People with kidney disease who regularly consumed foods familiar to Southern diets had a 50% increase in risk of death across the 6.5-year follow-up period.
Lifestyle factors that the National Kidney Foundation say can reduce kidney disease risk include eating a healthy diet, quitting smoking, taking regular exercise and maintaining a healthy weight.
Investigating the influence of diet on kidney disease patients, the researchers used the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study to identify 3,972 participants with stage 3-5 chronic kidney disease who had not started dialysis.
Analyzing the dietary habits of the participants, the researchers found that those who regularly consumed foods familiar to Southern diets had a 50% increase in risk of death across the 6.5-year follow-up period.
Foods that the authors identify as being part of a Southern diet include processed and fried foods, organ meats and sweetened beverages.
Previous studies have looked at the effect of individual nutrients on longevity in kidney patients, but this is the first research to focus on dietary patterns.
Lead author Dr. Orlando Gutiérrez, associate professor of Medicine at the University of Alabama at Birmingham, says:
"This is the first study to identify a regionally specific diet pattern that is highly associated with adverse outcomes among persons with kidney disease.
The influence of diet on health outcomes in the Southern region may already be known, but the study also reported one surprising finding.
- 1 in 3 American adults is at high risk for developing kidney disease today. The risk increases to 1 in 2 over the course of a lifetime.
- High blood pressure, diabetes, a family history of kidney failure and being over 60 are major risk factors for developing kidney disease.
- 1 in 9 American adults has kidney disease - and most do not know it.
- Early detection and treatment can slow or prevent the progression of kidney disease.
A healthy diet of whole foods, fruits and vegetables is known to be associated with improved survival, but in this study the healthy diet had no protective influence over kidney failure.
"This doesn't mean that eating a healthy diet doesn't help, but it suggests that healthy lifestyle overall - not smoking, exercising and eating right - the combination of these things is more important for kidney health," says Dr. Gutiérrez.
In 2013, Medical News Today reported on other research from the REGARDS study, which found that the Southern diet also increases risk of stroke.
The researchers behind that study found that people who ate Southern-type food at least six times a week had a 41% higher stroke risk than the rest of the population.
However, in that study, people who ate fruits, vegetables and whole grains at least five times a week were 29% less likely to have a stroke, compared with people who ate these foods less than three times a week.
The researchers commented that African-Americans are particularly at risk, noting that the Southern diet is around five times more popular among black people than the rest of the population.