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. 2025 Sep 30;44:343. doi: 10.1186/s41043-025-01080-1

Table 2.

The averages of biological age (BA) and its differences with chronological age (CA) by tertile of the dietary inflammatory index (DII), NHANES 1999–2018

Variables Heart BA Heart BA difference (BA-CA) Liver BA Liver BA difference (BA-CA) Kidney BA Kidney BA difference (BA-CA)
Mean (SD) P Mean (SD) P Mean (SD) P Mean (SD) P Mean (SD) P Mean (SD) P
DII 44.98(19.89) -0.61(11.58) 43.26(28.48) -2.33(23.26) 45.09(19.09) -0.50(11.20)
DIIQ 0.97 < 0.01 < 0.01 < 0.01 0.04 0.34
Q1 44.97(18.42) -1.55(11.34) 39.79(27.22) -6.74(21.93) 45.83(17.58) -0.70(10.06)
Q2 45.06(19.97) -0.30(11.37) 43.76(28.59) -1.60(23.09) 45.10(18.89) -0.26(10.75)
Q3 44.91(21.44) 0.19(12.00) 46.88(29.35) 2.16(24.04) 44.18(20.94) -0.54(12.84)
Age (years) < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
< 30 22.73(9.14) -0.62(8.59) 19.39(23.93) -3.96(23.54) 25.15(9.07) 1.80(8.59)
30–60 44.91(14.91) -0.05(11.80) 43.56(24.60) -1.39(23.45) 43.64(12.77) -1.32(10.27)
≥ 60 65.91(13.92) -1.91(13.26) 64.80(22.86) -3.02(22.41) 67.08(15.54) -0.73(14.62)
Sex 0.12 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
 female 44.64(21.10) -1.67(11.43) 50.51(25.69) 4.19(22.63) 43.42(18.64) -2.90(10.60)
 male 45.34(18.51) 0.52(11.63) 35.58(29.27) -9.24(21.88) 46.85(19.40) 2.03(11.25)
Education lever < 0.01 < 0.01 < 0.01 < 0.01 0.17 0.09
college or higher 43.52(18.93) -1.57(11.03) 41.54(27.61) -3.55(22.52) 44.75(18.54) -0.34(10.85)
high school 46.85(21.10) 0.72(11.83) 45.05(29.10) -1.07(24.00) 45.54(19.33) -0.58(11.30)
below high school 48.06(21.14) 1.27(12.89) 47.50(30.36) 0.71(24.63) 45.76(20.84) -1.04 (12.35)
Race < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
Mexican 40.17(19.70) 0.83(11.03) 37.67(28.62) -1.67(22.76) 38.11(17.94) -1.23(10.85)
black 44.36(21.20) 1.83(12.62) 52.17(29.61) 9.64(25.50) 43.93(21.04) 1.40(14.18)
white 46.23(19.55) -1.26(11.38) 43.26(28.00) -4.23(22.34) 46.81(20.60) -0.68(10.65)
other Hispanic 42.32(20.06) 0.32(11.92) 41.45(28.07) -0.56(22.56) 41.57(17.79) -0.44(10.68)
other 41.97(19.68) -0.57(11.51) 37.83(28.09) -4.72(23.63) 41.64(18.17) -0.90(11.57)
PIR < 0.01 < 0.01 0.19 < 0.01 < 0.01 0.23
< 1 40.55(21.33) 0.85(12.06) 42.05(32.06) 2.35(26.02) 38.89(19.64) -0.81(11.87)
≥ 1 45.76(19.52) -0.86(11.47) 43.47(27.80) -3.15(22.64) 46.18(18.79 -0.45(11.07)
BMI (kg/m2) < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
< 25 38.15(19.88) -3.13(11.20) 33.74(28.85) -8.23(22.53) 38.84(19.04) -3.13(11.20)
≥ 25 48.22(19.06) 0.74(10.98) 47.77(27.16) 0.46(23.08) 48.05(18.39) 0.74(10.98)
Smoking < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
former 52.35(18.75) -0.57(11.98) 48.83(28.03) -4.09(22.99) 52.90(19.37) -0.02(12.96)
never 42.69(19.97) -0.98(11.22) 41.09(27.98) -2.58(22.75) 43.52(18.92) -0.16(11.11)
now 42.40(18.88) 0.30(11.96) 42.42(29.40) 0.31(24.57) 40.17(16.42) -1.93(10.09)
Drinking < 0.01 0.47 < 0.01 < 0.01 < 0.01 0.06
former 52.65(19.85) -0.29(13.41) 51.51(27.20) -1.42(23.03) 51.65(20.36) -1.28(13.16)
never 45.33(22.81) -0.33(11.74) 46.06(29.57) 0.40(23.30) 44.81(22.67) -0.84(14.44)
now 43.58(19.11) -0.70(11.22) 41.39(28.25) -2.89(23.26) 43.97(18.03) -0.31(10.23)
Physical activity < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 0.73
no 49.49(21.30) 0.27(12.70) 51.10(29.77) 1.88(24.71) 48.64(21.34) -0.58(13.29)
yes 43.38(19.11) -0.92(11.14) 40.47(27.48) -3.83(22.53) 43.82(18.06) -0.47(10.35)
Hypertension < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
no 37.04(16.24) -3.08(9.31) 36.92(26.94) -3.20(22.37) 39.00(15.93) -1.12(9.21)
yes 59.32(17.73) 3.85(13.74) 54.71(27.60) -0.75(24.70) 56.08(19.41) 0.62(14.02)
CKD < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
no 43.03(18.75) -1.04(10.66) 40.87(27.21) -3.20(22.43) 42.63(16.05) -1.43(8.83)
yes 59.35(22.04) 2.55(16.53) 60.85(31.33) 4.06(27.82) 63.14(27.96) 6.35(20.54)
DM < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
no 41.91(18.47) -1.68(10.37) 40.47(27.68) -3.12(22.70) 42.70(17.58) -0.88(10.01)
yes 64.06(17.64) 6.02(15.75) 60.58(27.23) 2.54(25.94) 59.91(21.30) 1.87(16.58)

BA: biological age; CA: chronological age; DII: dietary inflammatory index; CKD: Chronic kidney disease; DM: Diabetes mellitus; BMI: Body mass index; PIR: Poverty income ratio