The development of a kidney stone, a condition called renal lithiasis, is complex. Dietary factors such as fluid intake, consumption of fruits and vegetables, use of mineral supplements and consumption of dairy products all play a role, as do heredity, high blood pressure and obesity. Calcium intake, including dairy products such as cheese, may be a factor in developing kidney stones.
Kidney Stones
A kidney stone is a solid piece of material that forms from minerals and other substances in the urine. Stones can vary in size from as small as sand or gravel to as large as a gold ball. The stone may get stuck in a ureter, one of the tubes that carry urine from the kidney to the bladder, or anywhere else in the urinary tract. Some kidney stones pass without incident; others are very painful and are accompanied by symptoms such as nausea, vomiting, fever or chills.
Kidney Stones from Calcium
There are several kinds of kidney stones, the most common of which are formed from calcium. Calcium in the urine combines with other substances such as oxalate, phosphate or uric acid. Kidney stones can also be composed of uric acid, struvite, brushite or cystine. According to an article published in the September 2006 issue of the "Nutrition Journal," dietary factors play a role in each type of stone. Hydroxyapatite kidney stones tend to form because of high calcium and phosphate in the urine. The study authors recommend that cheese be restricted with this type of stone because cheese is high in both calcium and phosphorus.
Recommendations and Research
MedLinePlus suggests that if you have calcium kidney stones, you should limit foods that have a lot of calcium. Their recommendation is for only two to three servings of foods high in calcium, such as milk, cheese, yogurt, oysters and tofu. However, the Office of Dietary Supplements says that the association between calcium stones and calcium intake is more strongly related to calcium supplements than dietary calcium source such as cheese. A study of dietary calcium intake published in "The New England Journal of Medicine" in March 1993 found that high dietary calcium intake actually decreased the risk of kidney stones.
Final Considerations
Recommendations are conflicting about the consumption of cheese for those who have have kidney stones. If you have a history of kidney stones, consult with a healthcare professional to determine the best dietary choices for your condition.
References
- "The New England Journal of Medicine"; A Prospective Study of Dietary Calcium and Other Nutrients and the Risk of Symptomatic Kidney Stones; G.C. Curhan, et al.; March 1993
- "Nutrition Journal"; Renal Lithiasis and Nutrition; F. Grases, et al.; September 2006
- MedlinePlus: Kidney Stones - Self-Care
- National Kidney and Urologic Diseases Information Clearinghouse; What I Need To Know About Kidney Stones; John Asplin, M.D., et al.; April 2007
- Office of Dietary Supplements, National Institutes of Health: Calcium
