Drinks and oxalates: 49 foods rated

Almond milk is mostly water, and it is still high here - because oxalate is water-SOLUBLE, so it moves into the liquid during soaking and blending and stays there when the solids are strained out. Straining removes the almond and keeps the oxalate.

• Noonan SC & Savage GP, Asia Pac J Clin Nutr 8 (1999)
• USDA FoodData Central

Cola contains no oxalate itself - ion chromatography measures it under 1 mg per litre. The fructose route is closed: on controlled diets of up to a fifth of calories as fructose, urinary oxalate does not move, and liver cells do not convert fructose to oxalate at all. What remains is empirical: drinking a cola raises urinary oxalate in volunteers, and in the large cohorts it is the SUGARED cola, not the diet kind, that tracks with kidney stones. The mechanism is not elucidated — calcium, acidity and magnesium shift together — but the signal is measured, and it belongs to the sugared version alone.

• Rodgers A., Urol Res 27 (1999) 77-81, urinary oxalate after a cola load
• Knight J et al., Horm Metab Res 42 (2010) 868-873, fructose is not metabolised to oxalate
• Ferraro PM et al., Clin J Am Soc Nephrol 8 (2013) 1389-1395, sugared soda and kidney stone risk
• Passman CM et al., J Endourol 23 (2009) 347-350, cola oxalate under 1 mg/L

Black tea carries oxalate in the leaf, but a cup is a dilute infusion and the leaf is discarded - most of what the plant held never reaches the water. Volume is the variable: several strong cups a day is a different exposure from one weak one, and adding milk brings calcium that binds part of what did dissolve. Noonan puts a number on that: English diets take in 70 to 150 mg of oxalate a day, and TEA is the largest single contributor of it — which is how a dilute infusion ends up at the top of a diet without being high in a cup.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8 (1999) 64–74: mean oxalate intake 70–150 mg a day in English diets, tea the largest single contributor, and soaking or cooking reduces oxalate by leaching

Cashew milk is blended from a nut that is high in oxalate, and unlike most plant milks it is usually made WITHOUT straining — the whole nut goes into the glass. Most brands are fortified with calcium, which is the one thing working the other way: it binds part of the drink's own oxalate and part of the meal's.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8:1 (1999) 64-74, oxalate content of foods and its effect on humans

Energy drinks carry little oxalate. Their relevance to stones is different and worth knowing: caffeine is mildly diuretic and sugar load matters, so the useful advice is about fluid rather than about oxalate.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8:1 (1999) 64-74, oxalate content of foods and its effect on humans

Green tea and black tea are the same leaf: Camellia sinensis, separated by oxidation, which does not remove oxalate. No published assay tells the two apart. As with black tea the variable is volume — Noonan finds tea the largest single contributor to the 70 to 150 mg an English diet takes in each day.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8 (1999) 64–74: mean oxalate intake 70–150 mg a day in English diets, tea the largest single contributor, and soaking or cooking reduces oxalate by leaching

Hazelnut milk is strained, and straining is what separates it from the cashew drink: the ground nut stays in the cloth. What passes into the bottle is the water-soluble fraction, and oxalate is water-soluble — which is why dilution lowers it without clearing it. Most brands add calcium, and that binds part of what did pass.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8:1 (1999) 64-74, oxalate content of foods and its effect on humans

Kombucha is brewed from tea, so it starts with the tea leaf's oxalate - then it is diluted, fermented and usually drunk in small bottles. Less concentrated than the tea it came from.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8:1 (1999) 64-74, oxalate content of foods and its effect on humans

Lemon juice is low in oxalate and does something better: it is a common source of citrate, and citrate is what stops calcium oxalate crystallising in urine. Stone-management guidance recommends it for that reason - this is one of the few foods on the axis that actively helps.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8:1 (1999) 64-74, oxalate content of foods and its effect on humans

Pistachio milk starts from a nut that carries less oxalate than most, so the dilution begins from a smaller number than a cashew drink does. It is also the most expensive of the plant milks, which keeps the percentage of nut in the carton low. Most brands are fortified with calcium.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8:1 (1999) 64-74, oxalate content of foods and its effect on humans

Quinoa milk is not a nut milk: it is made from a seed that is high in oxalate, and the rinsing quinoa gets before cooking — done for the bitter saponins — is not part of how the drink is made. What dilution it gets is the whole of its advantage over the grain. Most brands are fortified with calcium.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8:1 (1999) 64-74, oxalate content of foods and its effect on humans

Tea carries oxalate in the leaf, but a cup is a dilute infusion and the leaf is discarded - most of what the plant held never reaches the water. Volume is the variable: several strong cups a day is a different exposure from one weak one, and adding milk brings calcium that binds part of what did dissolve. Noonan puts a number on that: English diets take in 70 to 150 mg of oxalate a day, and TEA is the largest single contributor of it — which is how a dilute infusion ends up at the top of a diet without being high in a cup.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8 (1999) 64–74: mean oxalate intake 70–150 mg a day in English diets, tea the largest single contributor, and soaking or cooking reduces oxalate by leaching

Tonic water contains no oxalate. On this axis it counts as fluid, and fluid is the first thing stone guidance asks for - volume dilutes urine and dilute urine crystallises less.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8:1 (1999) 64-74, oxalate content of foods and its effect on humans

Walnut milk is diluted from a nut that carries less oxalate than most, and it is strained, so the ground nut is left behind. Both work in the same direction, which is why this is the mildest of the nut drinks on this axis. Most brands are fortified with calcium.

• Noonan S.C. & Savage G.P., Asia Pac J Clin Nutr 8:1 (1999) 64-74, oxalate content of foods and its effect on humans