Are you tired of suffering from painful, recurring kidney stones? Do you have a close relative who has experienced this nightmare? Kidney stones tend to run in families. Learning how to prevent kidney stones from forming can save you a lot of pain and misery in the future, even if you have not yet had this experience.

Kidney stones are hard masses that are formed from crystals of salts and minerals within the kidneys.

Many people do not realize that kidney stones can be present for years and never produce symptoms. Once the stones grow large enough to block urine flow, the pain can be excruciating.

The most common type of stone is made from calcium oxalate. Because oxalate is a major promoter of calcium stones, it is important to reduce intake of foods that are high in oxalates.

Foods that significantly increase urinary oxalate levels include beer, chocolate, peanuts, strawberries, rhubarb and beet greens.

Citrate supplementation makes the urine more alkaline and has been shown to decrease the potential to form stones.

Studies have shown that subjects taking 400 milligrams per day of magnesium citrate experienced a significant reduction in oxalate stone formation,

Lemon juice is high in citrate. Taking lemon juice mixed with water has been shown to increase urinary citrate levels.

Drinking 64 ounces of water per day decreases the concentration of stone particles in the urine and increases the urinary flow rate.

Taking vitamin B6 has been shown to reduce elevated urinary oxalate levels. Studies have shown that supplementing with 50 milligrams per day significantly lowers the risk of kidney stone formation.

Uric acid stones are formed from the accumulation of uric acid crystals, a byproduct of protein metabolism.

Intake of red meat (beef, pork and lamb), seafood (tuna, shrimp, lobster and scallops), mushrooms, organ meats, legumes, fructose, sugary and fatty foods should be reduced, as these foods increase production of uric acid. Because alcohol interferes with the elimination of uric acid from the body, intake of beer and wine should be minimal.

Studies have shown that taking one gram of vitamin C per day increases urinary oxalate levels and reduces uric acid levels..

People who consumed more calcium in the diet have been shown to have a decreased risk of forming stones. Lower uric acid levels were seen in subjects who consumed yogurt or low fat milk at least once every other day.

Magnesium citrate and potassium citrate have been shown to decrease the acidity of urine and should be taken to reduce the possibility of forming uric acid stones.

Several studies have shown that consuming a diet consisting of fresh fruits, vegetables, low fat dairy products and whole grains while limiting intake of salt, sweetened beverages, red and processed meats led to a 45% decreased risk of forming kidney stones. This Mediterranean type diet provides significant amounts of potassium, magnesium and oxalate.

Products mentioned include:

1. Vitamin B6 = Solar Vitamin B6

2. Vitamin C = Integrative Therapeutics Vitamin C

3. Magnesium/Potassium Citrate = Thorne Research Potassium-Magnesium Citrate

Researchers have found another reason to eat well: a healthy diet helps prevent kidney stones. Loading up on fruits, vegetables, nuts, low-fat dairy products, and whole grains, while limiting salt, red and processed meats, and sweetened beverages is an effective way to ward off kidney stones, according to a study that appeared in the August 13th, 2009 issue of the Journal of the American Society Nephrology (JASN). Because kidney stones are linked to higher rates of hypertension, diabetes, increased body weight, and other risk factors for heart disease, the findings have considerable health implications.
Eric Taylor, MD (Maine Medical Center) and his colleagues at Brigham and Women’s Hospital conducted a large study to determine the effects of healthy eating habits on the formation of kidney stones. The investigators collected information from individuals enrolled in three clinical studies: the Health Professionals Follow-up Study (45,821 men followed for 18 years), the Nurses’ Health Study I (94,108 older women followed for 18 years), and the Nurses’ Health Study II (101,837 younger women followed for 14 years).
Dr. Taylor’s team assigned a score to each participant based on eight components of a DASH (Dietary Approaches to Stop Hypertension) style diet: high intake of fruits, vegetables, nuts and legumes, low-fat dairy products, and whole grains and low intake of salt, sweetened beverages, and red and processed meats. Individuals with higher DASH scores consumed diets that were higher in calcium, potassium, magnesium, oxalate, and vitamin C and lower in sodium.
A total of 5,645 incident kidney stones developed in the participants in the three studies. In each study, participants with the highest DASH scores were between 40% and 45% less likely to develop kidney stones than participants with the lowest DASH scores. The reductions in kidney stone risk were independent of age, body size, fluid intake, and other factors.
Because a DASH-style diet may affect the development of hypertension, diabetes, and other chronic diseases associated with kidney stones, the researchers also performed an analysis limited to study participants without hypertension or diabetes. Even among those individuals the DASH diet reduced the risk of kidney stones.
Many of the medications used to treat kidney stones have unpleasant side effects. This study indicates that adopting a DASH-style diet may be an effective alternative.

