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Taking the Ouch Out of Oxalate

Oxalates image
ARS geneticist Beiquan Mou and colleagues analyzed hundreds of spinach plants to find ones with less oxalate, a compound linked to kidney stones.

If one of your parents or grandparents ever suffered from a painful kidney stone, you might want to tell them there's a bit of good news.

Oxalic acid, or "oxalate," is a naturally occurring plant chemical which, in the human diet, can react with calcium, iron, and other minerals to inhibit mineral absorption. Foods such as tea, beets, rhubarb, strawberries, spinach, and chocolate are known to increase oxalate in the urine and may contribute to kidney stone formation.

Spinach in particular contains higher concentrations of oxalate than most crops, but it is also considered healthful because it is rich in a number of key nutrients.

Scientists with the ARS's Crop Improvement and Protection Research Unit in Salinas, CA, and the University of Arkansas conducted a study analyzing the genetic code of 310 spinach varieties and identified 8 spinach varieties that have low oxalate levels, which is sometimes linked to better health.

If you'd like to learn more read, "Making Spinach with Low Oxalate Levels".