Table 3 Weighted mean and standard error of total sustainable diet index-US (SDI-US), sub-index, and individual indicator scores by sustainable diet index-US quintile, US adults, NHANES 2007–2018

Median total SDI-US score (min, max)

9.7

(4.3, 10.8)

11.7

(11.0, 12.5)

13.0

(12.5, 13.7)

14.4

(13.8, 15.2)

16.1

(15.3, 20.0)

13.1

(4.3, 20.0)

NA

Weighted mean (standard error)^a

Total SDI-US score

9.5 ± 0.02

11.7 ± 0.01

13.1 ± 0.01

14.5 ± 0.01

16.5 ± 0.02

13.1 ± 0.04

1.00

Sub-Index Scores & Indicator Values

Nutritional

2.1 ± 0.03

2.6 ± 0.03

3.0 ± 0.03

3.4 ± 0.03

4.0 ± 0.02

3.1 ± 0.02

0.54^**

 Nutrient Rich Foods 9.3 index score

5.8 ± 0.3

11.2 ± 0.4

16.7 ± 0.5

22.0 ± 0.5

32.9 ± 0.6

18.1 ± 0.3

0.42^**

 Mean nutrient adequacy ratio

63.4 ± 0.3

67.7 ± 0.3

70.9 ± 0.3

73.9 ± 0.3

77.9 ± 0.2

71.0 ± 0.2

0.43^**

Environmental

2.2 ± 0.03

2.6 ± 0.03

2.9 ± 0.03

3.1 ± 0.04

3.6 ± 0.02

2.9 ± 0.01

0.39^**

 Fresh water use (L)

518 ± 8

444 ± 10

387 ± 8

337 ± 9

242 ± 5

382 ± 4

-0.27^**

 Stress-weighted water use (L)

17,275 ± 288

14,735 ± 326

13,244 ± 273

11,637 ± 309

8676 ± 175

13,004 ± 144

-0.26^**

 Acidifying emissions (g SO₂eq)

37.5 ± 0.6

28.8 ± 0.7

22.1 ± 0.4

18.6 ± 0.5

12.0 ± 0.3

23.5 ± 0.3

-0.38^**

 Eutrophying emissions (g PO₄³⁻eq)

29.9 ± 0.5

23.2 ± 0.6

17.0 ± 0.4

14.3 ± 0.5

8.7 ± 0.2

18.3 ± 0.2

-0.34^**

 Greenhouse gas emissions (kg CO₂eq)

7.0 ± 0.2

5.4 ± 0.2

3.9 ± 0.1

3.2 ± 0.1

2.0 ± 0.1

4.2 ± 0.1

-0.32^**

 Land use (m²)

17.4 ± 0.5

13.0 ± 0.5

8.7 ± 0.3

7.0 ± 0.3

3.7 ± 0.1

9.8 ± 0.2

-0.28^**

Economic

2.0 ± 0.03

2.7 ± 0.03

3.2 ± 0.03

3.7 ± 0.03

4.3 ± 0.02

3.2 ± 0.02

0.61^**

 Share of budget to food (%)

47.7 ± 1.5

30.4 ± 1.0

22.7 ± 0.9

17.4 ± 0.9

10.0 ± 0.2

25.1 ± 0.6

-0.27^**

Sociocultural

3.3 ± 0.02

3.8 ± 0.02

4.0 ± 0.02

4.2 ± 0.02

4.5 ± 0.01

4.0 ± 0.01

0.47^**

 Frequency of meals from a fast-food or pizza place (times during the last 7 days)

3.1 ± 0.1

2.0 ± 0.1

1.6 ± 0.1

1.1 ± 0.1

0.8 ± 0.04

1.7 ± 0.03

-0.32^**

 Frequency of ready-to-eat products

(times during the last 30 days)

3.6 ± 0.1

2.5 ± 0.2

1.9 ± 0.1

1.3 ± 0.1

0.8 ± 0.1

2.0 ± 0.1

-0.18^**

 Frequency of frozen meals and pizza

(times during the last 30 days)

5.1 ± 0.2

2.9 ± 0.1

2.6 ± 0.2

1.9 ± 0.1

1.3 ± 0.1

2.7 ± 0.1

-0.19^**

Index scores after removing each sub-index

SDI-US without nutritional sub-index

7.5 ± 0.03

9.1 ± 0.03

10.1 ± 0.03

11.0 ± 0.03

12.4 ± 0.02

10.1 ± 0.02

0.85^**

SDI-US without environmental sub-index

7.3 ± 0.03

9.1 ± 0.03

10.2 ± 0.03

11.3 ± 0.04

12.8 ± 0.03

10.2 ± 0.04

0.85^**

SDI-US without economic sub-index

7.6 ± 0.02

9.0 ± 0.03

9.9 ± 0.03

10.8 ± 0.03

12.1 ± 0.03

9.9 ± 0.03

0.83^**

SDI-US without sociocultural sub-index

6.3 ± 0.03

7.9 ± 0.02

9.1 ± 0.02

10.2 ± 0.02

12.0 ± 0.02

9.2 ± 0.03

0.93^**