Do you recommend malic acid supplementation for patients with recurrent calcium oxalate nephrolithiasis and hypocitraturia?

F. Malic acid, like citric acid, is metabolized as a protonated acid and used as a metabolite—it produces no alkali. Malate is metabolized as an acid and in doing so takes up a proton—just as citrate does—producing new bicarbonate, and so is an alkali.

Rodgers et al., PMID 24059642 reports malic acid increasing urine pH as if it were an alkali. Rodgers is a good scientist, but I cannot understand how this occurred, and there are no reports of replication. No OTC malate salts are currently marketed.