Healthy adult vegetarians have better renal function than matched omnivores: a cross sectional study in China.

Abstract

Background Appropriate diet is an important determinant of kidney health. However, the association between vegetarian diets and renal function is unclear. Object We aimed to study the association between vegetarian diets and renal function in healthy adults. Design A total of 269 vegetarians (aged 34.5±8.7 years) and 269 sex- and age-matched nonvegetarian omnivores were enrolled in this cross-sectional study. Basic characteristics as well as daily dietary intakes were assessed by face-to-face interviews. Blood samples were collected, and renal function was assessed by measuring blood urea nitrogen (BUN), creatinine (Cr), uric acid (UA) and estimated glomerular filtration rate (eGFR). Blood pressure, fasting blood glucose and blood lipid profiles were also assessed. Results The average age of the vegetarians was 35.4±8.6 years, 82.2% of whom were female. We evaluated the association between vegetarian diets and renal function by using multivariate analysis. Compared with omnivores, vegetarians had lower BUN (β= -0.63, 95% CI: -0.88 to -0.38), SCr (β= -2.07, 95% CI: -4.21 to -0.061), UA (β= -15.17, 95% CI: -27.81 to -2.53) and higher eGFR levels (β= 4.09, 95% CI: 0.23 to 7.96) after adjusting for sex, age, BMI, physical activity, alcohol consumption, smoking status, LDL, HDL, systolic pressure and fasting blood glucose. Further analysis of food composition and renal function showed that dietary fiber intake was significantly negatively associated with BUN [β= -0.02, 95% CI:(-0.03, 0.00)], SCr [β= -0.14, 95% CI:(-0.25, 0.04)], and UA [β= -0.72, 95% CI:(-1.36, 0.07)] and positively associated with eGFR [β= 0.20, 95% CI:(0.00, 0.40)]. Conclusions Healthy adult vegetarians have better renal function than omnivores, and the higher dietary fiber intake associated with vegetarian diets may contribute to the protective effect on renal function.