Some are the size of a grain of sand, while others may be as large as a pearl. A few are as big as a golf ball. Some have jagged edges while others are smooth. Usually yellow or brown in colour, they form inside the kidneys or bladder, before passing out of the body via the urethra. They cause intense pain - people who've endured the agony of their passing describe the pain as unforgettable. They're called kidney stones, and in recent years the number of people suffering from them has been steadily increasing.
Also known as renal calculi, kidney stones are solid concentrations or crystal aggregations that form when the minerals and salts present in urine are out of balance. This happens when urine becomes too concentrated, usually because of lack of fluids. The minerals and salts begin to form crystals, which combine to form a stone.
The main symptom of a kidney stone is pain, which may begin in the back or below the ribs. The pain intensifies as the stone breaks loose and moves through the urether tube from the kidney to the bladder. For most people this is the first time they realise they have a kidney stone. The pain moves to the lower abdomen and groin, and blood may appear in the urine. There's also a chance a recurring urinary tract infection may develop, accompanied by feelings of nausea, vomiting, fever and a constant urge to urinate. The urine produced may be cloudy with an unpleasant odour.
Almost 80 percent of all kidney stones are the calcium oxalate type. This is not caused by excessive calcium, but because of the way it is used by the body. Limited physical activity or lack of exercise can cause the bones to release calcium, which may promote the formation of kidney stones. Excess acid in the urine may form another type of kidney stone - a uric acid stone. Struvite stones contain magnesium and ammonia, and may develop after a urinary infection. Cystine stones are the rarest type of kidney stone, and are produced by cystine building up in the urine. Cystine is an amino acid present in muscles and nerves, and the disease responsible for these stones runs in families.
Inadequate fluid intake is a major cause of kidney stones. Between two to three litres of fluid - especially water - should be ingested every day. Cranberry juice reduces the amount of calcium in the urine, and can be effective in curing kidney stones. The citrus content in fresh lemonade is another natural remedy. A reduction of sugar, meat and dairy products, refined foods, alcohol, caffeine, soda in the diet is recommended, with an increase in the amount of fibre, whole grains and vegetables. Foods rich in oxalates, such as spinach, rhubarb, strawberries, nuts, chocolate, beans and black teas should also be reduced.
The herb basil can help strengthen the kidneys. A teaspoon of basil juice mixed with a teaspoon of honey taken daily for six months will help the body expel kidney stones. Parley is another useful herb, and it's also very beneficial to the entire digestive system. The water and fibre content of celery can help prevent the formation of kidney stones.
Grapes are a good source of water and potassium salt, and their low levels of sodium chloride and albumin mean this fruit is an excellent natural treatment for kidney stones. Apples are also very effective against kidney stones. Fresh apples are the best, and in regions where natural unsweetened cider is popular there's a marked reduction in cases of kidney stones. Watermelon, either eaten fresh or drunk as a fruit juice, is another food that can be included in the diet.
People who've already experienced one or more kidney stones are at risk of developing more stones in the future. Diseases like gout, cystinuria and tubular acidosis can cause kidney stones. Chronic urinary tract infections carry the same risk. Some medications, particularly diuretics, may cause the formation of kidney stones.
It is important to find out what type of kidney stone developed, and the reasons it formed. Some of the underlying causes of kidney stones can be treated to prevent the formation of new stones. If no specific treatment exists, the risk of developing kidney stones in the future might be avoided by simply making a few changes to the lifestyle drinking more water, making a few dietary changes and increased physical activity.