Losing belly fat and cutting back consumption of phosphorus found in processed foods and dietary protein may reduce risk for developing kidney disease, according to a new study published in the November issue of the American Journal of Kidney Diseases. Researchers found that diminishing waist circumference and consuming less dietary phosphorus were linked with reduced levels of albuminuria, or protein in the urine.

"Other studies have suggested that once diagnosed with kidney disease, weight loss may slow kidney disease progression, but this is the first research study to support losing belly fat and limiting phosphorus consumption as a possible way to prevent kidney disease from developing," said Joseph Vassalotti, MD, Chief Medical Officer at the National Kidney Foundation.

(ASN disagrees with new guidelines, says adults should be screened for kidney disease)

Researchers led by Alex Chang, MD, MS of Johns Hopkins University, examined the association between weight loss, phosphorus intake and urine protein levels in 481 participants, based on the PREMIER study of lifestyle modifications in overweight-obese adults. After six months, on average, study participants decreased their belly fat by 4.2cm and experienced a 25% reduction in urine protein. Additionally, a 314 mg reduction in phosphorus excretion resulted in an 11% decrease in urine protein.

In the United States,phosphorus is added to many processed foods to help enhance their flavor and shelf life. High levels of phosphorus are also naturally found in animal, dairy, and vegetable proteins, according to Chang. Due to its chemical composition, the phosphorus found in processed foods – which accounts for up to 30% of the phosphorus consumed in the U.S. diet – as well as the phosphorus contained in animal proteins is more readily absorbed by the body than plant-based phosphorus, which is harder for humans to break down.

“A good rule of thumb is that if the food comes in a package, it’s likely to be high in phosphorus.  Approximately 90% of phosphorus additives are absorbed by the body. This study suggests limiting the amount of processed foods in your diet may be an easy way to reduce your risk of developing kidney disease," said Vassalotti.