Diet & Kidney Stones
By Jeremy Lieb, MD
If you have ever suffered a kidney stone, you might take comfort in knowing you’re not alone in your discomfort. About one million Americans a year – or one in 300 – suffer from stones, according to the National Institutes of Health. They tend to affect men more than women, and people of ages 20 to 40 are often more prone.
So what to do to avoid this common but often painful malady? If you or a loved one has a tendency to form kidney stones, the most important step to take is simply to drink more water. This is the best and easiest way by far to reduce stone recurrence.
Another excellent preventative measure is to drink lemonade. Lemons have a high concentration of citric acid, a natural stone inhibitor.
Thirdly, a low-oxalate diet can be quite effective as well. Most stones are made of the chemical compound calcium-oxalate. The human body absorbs oxalate naturally through food and then excretes it via the urine. However, in the urine, oxalate serves as a magnet and sticks to extra calcium, thus forming kidney stones.
A diet of moderation
For repeat sufferers of kidney stones, the best proactive measure is a more controlled dietary regimen, particularly in regard to high-oxalate foods, which include:
- Berries – blackberries, strawberries, blueberries, kiwi, grapes, raspberries
- Vegetables – leafy greens, spinach, beets, quinoa, collards, okra, rhubarb
- Nuts and seeds – almond, cashews, peanuts, peanut butter
- Legumes – beans, soybeans, tofu
- The good stuff! – chocolate, beer, black tea
Notice that four of the five are otherwise healthful foods. It’s not a good idea to eliminate these from your diet but rather to moderate your intake to no more than 800 milligrams a day for men and 1,000 milligrams daily for women (1,200 after menopause). To learn more about nutritional content of almost any food, visit the U.S. Department of Agriculture’s website, where there’s an excellent database you can search.
Don’t skimp on the H2O
Most importantly – drink lots and lots of water, from eight to 13 cups a day.
With these guidelines, you can still partake in even your favorite indulgences in moderation. Recently I had a patient in my office in tears because her doctor told her not to eat any more chocolate. This list is not an ultimatum, just some guidelines.
So if you love chocolate, commit to drinking a glass of water with each chocolate bar to wash through all the oxalate. Also, vitamin B6 (pyridoxine) can reduce the amount of oxalate in your urine. Your daily multi-vitamin should contain minimum daily amounts of B6.
For additional help from your doctor, make an appointment to provide a urine specimen so that a lab can analyze your excretion. That will help your physician make better treatment recommendations.