10 tips for healthy kidneys and how to avoid stones

1. Drink water

Drinking water helps dilute the urine, reducing the risk of stones crystallising in it. Drink enough to ensure that urine remains pale yellow.

2. Drink coffee and tea

Drinking coffee and tea has also been associated with reduced kidney stone risk. It seems it's not only water, but other fluids too, that confer some protection for those with a history of kidney stones.

3. Reduce oxalate in the diet

The vast majority of kidney stones are made of calcium oxalate. Reducing oxalate intake from the diet reduces the level of this substance in the urine, thereby reducing risk of stone formation. Oxalate-rich foods to avoid include spinach, rhubarb, chocolate, nuts and strawberries.

4. Increase calcium in the diet

Individuals with a history of kidney stones are often advised to cut down on calcium. However, calcium can bind to oxalate in the gut, and this appears to reduce the risk of stone formation. Calcium-rich foods include plain yoghurt, tinned fish, sesame seeds, figs and beans.

5. Keep the diet plant-based

Animal protein can increase calcium levels in the urine, which appears to be associated with an increase in kidney stone risk. For the best protection from kidney stones, the diet should be rich in plant-based foods such as fruits, vegetables, beans, lentils, nuts and seeds.

6. Eat plenty of fruit and veg

Fruit and vegetables are believed to be particularly beneficial: these are rich in potassium which has been linked with reduced kidney stone risk.

7. Cut back on salt

Salt increases calcium excretion in the urine, which can increase the risk of stone formation. In general, most of the salt we consume is not added during cooking or at the table, but comes from processed foods such as bread, cheese, savoury snacks, breakfast cereals and ready-meals.

8. Supplement with magnesium

Magnesium helps transform oxalate into other substances in the body, and is believed to help reduce the risk of stone formation. Take 300mg per day.

9. Supplement with vitamin B6

Vitamin B6 also participates in the metabolism of oxalate, and may also help to keep kidney stones at bay. This should be taken at a dose of 25-50mg per day, preferably as part of a general B-complex supplement.

10. Take quebra pedra

This South American herb is traditionally used to dissolve kidney stones. In practice, I have found it helpful for individuals who have stones lodged around their kidneys or in the bladder. Quebra pedra is available in tea and pill form from Rio Trading on 01273 570987.

· Dr John Briffa's latest book is Natural Health for Kids from A-Z, published by Penguin, £16.99