The incidence of urolithiasis (kidney and ureteric stones) is on the rise in few states of India. This problem usually affects the young population.
The chances of its recurrence is 7% per year meaning that the chances of reforming the stone is 35% at the end of 5yrs and more than 50% at the end of 10yrs.
The treatment of urolithiasis is not only surgical or endoscopic removal of the stone but also prevention of further stone formation. By making changes in the lifestyle and dietary modification one can reduce the chances of recurrence.
The most common type of kidney stones result from too much calcium and oxalate in the urine. These minerals bind together as crystals, forming stones.
The following dietary guidelines can help to prevent kidney stones.
Drink plenty of fluid
- Drink more fluid, especially water
- Drinking water helps to flush out the kidneys and dilute stone-forming substances, making stones less likely to form.
- Drink at least 3 litres, or 12 cups, of fluid daily. At least half of this should be water (soda, mineral, spring or plain tap water).
- Have a cup of fluid (250ml) each hour during waking hours, and a large glass of water before going to bed. Drink a glass of water if you wake up during the night.
- Spread out your fluid intake during the day.
- Avoid strong black tea and orange juice, as these are high in oxalates.
- Avoid grape fruit juice, cranberry juice (if more than 500ml/day) and sugary drinks. Drinking large amounts of sugary drinks (softdrink, cordial) can lead to weight gain. Choose diet or low joule drinks to limit weight gain.
- Lemon juice is a good source of citrate which helps to prevent stones forming.
- Drink 100ml of lemon juice daily (could be added to water).
Limit salt intake
Salt (sodium) increases the amount of calcium in your urine. Limit sodium intake to less than 2300mg per day.
To reduce salt /sodium:
- Buy fresh food, or foods without salt - fruit, fresh vegetables, fresh meats, chicken, fish, eggs, porridge, rice, pasta
- Most sodium (75%) comes from processed foods. Limit processed foods high in salt e.g. soup, sauces, gravy, crisps and snack foods.
- “low salt” or “no added salt” foods are the best choices. Look for a sodium content less than 150 mg per serve as a guideline. Note that some “reduced salt” products can still contain high levels of sodium.
- Do not add salt at the table or in cooking.
What can I use instead?
- freshly ground pepper, dry mustard powder
- lemon juice, lime juice, vinegar
- a sprinkle of dried herbs or chopped fresh herbs
- garlic, curry, chilli, onion, fresh ginger, spring onions
Limit foods high in oxalate
- Reducing oxalate in your diet helps to reduce the amount of oxalate in your urine.
- Limit intake of : rhubarb, spinach, silverbeet, beetroot, eggplant, sweet potato, celery, leeks
- nuts, peanut paste
- strong black tea, orange juice chocolate
- wheat bran and wheat germ
- berries (eg strawberries, blackberries), dried figs
Include adequate calcium in your diet
- Dietary calcium is important for your bones and teeth. Adequate dietary calcium intake is recommended.
- Include at least 2-3 choices daily from the following list
- 250ml milk (eg trim, skim, full cream, calcium-fortified soy milk)
- 200ml high calcium milk eg Physical 200g (small tub) yoghurt
- 40g cheese (2 slices) 3 scoops ice cream
Include only a moderate amount of animal protein
- Limit protein from meat, seafood, fish, chicken, eggs to a moderate serve (120 -150g) daily (cooked) (note 60g meat = 2 eggs)
- Do not take Vitamin C supplements (also known as ascorbic acid, calcium ascorbate)
- Do not take Vitamin D supplements or cod liver oil
Choose wholemeal and wholegrain foods
- Eating foods higher in fibre can decrease the risk of stone formation by reducing the amount of calcium and oxalate you absorb
- Choose wholemeal and wholegrain breads, flour, cereals, pasta, biscuits and crackers
Increase fruit and vegetable intake
Avoid dry fruits in excessive quantity. Almonds inhibits stone formation.