Acute Effect of High Fat Intake on Urinary Acidification Parameters in Uric Acid Stone Formers and Non-Stone Forming Controls

Uric acid kidney stones have increased in prevalence alongside higher rates of diabetes and metabolic syndrome. These stones form because of overly acidic urine which can result from lack of ammonia in the urine, which then causes uric acid to precipitate. We found that providing fat meals acutely lowered urinary ammonium levels in uric acid stone formers (UASFs) and in control subjects. We interpret that free fatty acids may limit the amino acid breakdown needed for ammonia production.