Oxalate-rich foods

Abstract

The intake of large amounts of the antinutrient oxalate can induce hyperoxaluria, an important risk factor for the development of calcium oxalate stones. The soluble and total oxalate concentrations of plants of the Fabaceae, Convolvulaceae, and Malvaceae families were determined using an HPLC-enzyme-reactor method. Sweet potato is a species of the Convolvulaceae, Fabaceae includes beans, lentils, peas, licorice and blue fenugreek, whereas okra and cocoa are species of the Malvaceae family. Total oxalate content was highest in licorice root (Glycyrrhiza glabra; 3569 mg/100 g), an important medicinal herb and sweetener in candies, blue fenugreek (Trigonella coerulea; 1246 mg/100 g) and white beans (Phaseolus vulgaris L.; 548 mg/100 g), plants of the Fabaceae family. Total oxalate content amounted to 496 mg/100 g in sweet potato (Ipomoea batatas), 619 mg/100 g in cocoa powder (Theobroma cacao) and 317 mg/100 g in okra (Abdelmoschus esculentus), the most important agricultural crops of the Convolvulaceae and Malvaceae, respectively. The findings suggested that most foods of these plant families contain high to excessively high oxalate concentrations. The consumption of these oxalate-rich plants can negatively impact calcium oxalate stone formation.

Nutrition and Kidney Stone Disease

“…However, the previous lack of accurate and complete data on the oxalate concentration of foods hindered the elucidation of the role of dietary oxalate in urinary oxalate excretion and the risk of stone formation. Analysis of the oxalate content of a wide variety of foods by a HPLC enzyme-reactor method provided a comprehensive database of the oxalate content of foods and beverages and detected a considerable number of foods with high or extremely high oxalate concentrations [55,56,59,60,[143][144][145]. An overview of foods rich in oxalate, including vegetables, legumes, fruits, cereals and pseudocereals, nuts, herbs and spices, is presented in Table 3.…”

Widening the Perspectives for Legume Consumption: The Case of Bioactive Non-nutrients

“…For example, soaking seeds of different legumes species reduced the oxalate content by 17-52% and the reduction even increased after cooking, 31-66% (Shi et al, 2018). Nevertheless, it is necessary to have into account that legumes are not the only oxalate source; cooked and raw spinach is considered the major supplier since ingestion of 50-100 g of spinach (normal portion) provides around 500-1,000 mg of oxalate (Mitchell et al, 2019); also in cocoa powder, oxalates content was found to be 619 mg/100 g; in sweet potatoes 496 mg/100 g and in okra 317 mg/100 g (Siener et al, 2020). Phytate or phytic acid, a non-proteinaceous non-nutrient (Raes et al, 2014), frequently present in soybeans, fava beans, and common beans (Table 1), can chelate Fe, Zn, and Cu, and can negatively affect their absorption in the gastrointestinal tract (Figure 1; Samtiya et al, 2020).…”

“…For example, soaking seeds of different legumes species reduced the oxalate content by 17–52% and the reduction even increased after cooking, 31–66% ( Shi et al, 2018 ). Nevertheless, it is necessary to have into account that legumes are not the only oxalate source; cooked and raw spinach is considered the major supplier since ingestion of 50–100 g of spinach (normal portion) provides around 500–1,000 mg of oxalate ( Mitchell et al, 2019 ); also in cocoa powder, oxalates content was found to be 619 mg/100 g; in sweet potatoes 496 mg/100 g and in okra 317 mg/100 g ( Siener et al, 2020 ).…”

An engineered bacterial therapeutic lowers urinary oxalate in preclinical models and in silico simulations of enteric hyperoxaluria

“…An accelerated failure time model, based on a recent epidemiological study in 279 patients with EH, predicted that a 20% decrease in UOx levels reduces the risk of a kidney stone event by 25% (D'Costa et al , 2021 ). There are currently no approved pharmacological therapies for EH, and disease management aims to decrease the risk of recurrent kidney stones by limiting dietary oxalate and fat, increasing dietary calcium intake, and maintaining adequate fluid intake (Pearle et al , 1999 ; Siener et al , 2021 ). However, the efficacy of dietary modifications alone is limited, especially in patients with severe hyperoxaluria (Schwen et al , 2013 ), and lifelong adherence to a low oxalate diet is challenging (Attalla et al , 2014 ).…”