Calcium-Oxalate Kidney Stones and Diet

Calcium-Oxalate Kidney Stones and Diet

At a recent pot luck dinner, the topic of calcium-oxalate kidney stones came up. Calcium-oxalate stones are the most common type of kidney stones.

These type of stones form when urine becomes super-saturated with calcium and oxalates. So doctors would routinely recommend low calcium diets to kidney stone formers until this study, published in the New England Journal of Medicine (NEJM), confirmed previous epidemiological studies that show animal protein to be a bigger contributor to calcium-oxalate stone formation than dietary calcium.

This led the researchers to conclude; “In men with recurrent calcium oxalate stones and hypercalciuria, restricted intake of animal protein and salt, combined with a normal calcium intake, provides greater protection than the traditional low-calcium diet.”

Prior to this and other studies, some doctors would also advise stone formers to limit intake of vegetables high in oxalates. But many began questioning this advice as the researchers who worked on the NEJM study found that urinary oxalate excretion increased in the men on the low-calcium diet, but decreased in those on the normal-calcium, low-animal protein, low salt diet.

A 2014 study showed a diet high in fruits and vegetables and other whole plant foods was associated with a reduced risk of kidney stones in postmenopausal women. The oxylates in their diet did not seem to matter.

For addition information on the impact of dietary animal protein on the formation of calcium –oxalate kidney stones and uric acid kidney stones, check out this recent video by Dr, Michael Greger.

Under certain circumstances, regular, large intake of high oxalate foods such as spinach, beet greens and swiss chard can prove to be disastrous to our kidneys. In this video, Dr. Greger explains why it’s probably a good idea that you don’t eat too much of these, especially if you have a history of kidney stones or other kidney ailments.

Stay Healthy and Strong!