Passing a kidney stone can give you one of the worsgoing: nobody who gets it ever wants it to happen again. The key to avoiding this it is not to make stones in the first place, and we know quite a lot about how to prevent that.
Most stones are formed from having too much calcium in your blood from non-food sources such as hard water, and not enough magnesium. Either of these will react together with oxalic acid, wasted from your metabolism or eaten in certain foods. Calcium oxalate easily forms crystals whereas magnesium oxalate is more soluble: if the balance is too heavily in favour of calcium you are very likely to form stones. So preventing them comes down to keeping that balance right, at the same time watching how much oxalic acid you are likely to be forming.
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