New research links consumption of nuts 1-6 times per week with lower risks of chronic kidney disease (CKD) and all-cause mortality.
Among 6072 adults who participated in the 2003-2006 National Health and Nutrition Examination Survey (NHANES) and completed food frequency questionnaires, 284, 273, 594, 46, and 6 adults had CKD stage 1, 2, 3, 4, and 5, respectively. The remaining 4869 participants had no CKD.
Compared with no nut consumption, eating nuts 1-6 times per week (but not more than once daily) was significantly associated with 33% lower odds of developing CKD and 37% lower odds of all-cause mortality among those with CKD, Ying Yao, MD, and colleagues of Tongji Hospital, Wuhan, China, reported in the American Journal of Nephrology.
Increasing nut consumption also was significantly associated with lower all-cause mortality in the non-CKD population.
No reductions in cardiovascular mortality risk were observed in a fully adjusted model.
Nuts contain many nutrients and healthy compounds, including unsaturated fatty acids, vegetable protein, fiber, phytosterols, vitamins, minerals, and phenols, the investigators explained. However, nuts are also rich in protein, potassium, and phosphorus, which are restricted in advanced CKD. According to Dr Yao’s team, whether nuts should be incorporated into nutritional therapy for nondialysis-dependent CKD requires further study. They also noted that different nut types may have different effects. Some types may be more suitable for patients with CKD.
“In general, ‘1–6 times per week’ rather than a higher frequency might be an appropriate choice, in which nuts could continue their good work without causing any complications,” the investigators wrote. “More rigorously designed studies are needed to confirm this conclusion.”
Nuts are a good source of folate. A 30-year longitudinal study, published in the American Journal of Clinical Nutrition, looked at folate intake in early adulthood and the risk for CKD in midlife. In the CARDIA (Coronary Artery Risk Development in Young Adults) study, Xianhui Qin, MD, of Nanfang Hospital, Guangzhou, China and colleagues followed 4038 adults aged 18-30 years and free of CKD at baseline from 1985 to 2016. Using data from dietary history questionnaires, the investigators stratified patients into quintiles of folate intake.
After multivariable adjustment, the risk of new-onset CKD was 31%, 65%, 66%, and 61% lower for patients in quintiles 2, 3, 4, and 5 of folate intake respectively, compared with the lowest quintile.
“Higher folate intake in young adulthood was longitudinally associated with a lower incidence of CKD later in life,” the investigators concluded. Dietary sources of folate include green leafy vegetables, whole grains, fruits, other vegetables, nuts, seeds, and legumes.
Wang K, Qian D, Hu Y, Cheng Y, Ge S, Yao Y. Nut consumption and effects on chronic kidney disease and mortality in the United States. Am J Nephrol. Published online May 24, 2022. doi:10.1159/000524382
Liu M, Ye Z, Wu Q, et al. Folate intake and incident chronic kidney disease: a 30-y follow-up study from young adulthood to midlife. Am J Clin Nutr. Published online April 23, 2022. doi:10.1093/ajcn/nqac109