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Kidney Stone Prevention Diet: 6 Tips for Preventing Renal Stones

The Kidney Stone Avoidance Diet

Looking for ways to prevent kidney stones? Try a kidney stone avoidance diet! The paragraphs below present diet-related tips that may help prevent and treat kidney stones.

Important notice: The information below and elsewhere on this website should not be taken as a substitute for professional medical or health advice. Always seek the advice of your physician or a qualified health care professional for any questions you may have regarding your medical condition.

#1: Step Up Your Fiber Intake

Dietary fiber is the part of plant foods that the enzymes in your body cannot digest. It is therefore not absorbed into the bloodstream and cannot be used for energy. Dietary fiber can be classified into two main categories: soluble fiber (dissolves in water) and insoluble fiber. Insoluble fiber has been shown to be protective against kidney stones. This is because insoluble fiber combines with calcium in the intestines, and the calcium is thus excreted with the stool instead of through the kidneys. Fiber also lowers blood cholesterol by binding to harmful cholesterol (LDL) in the small intestine and carrying it out of the body. Good sources of insoluble fiber include rice, wheat, rye, and barley.

#2: Consider Limiting Foods High in Oxalate or Oxalic Acid

If you have had an oxalate kidney stone or a calcium oxalate kidney stone, your doctor may recommend limiting foods high in oxalate or oxalic acid. Oxalic acid can combine with minerals such as calcium in the body to form crystals, which can then develop into kidney stones. Oxalate and oxalic acid are found in large quantities in plant-based foods, particularly in rhubarb and spinach. Also peanuts, tea, beets, beans, beets, berries, chocolate, dark leafy greens, oranges, tofu, and sweet potatoes contain significant amounts of oxalate/oxalic acid. In some cases, a slight intake in calcium may be recommended to accompany the decrease in oxalate. In any case, it is important to consult a doctor or a registered nutritionist before any attempts to alter the oxalate or calcium content of the diet.

A sufficient intake of water can hinder the formation of kidney stones.

#3: Drink Plenty of Water

Increasing water intake should be the cornerstone of any diet aimed at reducing the risk of kidney stones. Water keeps urine less concentrated, which can hinder the formation of kidney stones. Most experts recommend drinking at least 8 glasses of water a day. An even higher intake of water is necessary in hotter weather and for physically active people.

#4: Avoid Excess Protein

While a certain amount of protein is necessary for the proper functioning of the body, excessive amounts of animal protein should be avoided. A diet high in protein may lead to kidney stones in some people because excessive amounts of protein cause calcium to be excreted from the body, raising calcium levels in the urine. This is important news at a time when more and more people are turning into low carbohydrate, high protein diets (e.g. the Atkins diet) in the hope of fast weight loss.

#5: Follow a Low Glycemic, Low Sugar Diet

Carbohydrates that have a high Glycemic Index (GI) rating are quickly broken down by the body and cause a rapid, large rise in blood glucose levels, which in turn triggers the pancreas to release large amounts of insulin. Insulin is necessary for the body to be able to use glucose for energy, but excess insulin in the bloodstream can lead to kidney stones. Indeed, scientific evidence shows that large amounts of insulin are associated with a lower urinary citrate excretion, which in turn is associated with an increased risk of calcium stone formation. In contrast, low-GI carbs, which take much longer to digest than high-GI foods, generally cause only a small, slow rise in the blood glucose and insulin levels, and should therefore be the preferred source of carbohydrates among people who are prone to calcium kidney stones. Most non-starchy vegetables, legumes and fruit have a low GI rating while most refined carbohydrate-rich foods and sugary foods are rated high on the Glycemic Index.

#6: Limit Your Salt Intake

If you have had a calcium stone, limiting your intake of sodium (salt) may be wise. Excess sodium encourages the excretion of calcium in the body, leading to high levels of calcium in the urine. If you feel low-salt food is lacking flavor, try using spices and herbs instead of excessive amounts of salt. Be also aware of the "hidden" salt that is present in many packaged and processed foods, such as commercial cereals, canned vegetables, and frozen meals.

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