Associations of healthy eating patterns with biological aging: national health and nutrition examination survey (NHANES) 1999-2018

Abstract

Background: Healthy dietary patterns have been negatively associated with methylation-based measures of biological age, yet previous investigations have been unable to establish the relationship between them and biological aging assessed through blood chemistry-based clinical biomarkers. We sought to assess the associations of 4 dietary metrics with 4 measures of biological age.

Methods: Among 16,666 participants in NHANES 1999-2018, 4 dietary metrics [Dietary inflammatory index (DII), Dietary approaches to stop hypertension index (DASH), Alternate mediterranean diet score (aMED), and Healthy eating index-2015 (HEI-2015)] were calculated through the 'dietaryindex' R package. Twelve blood chemistry parameters were utilized to compute 4 indicators of biological age [homeostatic dysregulation (HD), allostatic load (AL), Klemera-Doubal method (KDM), and phenotypic age (PA)]. Binomial logistic regression models and restricted cubic spline (RCS) regression were employed to evaluate the associations.

Results: All 4 dietary metrics were significantly associated with biological age acceleration or deceleration. In comparison to the lowest DII, the odds ratios (ORs) for accelerated HD, AL, KDM, and PA were 1.25 (1.08,1.45), 1.29 (1.11,1.50), 1.34 (1.08,1.65), and 1.61 (1.39,1.87) for the highest. The multivariable-adjusted ORs of the highest quartile of DASH, aMED, and HEI-2015 were 0.85 (0.73,0.97), 0.88 (0.74,1.04), and 0.84 (0.74,0.96) for HD, 0.64 (0.54,0.75), 0.61 (0.52,0.72), and 0.70 (0.59,0.82) for AL, 0.68 (0.54,0.85), 0.62 (0.50,0.76), and 0.71 (0.58,0.87) for KDM, and 0.50 (0.42,0.59), 0.64 (0.54,0.76), and 0.51 (0.44,0.58) for PA when compared with the lowest level. The findings were validated by the best-fitting dose-response curves for the associations. Among participants consuming dietary supplements (P_interaction < 0.05), the positive effects of a healthy dietary pattern on biological aging were more pronounced. Systemic immune inflammation index (SII) and atherogenic index of plasma (AIP) were identified as being involved in and mediating the associations.

Conclusions: Biological aging assessed through blood chemistry-based clinical biomarkers is negatively associated with diet quality. The anti-aging benefits of improving the diet may be due to its ability to reduce inflammation and lower blood lipids.

Keywords: Biological age; Biological aging; Dietary metrics; Healthy eating patterns; National Health and Nutrition Examination Survey (NHANES).

Fig. 1

Step-by-step diagram depicting the methodology for participant selection

Fig. 2

Associations of dietary metrics with accelerated HD, AL, KDM, and PA. The adjustments involved age, sex, ethnicity, year, BMI, smoking, exercise, education, income, nutrient supplement use, self-reported cancer, cardiovascular diseases, hypertension, diabetes, and chronic kidney disease. Models for DASH and HEI-2015 were additionally adjusted for drinking. Case/N, the number of case subjects/total. Q, quintile

Fig. 3

Smoothing curves between dietary metrics and accelerated HD, AL, KDM, and PA. Binomial logistic regression models and RCS were performed with adjusting for age, sex, ethnicity, year, BMI, smoking, exercise, education, income, nutrient supplement use, self-reported cancer, cardiovascular diseases, hypertension, diabetes, and chronic kidney disease. Models for DASH and HEI-2015 were additionally adjusted for drinking. The solid black lines correspond to the central estimates, and the gray-shaded regions indicate the 95% confidence intervals

Fig. 4

Effects mediated by SII and AIP on the relationships. The results were presented as standardized regression coefficients after adjusting for the covariates in the full model of binomial logistic regression. *P < 0.05, **P < 0.01, ***P < 0.001