About 10% of people experience an episode of kidney stones in their lifetime, and about 70% of these people experience recurrence.
About 80% of kidney stones contain calcium, and of these about 80% are calcium oxalate, either in pure form or in combination with calcium phosphate. We can therefore state that in most cases (about 65%) kidney stones are formed by important concentrations of calcium oxalate. Knowing its metabolism is therefore important to prevent the onset of nephrolithiasis and any relapses.
, a compound that occurs in needle-like crystals, known in botany as rafidi. In plants, these needles, pointed at the ends and enclosed in vacuoles, represent a defense mechanism against herbivores; plants such as Rhubarb, Altea, Dieffenbachia and Parsnip are particularly rich in it. As far as food sources are concerned, in addition to rhubarb (leaves), spinach, tea leaves, kiwi and beetroot are remembered: presence of these microscopic crystals is responsible for the intense burning sensation in the mouth and throat that some people experience after ingesting these foods. In high doses, calcium oxalate represents a real poison for the human organism, triggering severe digestive system disorders and breathing difficulties up to coma.
The "calcium oxalate present in the" organism derives both from the direct contribution of plants that are rich in it, and from the salification of dietary calcium with the oxalic acid contained in food, and from endogenous production (for example starting from vitamin C) . For this reason, in addition to removing calcium from the body, frequent ingestion of foods rich in oxalic acid can favor the onset of kidney stones in predisposed subjects.
what behavioral factors. The latter can be corrected to prevent their onset at various levels.Of all these risk factors for calcium oxalate stones, hypercalciuria is the most common, although its origins are not clearly identifiable in many patients, where the adjective "idiopathic" is forged.
dark green leaf (spinach, chard, rocket)
1) Increase the intake of fluids in order to stimulate frequent diuresis with clear urine: in this way the urine will be less concentrated, and calcium and oxalate more diluted, therefore less likely to precipitate;
2) Limit the intake of foods rich in animal proteins, especially purines (seafood, anchovies, sardines in oil, herring, caviar, offal, meat extracts, meat broth, game, dips, meats and fish fat), avoiding high-protein, ketogenic or low-carb diets. The ingestion of animal proteins increases the urinary excretion of calcium and uric acid, the latter can favor the formation of uric acid and calcium oxalate stones
3) Limit the consumption of foods rich in oxalates: see table on the side, and possibly associate them with sources rich in calcium (eg spinach + grated cheese) as a useful strategy to limit the absorption of oxalates; moreover, increase the intake of liquids for their dilution
4) Reduce the sodium intake to less than 2-3 grams per day: prefer food products without added salt; cook food with a little salt, possibly replacing it with spices; if necessary, replace traditional salt with low-sodium one; read the food labels, avoiding those that contain more than 250 mg of sodium per 100 grams of product
5) Avoid megadoses of vitamin C, which could increase the concentration of oxalates in the urine: a "possible integration will be carried out at dosages of less than 1000 mg per day
6) Dietary calcium restriction is not necessary to prevent calcium oxalate stone formation; the dietary intake of the mineral should be around one gram per day to avoid possible deficiencies, which would lead to an increased absorption of oxalates during digestion; do not abuse supplements that contain vitamin D and calcium, even if some studies show that - a despite what has been believed in the past - they can protect against kidney stones ..
7) Consume foods rich in citric acid, such as citrus fruits and lemon juice, which tend to alkalize the urine by preventing the formation of uric acid stones and calcium oxalates.
thiazides (eg hydrochlorothiazide, chlorthalidone and indapamide): they have been shown to be useful in reducing calcium and the onset of nephrolithiasis. Furthermore, these drugs induce a positive balance of calcium, consequently promoting the increase in bone mineral density. Dietary sodium restriction is indicated during therapy, while the potassium intake should be increased to avoid hypokalemia, which at in turn can lead to hypocitraturia. The usual starting dose is 12.5-25 mg of chlorthalidone or hydrochlorothiazide. Most patients should receive potassium citrate supplementation. Potassium-sparing diuretics such as amiloride may help avoid hypokalaemia, but triamterene should be avoided due to its low solubility.
