Associations of macronutrient intake patterns with accelerated biological ageing and life expectancy: Evidence from a population-based study in the UK Biobank

BACKGROUND The associations of macronutrient intake with accelerated biological aging and life expectancy remain unclear. METHODS In total, 56,555 participants in the UK Biobank were included. Macronutrient intake patterns, including overall low-carbohydrate-diet (LCD), low-fat-diet (LFD), low-protein-diet (LPD), low-animal-protein diet (LAPD), low-vegetable-protein diet (LVPD), low-animal-fat diet (LAFD), low-vegetable-fat diet (LVFD), and healthful plant-based diet index (hPDI), were assessed via the Oxford WebQ. Klemera-Doubal-Method Biological Age acceleration (KDM-BA Accel) and PhenoAge acceleration (PhenoAge Accel) were computed to assess accelerated biological aging. Multivariable generalized linear regressions were conducted to estimate the β and 95% confidence intervals (CI). Life expectancy was assessed by proportional hazards survival analysis. RESULTS We observed consistent significant associations of overall LCD and LFD, but not LPD, with biological aging. However, overall macronutrient intake patterns were not related to life expectancy. Compared with the lowest tertile, adherence to the LLQCD, LAPD, LAFD and hPDI in the highest tertile were associated with decreases of -0.901 (95% CI: -1.025, -0.778), -0.762 (-0.888, -0.637), -0.996 (-1.121, -0.870), and -0.113 (-0.127, -0.099) KDM-BA-Accel years, and -0.847 (-0.933, -0.761), -0.497 (-0.585, -0.409), -0.950 (-1.038, -0.863), and -0.221 (-0.241, -0.200) PhenoAge-Accel years, as well as additional gains of 1.666 (1.039, 2.294), 1.538 (0.912, 2.164), 1.381 (0.757, 2.006), and 2.650 (2.007, 3.292) life years, respectively. Conversely, LHQCD, LVPD, and LVFD were associated with accelerated biological aging and shorten life expectancy. CONCLUSIONS This study demonstrates that the quality of macronutrient intake patterns may be more important than overall patterns in influencing biological aging and life expectancy.