Diet in kidney stones guidelines:
Kidney stones is a disease consisting of precipitation in the urinary tract of insoluble deposits of chemicals, which are normal or abnormal component of urine. Kidney stones is one of the most common diseases of the urinary tract. Much more likely it is to men: get sick three times more often than women. There are several factors influencing the development of the disease: genetic predisposition, abnormalities of the urinary tract, infections, medications and poor diet. The precipitation of stones occurs when the concentration of the compounds in their composition exceeds the threshold of solubility in the body. Enlarging of the stones may have serious consequences, such as total urinary tract obstruction or destruction of renal parenchyma. Stones may occur with both acute symptoms - renal colic, urinary bladder and hematuria - as well as without symptoms. This second case occurs when the stone is rounded and does not clog the urinary tract.
There are several types of kidney stones - depending on what substance is the main component of stones. The most common are:
1. oxalate stones;
2. urate stones;
3. phosphate stones;
4. cystine stones.
Kidney stones are treated pharmacologically, but an important role in the therapy also plays a diet, with modifications depending on the type of kidney stones. Diet is determined and controled by the dietitian in close cooperation with physician. The rule, which applies to all varieties of this disease, is the need to increase the amount of fluid in the daily food intake up to 4-5 liters a day. The aim is to increase urine output in a given unit of time, the diuresis, thereby diluting the urine components undergoing crystallization. This is particularly important in the postprandial periods , and during the night. For all patients with stones it is also important to limit consumption to 60 grams of protein a day, because it acidify body fluids , and urine. Other dietary recommendations vary depending on the type of stones.
Oxalate found in urine are derived not only from the gastrointestinal tract, but also from metabolic transformations of ascorbic acid and glycine. The main principle is, however, limiting dietary oxalate in the diet, because it is the simplest way to achieve lower levels of this component in the urine. The diet should exclude all products that are a rich source of oxalate, above all: sorrel, spinach, rhubarb, beets, chocolate, coffee and tea. In patients suffering from intestinal form of the stones (it comes to increased oxalate absorption from the gastrointestinal tract) participation of foods rich in calcium should be increased. There is a close relationship between the degree of absorption of oxalate from the gastrointestinal tract and the calcium-phosphate. Increasing the amount of calcium in the diet will reduce the absorption of oxalate.
The basis for dietary management of such stones is alkalinization of the urine (reduction of hydrogen ion concentration) to pH 6:6-7, because the increase of urinary pH increases the solubility of urate. Such a favorable pH is achieved by proper selection of products, mainly eating dairy foods , and large amounts of fruits and vegetables. If diet itself does not allow the maintenance of proper pH of urine, it is necessary to give the sick person a sodium bicarbonate in an amount determined by physician. The second principle of this diet is to limit the quantities of products that are the source of purines. The amount of purine compounds in the diet is particularly important, because they are metabolized to uric acid and therefore contribute to an increase in its concentration in blood and urine. The source of these compounds are primarily meat products - offal (liver, kidney, brain and heart), boiled and meat sauces, meat jelly, sardines and herring. The plant products rich in purines should be mentioned first of all legumes (peas, beans, lentils and beans), and stimulants: cocoa, coffee and tea. Purine-rich compounds are also fungi. You also need to avoid fried, baked and stewed foods. Definitely the best method is cooking in water or steaming. The meat should be cooked in plenty of water, and created in this way broths should not be used for cooking soups and sauces. The most recommended meats are lean: chicken, turkey and veal. However, their amount in daily food intake should not exceed 100-150 g.
Phosphate stones are formed of calcium phosphate or magnesium ammonium phosphate (struvite stones) in low-acidification of urine. In case of stones formed from calcium phosphate due to excessive absorption of calcium from the gastrointestinal restriction of products containing calcium is recommended. In other cases, such dietary restrictions are unfavorable, they may in fact be the cause of the negative balance of calcium in the body. In the treatment of struvite stones acidification of urine is essential. But this can not be achieved solely through the diet, in this case it is necessary to include acidifying medicines.
This type of stones is formed as a result of impaired absorption of the return of one of the amino acids - cystine. The treatment is a diet limiting the amount of cystine , and methionine - a compound that is also an amino acid that the body in large part is converting to cystine. Vegetable products, milk and dairy products contain the least of these amino acids. They just should be the basis of the diet, so you should limit your consumption of meat and meat products.