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5 Ways to Prevent Kidney Stones


Anyone who has suffered a kidney stone will do anything to prevent a recurrence. After enduring one New Year’s Day and three subsequent surgeries, I was especially anxious to have a nephrologist review the results of a 24-hour urine collection that provided a snapshot into my diet.

A nephrologist, like a urologist, is a kidney doctor. Urologists perform surgery. Nephrologists help you avoid needing such services.

As a triathlete, fitness enthusiast and someone downright OCD when it comes to diet, I figured I’d be the last person to come down with a kidney stone. By undergoing the lab work, I’ve been able to get a handle on five key strategies:

1. Watch the Oxalate

Many healthy foods that have long been part of my diet—spinach, nuts, berries, as well as chocolate—are high in oxalate, the metabolism byproduct that contributes to kidney stone formation. Most stones, like mine, are calcium oxalate. My levels of oxalate urine and calcium oxalate fell outside the danger zone.

2. Eat More Citrus

Citrus fruits, including lemons, help fight kidney stone formation. Living in Florida, I’m a big citrus fruit eater and have added lemon juice to my diet since having the stone. The test results showed that my citrate urine was 879 mg per day on a scale where anything over 320 is considered good.

3. Hold the Salt

Too much salt promotes kidney stone formation since the kidneys tend to retain the salt and dump stone-causing calcium into the urine. Even if you don’t add salt to food, it’s already in everything, especially in restaurant food. I was pleased to find that my sodium urine was in the safe zone.

4. Eat Less Protein

The influence of 1980s bodybuilding culture is still felt in the fitness industry, where many men believe it’s impossible to consume too much protein. Actually, that’s a very dangerous thing since animal protein is metabolized to oxalate.

From mid-2009 through the end of 2010, I drank post-workout recovery shakes consisting of four scoops of whey protein—or 120 grams of protein. I threw a fifth scoop on my morning oatmeal. That alone is nearly double the daily protein allowance for a 167-pound person, even an active person like myself. (It’s better to go with a balanced post-workout recovery mix that has 30 grams or less of protein.)

After getting a kidney stone, I cut the whey by 90 percent. My uric acid urine, which reflects protein consumption, still clocked in at 1,026 mg/day. A good level is considered 700 or below. High uric acid is associated with kidney stones and gout. My phosphorus urine, another reflection of animal protein consumption, also was 30 percent too high.

“You’re still eating way too much protein,” said Prakas D’Cunha, my nephrologist. I protested that I slashed the whey protein and rarely eat red meat, just a lot of chicken and fish. Bottom line: I have to continue to watch the protein.

5. Drink More Water

Dr. D’Cunha’s bigger concern was my water consumption, which was producing just 1.9 liters of urine a day. That sounds like a lot—almost a 2-liter bottle—but two liters is the minimum someone should be producing. A Florida-based triathlete should be drinking more and producing more urine. To produce two liters of urine, you need to drink at least three liters, more if you’re training and sweating out a lot of fluid.

“Not drinking enough water increases all of your other risk factors,” says David Goldfarb, a New York nephrologist who I’ve corresponded with throughout this saga. “On the other hand, drinking a lot of water trumps everything else.”

About The Author

Pete Williams – Pete Williams is a contributing writer for CorePerformance.com and the co-author of the Core Performance book series.

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Tags: Health, Disease