Oxalic acid is poisonous? Should I stop eating spinach then? Oh, looks like the article mentions this actually:
> Chard and spinach, in fact, contain even more oxalic acid than rhubarb—respectively, 700 and 600 mg/100 g, as opposed to rhubarb’s restrained 500. Rhubarb’s killer reputation apparently dates to World War I, when rhubarb leaves were recommended on the home front as an alternative food. At least one death was reported in the literature, an event that rhubarb has yet to live down.
> Oxalic acid does its dirty work by binding to calcium ions and yanking them out of circulation. In the worst-case scenario, it removes enough essential calcium from the blood to be lethal; in lesser amounts, it forms insoluble calcium oxalate, which can end up in the kidneys as kidney stones. In general, however, rhubarb leaves don’t pose much of a threat. Since a lethal dose of oxalic acid is somewhere between 15 and 30 grams, you’d have to eat several pounds of rhubarb leaves at a sitting to reach a toxic oxalic acid level, which is a lot more rhubarb leaves than most people care to consume.
That actually sounds like I should be careful with how I consume my spinach (or chard or rhubarb), but more for the sake of kidney stones. I wonder if adding milk or other calcium-rich foods helps?
[one search for calcium-rich foods later]
So spinach is apparently rich in calcium? I'm getting really confused now.