Kidney Stones and Diet

What role do our kidneys play?

Your kidneys are a vital organ that act to filter your blood from toxins and other impurities and produce urine. They also function to balance pH, hormone and salt levels, as well as regulating blood pressure. Therefore, it is crucial that you maintain good kidney health to prevent the development of chronic diseases that could lead to kidney failure. By maintaining a healthy lifestyle and diet, you also act to prevent the formation of kidney stones, which are painful, potentially dangerous obstructions that can occur in your urinary system.

This article aims to provide a guide for how you can keep your kidneys healthy through lifestyle and diet, as well as what to avoid to ensure that you limit formation of kidney stones and related complications.

What are kidney stones?

Signs and symptoms:

Kidney stones are one of the most common disorders of the urinary system and are made of calcified minerals and salts, mostly calcium oxalate and uric acid (which is a byproduct of protein metabolism). Kidney stones may be asymptomatic if they are present in the kidneys and are not obstructing the flow of urine, however, when they move into the ureters, there is risk of severe pain, infection and even kidney damage. Kidney stones smaller than 4mm may be able to pass by themselves, with the aid of pain medication and lots of water, but larger calcifications may need medical intervention.

Cause:

Kidney stones most commonly form when waste waiting to be expelled as urine is not diluted, thus containing concentrated levels of substances such as oxalate, calcium and uric acid, which solidify into crystals and get stuck. Like any condition, genetics may play a role in your chances of developing kidney stones, as well as any pre-existing medical conditions, current medications, digestive issues or surgeries, and lifestyle and dietary habits, such as being sedentary or eating certain foods that are listed below.

Treatment:

While kidney stones are common, they are also easily treated. This depends on the size of the stone, as well as where in the urinary tract it is lodged. There have been recent developments for the treatment of kidney stones, where a fiberoptic scope is passed up the ureter to the kidney where the stone can be visualised. A laser fibre is then sent to fragment the stone and make it easier for the kidney to flush it out. While patients previously needed to undergo surgery and spend several days recovering in hospital, they are now able to undergo this simple pulverisation procedure in one day.

How can you prevent kidney stones?

While there are now treatment options available for kidney stones, your lifestyle choices can play an important role in preventing their development in the first place, which could save you a lot of pain down the track. The following lifestyle habits all ensure healthy cardiovascular health and thus healthy kidneys.

Exercise and lifestyle:

  • Regular exercise
  • Monitoring blood sugar levels
  • Not smoking
  • Stay hydrated
    • By drinking plenty of water, you are ensuring that your urine remains diluted and prevents salts from crystalising into kidney stones.
    • If you have previously suffered from kidney stones, you can reduce your chance of recurrence from 50% to 15% over 5 years by drinking 2L of water per day.

Diet:

Your diet can play a major role in whether you develop kidney stones or not, so let’s take a look at some foods to include in your diet, and some to avoid.

Foods to ensure healthy kidneys:

  • Citric acid (from oranges, lemons and grapefruits) prevents calcium from binding to other substances, therefore reducing the formation of crystals.
  • Consume high calcium foods, such as dairy products, with foods containing oxalates (chocolate, sweet potato, peanuts, seeds, beets, okra, spinach, tea, soy products)
    • This ensures that the calcium and oxalates bind in the intestinal tract instead of in the kidneys.

Foods to avoid

  • Limit foods containing oxalates (chocolate, sweet potato, peanuts and seeds, beets, okra, spinach, tea, soy products).
  • Avoid foods high in salt:
    • Sodium helps move calcium from the blood to the urine, so excess salt results in more calcium being present in your kidneys.
  • A diet high in red meats, organ meats and shellfish:
    • These foods contain a naturally occurring chemical called purine, which leads to a higher production of uric acid, and uric acid stones.
  • Limit sugar intake in order to not develop or exacerbate kidney stones
  • Alcohol reduces the removal of uric acid from your body, so keep it to a minimum

If you suspect you may be suffering from kidney stones, or are concerned about your overall kidney health, contact Katelaris Urology to book a consultation with a kidney stone specialist to discuss treatments, management and prevention. Our experienced urologists can advise you on the correct nutritional steps that you can take to prevent kidney stones from recurring in the future.

References:

  1. Harvard Health Publishing: https://www.health.harvard.edu/blog/5-steps-for-preventing-kidney-stones-201310046721
  2. National Library of Medicine: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4189688/
  3. Healthline: https://www.healthline.com/nutrition/foods-to-avoid-with-kidney-disease
  4. National Kidney Foundation: https://www.kidney.org/atoz/content/diet#:~:text=To%20prevent%20uric%20acid%20stones,and%20low%2Dfat%20dairy%20products.
  5. National Institute of Diabetes and Digestive and Kidney Disease: https://www.niddk.nih.gov/health-information/urologic-diseases/kidney-stones/eating-diet-nutrition
  6. Associates in Nephrology: https://www.associatesinnephrologypc.com/2020/01/19/can-citric-acid-prevent-kidney-stones/
  7. Medical and Dietary Therapy for Kidney Stone Prevention: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4265710/#:~:text=Citric%20acid,-Consuming%20fruit%20juice&text=Citrate%20prevents%20stone%20formation%20by,prevents%20crystal%20growth%20%5B6%5D.