A group of investigators, led by Alex Chang, MD, of Johns Hopkins University, discovered that people with regular kidneys whose diet quality was bad - high in processed and red meats, sodium, and sugar-sweetened beverages, and low in fruit, nuts, legumes, whole grains, and low-fat dairy - were more likely to develop kidney disease.
Just one percent of people without unhealthy diet or lifestyle choices developed protein in their urine - an early sign of kidney damage. On the other hand, 13% of participants who had at least three unhealthy factors such as obesity, smoking, and poor diet developed protein in their urine.
Obese people, i.e. those with a body mass index (BMI) of at least 30, were twice as likely to develop kidney disease, the authors reported. A poor diet independently influenced risk for chronic kidney disease after adjusting for weight and other influential factors.
The investigators also pinpointed a link between those who currently smoke and the development of chronic kidney disease. Smokers were found to be 60% more likely to develop kidney disease.
In the first study conducted on this topic, researchers analyzed kidney disease risk factors in healthy young people using longitudinal data ranging over 15 years, including information on more than 2,300 black and white adults aged between 28 and 40 years from the Coronary Artery Risk Development in Young Adults (CARDIA) Study.
Dr. Chang said:
"Unlike family history of kidney disease, diet, smoking, and obesity are modifiable lifestyle factors that we can all control. By eating well, quitting smoking, and maintaining a normal weight, people can protect their kidneys and prevent future damage."
In total, those who ended up with kidney disease were more likely...
- to be African American
- to have high blood pressure
- to have diabetes
- to have a family history of kidney disease
- have a higher intake of soft drinks, fast food, and red meat
Dr. Beth Piraino, National Kidney Foundation President explained:
"In the United States, 26 million adults are living with chronic kidney disease. We need to shift the focus from managing chronic kidney disease to preventing it in the first place. Using this study as evidence, we can encourage changes in individual lifestyle choices and behaviors, and ultimately prevent people from developing kidney disease."
The National Kidney Foundation has the following guidelines to reduce the risk of developing kidney disease:
- Reduce sodium intake: Americans consume too much sodium (salt)
- Limit red meat: Diets high in protein - especially those with animal protein - may harm the kidneys. Red meat is also high in saturated fat.
- Avoid soda: Sugar-sweetened drinks, like sodas, are high in calories and contain no nutritious value. Additionally, colas have phosphorus additives which can damage kidneys.
- Give up processed foods: Potato chips, crackers, cheese spreads, instant potato mix, and deli meats are all examples of processed foods that are high in phosphorus additives and sodium - both of which can have a damaging effect on the kidneys.
- Reduce sugar intake: Consuming too much sugar can result in diabetes or obesity - both linked to kidney disease.
A previous study from 2009 stated that obese people with prehypertension are at an increased risk for kidney disease.