Preventing Kidney Stones

I’ve never had kidney stones, but I’ve heard people describe the pain of passing them as akin to pulling your upper lip over the back of your head. (Or maybe that was a description of childbirth.) In any case, no one I know who’s ever had them is eager to repeat the experience.

Kidney stones are hard masses that can grow from crystals forming within the kidneys. Women sometimes get them, but they’re much more common in men. About three-quarters of the stones are made out of calcium oxalate.  (Uric acid stones are most commonly found in gout.)

Oxalate is an organic salt, but when combined with calcium it produces an insoluble mass called calcium-oxalate which is the most common chemical compound found in kidney stones. Urinary oxalate is the single strongest predictor of kidney stone formation- the higher the urinary oxalate, the greater the risk of oxalate kidney stones.

So anything that helps reduce urinary oxalate would help reduce the risk of kidney stones, right?

Exactly. And that’s the finding of a recent and important study in which supplementation with 900 mg EPA and 600 mg DHA, for a period of 30 days lowered the urinary oxalate by 23%, thus effectively decreasing, by a significant amount,  the risk of calcium oxalate formation.

Because 75 percent of kidney stones are formed from oxalates, you’ll want to avoid or at least reduce your consumption of foods that are high in oxalates: nuts, tea, chocolate, beets, rhubarb, and wheat bran are all on the list. Phosphate-based soft drinks are also a big problem for stone formers. A study in the Journal of Clinical Epidemiology examined 1,009 male patients and found that the guys who consumed the largest quantities of phosphate-based sodas had the highest rate of stone recurrence.

Two other things you can you do to help prevent another excruciatingly painful stone from ever forming again is to take magnesium and start  drinking a ton of water. Water will make calcium oxalate more soluble and a lot less likely to form crystals. Water and lemon juice may help as well, since a half cup of lemon juice a day will raise citrate levels, which can help fight stone formation. (Soda, on the other hand, does the opposite.) And research shows that grapefruit juice raises the risk of stones by as much as 44 percent, so if you’re prone to stone formation, avoid it. Ditto with salt.

The Magic of Magnesium

According to Alan Gaby, M.D., author of the textbook “Nutritional Medicine”, research “strongly suggests that supplementing with modest doses of magnesium and vitamin B6 can greatly reduce the recurrence rate of calcium oxalate kidney stones.” In one study, 149 patients with long-standing stones received 100 mg of a cheap form of magnesium (magnesium oxide) three times a day, equal to 180 mg per day of elemental magnesium. They also received 10 mg of  vitamin B6 once a day at the same time.

Would you like to know what happened?

The mean rate of stone formation dropped by 92.3 percent.

Another study published in the Journal of the American College of Nutrition showed that supplementing with 500 mg of magnesium a day (even without the B6) dropped stone formation by 90 percent.

“Unfortunately, many doctors remain unaware of this simple, safe, effective, and inexpensive treatment for recurrent kidney stones,” Gaby says.

5 Easy Steps for Preventing Kidney Stones

If you really want to reduce the risk of stone formation, follow these five easy steps for preventing kidney stones:

  1. Drink a ton of water. Every day
  2. Throw out your soda
  3. Take Fish Oil  daily: about 1.5 grams of combined EPA-DHA (the amount used in the study mentioned above)
  4. Take 400-800 mg of magnesium (preferably with at least 10mg of vitamin B6)
  5. Reduce or monitor your consumption of high-oxalate foods
  6. Avoid grapefruit juice
  7. Reduce salt