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Comment by hackerlight | Hacker News Reader

Hmm? Oxalates causing less severe damage (kidney stones) is more common than just one woman. If you are a vegan you know you need to go easy on things like raw spinach and almonds.

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Wait how easy do I need to go on the almonds? I’ve been eating maybe half a pound a week.

Despite your statement I don’t think this knowledge is automatically distributed amongst vegans.

A̶r̶s̶e̶n̶i̶c̶ Cyanide is the thing to watch for I believe. Stay away from bitter almonds, roasted should be fine. You'd have to eat a 25 Kg bag of sweet almonds to get into trouble. Not sure about the cumulative effects though, that might be worth checking into.

I assume this issue is the same with almond milk? I'm almost always buying oatmilk, though.

That stuff is not what you think, look up a video on it to be enlightened.

Almond milk or oat milk?

Not Arsenic, but rather bitter almonds contain compounds that the body degrades into cyanide.

Ah yes, that was it, sorry for mixing those up. But regardless, bad idea to eat any sizeable quantity of bitter almonds.

Cyanogenic glycosides. Amygdalin in bitter almond.

Almonds are one of the highest-oxalate foods but I think generally it's fine unless you're prone to calcium oxalate kidney stones. But most people find out they're prone when they get their first stone.

I've gotten two and don't recommend. Things that help, short of the sort of restrictions I'm stuck with: drink lots of water with high-oxalate foods, and eat foods high in calcium with them. The calcium binds with the oxalate in your guts instead of your kidneys and passes right out. Some people dissolve a calcium pill in the water they boil spinach in.

They can see tiny stones in your kidneys with a scan so it's possible to check before you get a real problem, though I don't know if they would without any symptoms.

> Despite significantly more dietary oxalates (254 mg/day) and oxalate-containing foods such as nuts, vegetables, and whole grains, participants with higher DASH scores have a 40–50% decreased risk of kidney stones [68]. This is perhaps attributed to the protective and synergistic effects of phytate, potassium, calcium, and other phytochemicals all abundant in the DASH dietary pattern. Similar findings regarding the protective role of vegetables on urolithiasis risk were reported by Zhuo et al. [69]. While animal protein consumption was associated with higher kidney stone risk, vegetable and tea consumption were associated with a decreased risk of stone formation.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7600777/

A lot of the "common sense" about oxalates just sound like social media memes.

It's possible to eat a DASH diet while leaving out the foods with the highest oxalates. It's what I do myself.

Avoiding high-oxalate foods if you're prone to oxalate stones isn't a meme, it was the advice of my urologist and the printed pamphlets he gave me. Along with drinking plenty of water, especially with meals as I mentioned above. As for calcium, it's mentioned as protective in your quote.

Could you bring some empirics to the table for normal people having a common problem with oxalates at normal doses without predisposing issues like kidney disease or the ones the woman had in the case study?

Does "going easy on oxalates" just mean you have fewer than six spinach smoothies per day?

I'm used to these dietary memes cashing out into either trivial claims or nothing burgers.

> Oxalic acid has an oral LDLo (lowest published lethal dose) of 600 mg/kg.[62] It has been reported that the lethal oral dose is 15 to 30 grams.

and

> Frozen commercially available spinach in New Zealand contains 736.6 ± 20.4 mg/100g wet matter (WM) soluble oxalate

while the USDA says about 900 mg per 100 g for American spinach on average.

So roughly 1% of the wet spinach by weight. 1 kilo of high-oxalate spinach probably has 10 - 20 grams of oxalic acid. That's a lot of spinach, but probably chuggable in one day in smoothie format. Far too close to the LD50 estimate for my comfort!

For one large salad, it's unlikely to exceed a couple grams. I'm unsure about the effects of chronic lower dose exposure.

This is what I mean, though. How many people regurgitating "Be sure to watch out for oxalates!" know that we're talking about thousands of grams of spinach?

Looking it up, people generally eat 50-200mg of oxalates per day with 1000mg being the outlier high end.

Eat your spinach. If you're worried, then cook it.

Well there's the dose that kills you, but there's also the dose that over time gives you kidney stones, if you're prone to that.

Do you not have to worry about oxalates from raw spinach and almonds if you're not vegan? What protects you from kidney stones in animal foods?

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