. In any case, drinking caffeinated coffee, tea and diet soda is associated with lower risk. The opposite is true for sodas and drinks that contain sucrose or fructose – these sugars can increase the risk of kidney stones. 

Here are some other things you can do to reduce your risk:

  • Pay attention to the color of your urine. If it’s clear or very light, like a light beer or watered-down lemonade, you are well hydrated. If it’s darker than that, you’re not drinking enough water and you’re putting yourself at risk of a kidney stone.
  • Don’t go overboard on salt, which hides in many canned, boxed and restaurant foods. About 2,000 mg of sodium per day is a safe threshold. 
  • Take it easy on spinach and rhubarb – these foods contain a chemical called oxalate, which increases the formation of calcium oxalate stones, the most common kind of kidney stones.
  • Limit soft drinks, candies and other foods and drinks that contain sucrose and fructose. These simple sugars make you more likely to form calcium oxalate stones.
  • Pay attention to the amount of calcium in your daily supplements. Supplementing with up to 2,000 mg of calcium per day is good and may lower your risk of kidney stones, but taking more than that can raise your risk.
  • Avoid very high doses of vitamin C – again, 2,000 mg a day is a good upper limit. Anything that makes your urine more acidic (pH less than 7) can increase your risk of kidney stones. If you’re curious, over-the-counter kits are available to check the pH of your urine.
  • Reduce the amount of animal protein in your diet – high amounts of meat, eggs, cheese, milk and yogurt can lead to kidney stones.
  • Eat more vegetables and fruits.
  • Include moderate amounts of high-fiber foods like whole grains and bran, legumes, cabbage and carrots – they can help you stay regular and avoid constipation, which can make a difference. Beware of mega fiber supplements like Phytate, however – they can sometimes increase kidney stone formation.
  • Do get some regular activity, but if you exercise for more than 40 minutes a day, pay very close attention to your hydration. Marathon runners and other athletes are more likely to become dehydrated and, as a result, to form kidney stones.

Think you have a kidney stone? See your doctor

If you experience an unusual, cramping pain in your side or on one side of your lower back, or if you notice blood in your urine, see a doctor. These are the most common signs of a kidney stone. If tests confirm that you have a kidney stone, your doctor will recommend that you strain your urine through cheesecloth or a coffee filter to try to catch the stone when it passes out of your urethra. If you can catch the stone, or even a few tiny specks of the crystal, your doctor can send it to a lab for analysis to find out whether it’s made of calcium oxalate, calcium phosphate or uric acid. This is a very important step, because once you know what type of stone you tend to form, your doctor can recommend more specific dietary changes to reduce the chances that you’ll form a stone in the future.

Unfortunately, most kidney stones do need to pass out of your body through your urethra, and that is not a comfortable process. But if you’re in a lot of pain and the stone doesn’t seem to be passing, ask your doctor about medications that can help. Flomax can dilate the ureter and urethra to help the stone pass more easily. Other medications can help with pain, or with reducing recurrent stones. If your stone is too large to pass – generally anything larger than 10 mm – a urologist may need to explore other ways to remove the stone. 

One in 11 people at some point in their life will have a kidney stone, but research suggests that we could cut that rate in half if people hydrated adequately and followed the other dietary recommendations for prevention. Going through the experience of passing a kidney stone just once is a powerful motivator to give that a good try.

Health Library:

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Holistic Prevention