Effect of n-3 Fatty Acid Supplementation on Urinary Risk Factors for Calcium Oxalate Stone Formation

Abstract

Results show that 30-day n-3 fatty acid supplementation effectively decreases urinary oxalate excretion and the risk of calcium oxalate crystallization. The mechanism of the physiological effect may be decreased cellular oxalic acid exchange attributable to an altered fatty acid pattern of membrane phospholipids with concomitant changes in oxalate transporter activity. Calcium oxalate stone formers may benefit from long-term n-3 fatty acid supplementation.

Fish Oil Supplementation and Urinary Oxalate Excretion in Normal Subjects on a Low-oxalate Diet

“…Again, dietary components were not strictly controlled in this study. Siener et al 9 studied 15 healthy subjects who consumed a standardized diet for 5 days, a self-selected diet for 20 days, and a standardized diet again for 5 days. Each participant took 900-mg EPA and 600-mg DHA daily for the last 25 days of the study.…”

“…It could be that the mechanisms proposed by Siener et al, alterations in renal secretion of oxalate or a reduction in net gastrointestinal oxalate absorption, are valid. 9 Perhaps, the responses would be different in a diseased cohort. Our subjects may have had low levels of oxidative stress.…”

“…Our cohort size was relatively small, but the number is comparable to that of Siener et al 9 In addition, we measured neither the plasma levels of fatty acids in red blood cell membranes to assess compliance with the fish oil supplement regimen nor the markers of oxidative stress.…”

“…6 It has been demonstrated that the administration of fish oil, a rich source of omega-3 fatty acids, reduces urinary oxalate excretion. 7–9 Siener et al 9 attribute this to an altered fatty acid pattern of membrane phospholipids and changes in oxalate transporter activity. This can result in altered gastrointestinal and/or renal oxalate handling and promote reduced urinary oxalate excretion.…”

Micronutrient Metabolism in Hemodialysis Patients

“…These could also significantly reduce inflammation, fibrosis and oxidative stress following renal injury (Soumura et al, 2010;Peake et al, 2011). Moreover, fish oil supplements (900 mg of EPA and 600 mg of DHA/day for 1 month) may decrease urinary oxalate excretion and the risk of calcium oxalate crystallization attributable to an altered oxalate transporter activity (Siener et al, 2011). Chronic hemodialysis patients reportedly have significantly low concentrations of EPA and DHA in the plasma and cell membranes (Saifullah et al, 2007;Nakamura et al, 2008;Madsen et al, 2011).…”