Relationship of animal protein-rich diet to kidney stone formation and calcium metabolism.

Breslau NA et al.

Source

Center in Mineral Metabolism and Clinical Research, Department of Internal Medicine, Dallas, Texas.

Abstract

We wished to determine whether different types of dietary protein might have different effects on calcium metabolism and on the propensity for renal stone formation. Fifteen young normal subjects were studied during three 12-day dietary periods during which their diet contained vegetable protein, vegetable and egg protein, or animal protein. While these three diets were constant with respect to Na, K, Ca, P, Mg, and quantity of protein, they had progressively higher sulfur contents. As the fixed acid content of the diets increased, urinary calcium excretion increased from 103 +/- 15 ( +/- SEM) mg/day (2.6 +/- 0.4 mmol/day) on the vegetarian diet to 150 +/- 13 mg/day (3.7 +/- 0.3 mmol/day) on the animal protein diet (P less than 0.02). Despite the increased urinary calcium excretion, there was a modest reduction of urinary cAMP excretion and serum PTH and 1,25-dihydroxyvitamin D levels consistent with acid-induced bone dissolution. There was no change in fractional intestinal 47Ca absorption. The inability to compensate for the animal protein-induced calciuric response may be a risk factor for the development of osteoporosis. The animal protein-rich diet was associated with the highest excretion of undissociated uric acid due to the reduction in urinary pH. Moreover, citrate excretion was reduced because of the acid load. However, oxalate excretion was lower than during the vegetarian diet [26 +/- 1 mg/day (290 +/- 10 mumol/day) vs. 39 +/- 2 mg/day (430 +/- 20 mumol/day); P less than 0.02]. Urinary crystallization studies revealed that the animal protein diet, when its electrolyte composition and quantity of protein were kept the same as for the vegetarian diet, conferred an increased risk for uric acid stones, but, because of opposing factors, not for calcium oxalate or calcium phosphate stones.

PMID: 2826524 [PubMed - indexed for MEDLINE]

J Urol. 2007 Jun;177(6):2179-84.

Reduction of renal stone risk by potassium-magnesium citrate during 5 weeks of bed rest.

Zerwekh JE et al.

Source

Center for Mineral Metabolism and Clinical Research, and the Department of Physical Medicine and Rehabilitation, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.

Abstract

PURPOSE:

Exposure to the microgravity environment of space increases the risk of kidney stone formation, particularly for calcium oxalate and uric acid stones. This study was performed to evaluate the efficacy of potassium alkali as potassium-magnesium citrate in reducing renal stone risk and bone turnover.

MATERIALS AND METHODS:

This study was performed as a double-blind, placebo controlled trial. We studied 20 normocalciuric subjects randomized to either placebo or potassium-magnesium citrate (42 mEq potassium, 21 mEq magnesium, 63 mEq citrate per day) before and during 5 weeks of strict bed rest. The study was performed in the General Clinical Research Center and under a controlled dietary regimen composed of 100 mEq of sodium, 800 mg of calcium, 0.8 gm/kg animal protein and 2,200 kcal per day. Two 24-hour urine collections were obtained under oil each week for assessment of stone risk parameters and relative saturation of calcium oxalate, brushite and undissociated uric acid. Blood was also collected for determination of serum immunoreactive parathyroid hormone and vitamin D metabolites.

RESULTS:

Bed rest promoted a rapid increase in urinary calcium excretion of approximately 50 mg per day in both groups. Despite this increase subjects treated with potassium-magnesium citrate demonstrated significant decreases in the relative saturation of calcium oxalate and in the concentration of undissociated uric acid compared to placebo. Immunoreactive parathyroid hormone, serum 1,25-dihydroxyvitamin D and intestinal calcium absorption all decreased in both groups with no difference in response between the 2 treatment arms.

CONCLUSIONS:

Provision of alkali as potassium-magnesium citrate is an effective countermeasure for the increased risk of renal stone disease associated with immobilization. Despite an increase in urine calcium concentration, the relative saturation of calcium oxalate decreased due to citrate chelation of calcium and the concentration of undissociated uric acid decreased due to the significant increase in urine pH.

PMID: 17509313 [PubMed - indexed for MEDLINE]