I ran across this lovely jewel today….apparently they have proved that people who are obese and undergo WLS, the are more likely to get kidney stones than their non WLS counterparts. Even people with no previous stones or a family history of stones show a marked concentration of the ingredients for the stones. The researchers found that the excretion of a material called oxalate in urine was significantly greater in the participants who had the surgical procedure than those who did not (47 percent, compared with 10.5 percent, respectively). In addition, the amount of a chemical called citrate in the urine was low in many gastric bypass patients in comparison to the obese nonsurgical group (32 percent to 5 percent). Oxalate is found in the majority of kidney stones, while citrate inhibits stone formation.
“Almost half of the patients who had undergone gastric bypass and did not have a history of kidney stones showed high urine oxalate and low urine citrate — factors that lead to kidney-stone formation,” said Dr. Naim Maalouf, assistant professor of internal medicine in the Charles and Jane Pak Center for Mineral Metabolism and Clinical Research and the study’s lead author.