Table 4 Subgroup analysis of association between dietary inflammatory index (DII) and bone mineral density (BMD) by BMI groups among adults

Underweight

DII continuous

0.001 (− 0.012,0.014)

0.859

 − 0.001 (− 0.009, 0.007)

0.760

0.001 (− 0.006, 0.008)

0.792

DII tertile

 Tertile 1

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 Tertile 2

0.06 (− 0.008,0.128)

0.081

0.041 (− 0.010, 0.093)

0.105

0.047 (0.003, 0.090)

0.038

 Tertile 3

 − 0.022 (− 0.081,0.037)

0.447

 − 0.023 (− 0.077, 0.030)

0.362

 − 0.017 (− 0.060, 0.026)

0.415

Normal weight

DII continuous

 − 0.001 (− 0.005,0.003)

0.713

 − 0.002 (− 0.005, 0.001)

0.152

 − 0.001 (− 0.005, 0.002)

0.369

DII tertile

 Tertile 1

Ref

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 Tertile 2

0.013 (− 0.004,0.030)

0.124

0.005 (− 0.008, 0.018)

0.465

0.007 (− 0.006, 0.020)

0.298

 Tertile 3

 − 0.009 (− 0.028,0.010)

0.364

 − 0.013 (− 0.027, 0.002)

0.099

 − 0.009 (− 0.024, 0.007)

0.262

Overweight

DII continuous

 − 0.007 (− 0.010, − 0.004)

 < 0.001

 − 0.005 (− 0.007, − 0.002)

 < 0.001

 − 0.005 (− 0.007, − 0.002)

0.002

DII tertile

 Tertile 1

Ref

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 Tertile 2

 − 0.011 (− 0.024, 0.001)

0.080

 − 0.009 (− 0.021, 0.002)

0.109

 − 0.009 (− 0.021, 0.002)

0.111

 Tertile 3

 − 0.035 (− 0.051, − 0.020)

 < 0.001

 − 0.025 (− 0.037, − 0.013)

 < 0.001

 − 0.024 (− 0.036, − 0.011)

 < 0.001

Obese

DII continuous

 − 0.006 (− 0.010, − 0.003)

 < 0.001

 − 0.006 (− 0.009, − 0.002)

0.002

 − 0.005 (− 0.008, − 0.002)

0.005

DII tertile

 Tertile 1

Ref

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 Tertile 2

 − 0.009 (− 0.025, 0.007)

0.250

 − 0.01 (− 0.022, 0.003)

0.129

 − 0.009 (− 0.021, 0.004)

0.161

 Tertile 3

 − 0.02 (− 0.035, − 0.005)

0.012

 − 0.017 (− 0.033, − 0.002)

0.027

 − 0.015 (− 0.030, 0.000)

0.049