Table 3 The results of multiple linear regression analysis for the association between total flavonoids intake and differences in biological age (BA) with chronological age (CA)

Total flavonoid intake

 Q1

Ref.

–

Ref.

–

Ref.

–

Ref.

–

 Q2

 − 0.73 (− 1.30, − 0.16)

0.01

 − 0.38 (− 1.36, 0.60)

0.43

 − 1.02 (− 2.62, 0.59)

0.21

 − 4.59 (− 7.38, − 1.81)

 < 0.01

 Q3

 − 1.33 (− 1.95, − 0.71)

 < 0.01

 − 1.51 (− 2.32, − 0.70)

 < 0.01

 − 1.07 (− 2.66, 0.52)

0.18

 − 5.14 (− 7.77, − 2.50)

 < 0.01

Sex

 Male

Ref.

–

Ref.

–

Ref.

–

Ref.

–

 Female

 − 2.92 (− 3.29, − 2.54)

 < 0.01

 − 1.92 (− 2.63, − 1.21)

 < 0.01

 − 13.79 (− 14.67, − 12.91)

 < 0.01

8.66 (6.64, 10.68)

 < 0.01

Age (years)

 ~ 30

1.43 (0.80, 2.06)

 < 0.01

1.74 (0.73, 2.75)

 < 0.01

3 (1.35, 4.66)

 < 0.01

 − 2.14 (− 4.94, 0.67)

0.13

 30–59

 − 0.41 (− 0.98, 0.15)

0.15

 − 0.11 (− 1.18, 0.96)

0.84

 − 0.23 (− 1.30, 0.85)

0.67

1.47 (− 0.77, 3.71)

0.19

  ≥ 60

Ref.

–

Ref.

–

Ref.

–

Ref.

–

Healthy behavior factors

 Smoke status

  Current smokers

1.43 (0.99, 1.88)

 < 0.01

0.74 (− 0.08, 1.57)

0.08

 − 0.22 (− 1.82, 1.37)

0.02

5.71 (2.58, 8.84)

 < 0.01

  No smoke

Ref.

–

Ref.

–

Ref.

–

Ref.

–

 Drinking

  No drink user

Ref.

–

Ref.

–

Ref.

–

Ref.

–

  Former

0.01 (− 0.79, 0.80)

0.99

 − 0.15 (− 1.62, 1.32)

0.83

1.21 (− 0.59, 3.01)

0.18

 − 3.32 (− 7.83, 1.18)

0.14

  Mild

 − 1.15 (− 1.78, − 0.52)

 < 0.01

 − 1.64 (− 2.82, − 0.46)

0.01

3.1 (1.61, 4.60)

 < 0.01

 − 11.27 (− 14.59, − 7.95)

 < 0.01

  Moderate

 − 1.07 (− 1.80, − 0.34)

0.01

 − 1.32 (− 2.66, 0.01)

0.05

0.77 (− 0.84, 2.38)

0.34

 − 6.61 (− 10.37, − 2.85)

 < 0.01

  Heavy

1.12 (0.27, 1.97)

0.01

0.94 (− 0.34, 2.22)

0.14

4.97 (2.96, 6.98)

 < 0.01

 − 5.28 (− 9.47, − 1.10)

0.02

 Physical activity level

  Never

Ref.

–

Ref.

–

Ref.

–

Ref.

–

  Low

 − 1.31 (− 2.00, − 0.61)

 < 0.01

 − 0.87 (− 2.05, 0.31)

0.14

 − 0.93 (− 2.40, 0.55)

0.21

 − 7.76 (− 11.12, − 4.39)

 < 0.01

  Intermediate

 − 1.29 (− 1.99, − 0.58)

 < 0.01

 − 0.81 (− 1.94, 0.32)

0.15

0.2 (− 1.40, 1.80)

0.80

 − 13.32 (− 16.41, − 10.22)

 < 0.01

  High

0.16 (− 0.69, 1.01)

0.70

0.59 (− 0.70, 1.87)

0.36

2.39 (0.94, 3.84)

0.002

 − 8.74 (− 11.60, − 5.87)

 < 0.01

 Chronic disease factors

  BMI, kg/m²

  BMI < 25

Ref.

–

Ref.

–

Ref.

–

Ref.

–

  BMI ≥ 25

2.25 (1.70, 2.80)

 < 0.01

3.17 (2.43, 3.91)

 < 0.01

5.78 (4.68, 6.87)

 < 0.01

11.78 (9.45, 14.11)

 < 0.01

 Hypertension

  No Hypertension

Ref.

–

Ref.

–

Ref.

–

Ref.

–

  Hypertension

3.35 (2.87,3.83)

 < 0.01

5.26 (4.51, 6.01)

 < 0.01

3.88 (2.74, 5.01)

 < 0.01

5.89 (3.63, 8.16)

 < 0.01

 Diabetes

  No diabetes

Ref.

–

Ref.

–

Ref.

–

Ref.

–

  Diabetes

2.99 (2.42, 3.56)

 < 0.01

4.3 (3.56, 5.05)

 < 0.01

2.16 (1.00, 3.32)

 < 0.01

5.71 (3.14, 8.28)

 < 0.01

 Chronic kidney disease

  No CKD

Ref.

–

Ref.

–

Ref.

–

Ref.

–

  CKD

4.06 (3.19, 4.92)

 < 0.01

3.16 (1.73,4.59)

 < 0.01

8.03 (5.85, 10.21)

 < 0.01

6.98 (3.75, 10.20)

 < 0.01