Associations Between Diet and Kidney Function Decline Discovered

Boston, MA, April 16, 2010 --(PR.com)-- Researchers at Brigham and Women’s Hospital (BWH) found that in women with well-preserved kidney function, a diet high in animal fat was associated with presence of microalbuminuria, an early sign of kidney and vascular disease, whereas diets with low sodium and high beta-carotene may reduce the risk of kidney function decline. This study is published online in the Clinical Journal of the American Society of Nephrology on March 18, 2010.

“High consumption of animal protein has been reported to promote kidney damage in previous studies.,” said Julie Lin MD, MPH, of the Renal Division at BWH. “This prompted the investigation to examine associations between several individual dietary nutrients and kidney function.” The researchers studied how nutrient intake data affected urinary albumin levels and change in estimated glomerular filtration rate (eGFR) over 11 years in more than 3,000 women participating in the Nurses' Health Study. The team looked at how various proteins, fats, cholesterol, fiber, antioxidant vitamins, vitamin D, folate, fructose, sodium, and potassium were associated with microalbuminuria and kidney function decline.

Higher dietary intake of animal protein, saturated and animal fat and cholesterol were associated with increased risk for microalbuminuria, defined as a low level of protein in the urine that is highly predictive of subsequent kidney and cardiovascular disease as well as all-cause mortality, even after adjusting for clinical conditions such as obesity, hypertension and diabetes. Specifically, study participants who consumed two or more servings of red meat per week had a nearly 50 percent greater risk for presence of microalbuminuria when compared to those consuming less than one serving per week.

The study also reported that diets lower in sodium but higher in beta carotene (abundant in green leafy and root vegetables) may be protective against eGFR decline. No other significant associations were noted between the other dietary nutrients and microalbuminuria or eGFR decline. Dr. Lin said, “While further study is needed, our research suggests that dietary modification is a potentially important intervention in the prevention of progressive kidney function decline.”

The study was funded by grants from the National Institutes of Health.

Brigham and Women's Hospital (BWH) is a 777-bed nonprofit teaching affiliate of Harvard Medical School and a founding member of Partners HealthCare, an integrated health care delivery network. In July of 2008, the hospital opened the Carl J. and Ruth Shapiro Cardiovascular Center, the most advanced center of its kind. BWH is committed to excellence in patient care with expertise in virtually every specialty of medicine and surgery. The BWH medical preeminence dates back to 1832, and today that rich history in clinical care is coupled with its national leadership in quality improvement and patient safety initiatives and its dedication to educating and training the next generation of health care professionals. Through investigation and discovery conducted at its Biomedical Research Institute (BRI), BWH is an international leader in basic, clinical and translational research on human diseases, involving more than 860 physician-investigators and renowned biomedical scientists and faculty supported by more than $416 M in funding. BWH is also home to major landmark epidemiologic population studies, including the Nurses' and Physicians' Health Studies and the Women's Health Initiative. For more information about BWH, please visit http://www.brighamandwomens.org/.

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