Healthy diets may lower risk of kidney disease

Following a healthy dietary pattern focusing on plant-based food and reduced intake of red meat is associated with a lower risk of developing end-stage kidney disease (ESKD) among Chinese adults, with the greatest benefit seen in obese or overweight people, according to the Singapore Chinese Health Study.

The prospective population-based cohort study included 56,985 Chinese adults aged 45–74 years who were free of stroke, coronary artery disease, cancer, and ESKD at baseline. [Am J Clin Nutr 2020;doi:10.1093/ajcn/nqaa348]

After a median follow-up of 17.5 years, 1,026 participants had developed ESKD, based on data from the Singapore Renal Registry.

For all three dietary patterns analysed (ie, AHEI-2010, DASH, and aMED*), stricter adherence to these diets — as indicated by higher scores — was associated with a lower ESKD risk.      

The risk of ESKD was 25 percent lower in participants in the highest score quintile for AHEI-2010 (adjusted hazard ratio [aHR], 0.75; p-trend=0.001), 33 percent lower for DASH (aHR, 0.67; p-trend<0.001), and 27 percent lower for aMED (aHR, 0.73; p-trend=0.004), compared with the lowest score quintile for each dietary pattern.

When analysed by diet component, the researchers found that the association was mainly driven by reduced intake of red meat, regardless of fresh or processed, and increased intake of nuts and legumes.

In addition, individuals with higher BMI appeared to benefit more from following a healthy diet, with stronger inverse association with increasing BMI. The extent of reduction in ESKD risk was greatest in those who were obese (BMI ≥27.5; aHRs, 0.79, 0.81, and 0.75 for AHEI-2010, DASH, and aMED, respectively, per 1-standard deviation increment in diet scores), compared with those in lower categories of BMI.

“It is possible that the inverse association between a high-quality diet and risk of ESKD could be partially mediated by the reduction in BMI or the reduced development of diabetes in those with higher dietary scores during follow-up,” according to the researchers led by Professor Koh Woon-Puay of Duke-NUS Medical School, Singapore.

These findings, based on an Asian population, were consistent with previous studies on Western populations, which also found that following healthy diets such as DASH, AHEI-2010, and Mediterranean diet was associated with a reduced risk of kidney function decline.

“The three healthful dietary patterns examined in our study have considerable overlap and emphasize higher intake of healthy plant-based foods, such as nuts, legumes, vegetables, and fruits, and lower intake of red meat (fresh or processed),” explained Koh and co-authors.

“Intake of sugar-sweetened beverages and fruit juice, as well as sodium intake, was restricted in addition in AHEI-2010 and DASH,” they added.

“Our findings highlight the importance of public health and clinical programs targeting promotion of an overall healthful diet to reduce the risk of severe kidney disease in the general population.”

*AHEI-2010: Alternate Healthy Eating Index-2010; DASH: Dietary Approaches to Stop Hypertension; aMED: alternate Mediterranean diet