Table 1 Baseline characteristics of study participants

Age, years, mean (SD)

42 (13)

45 (13)

37 (11)

Sex, n (%)

 - Male

10 (19)

5 (14)

5 (29)

 - Female

43 (81)

31 (86)

12 (71)

Ethnicity, n (%)*

 - Maori

14 (26)

10 (28)

4 (24)

 - Pacific

18 (34)

8 (22)

10 (59)

 - New Zealand European

23 (43)

19 (53)

4 (24)

 - Other

9 (17)

5 (14)

4 (24)

Highest educational qualification, n (%)

 - School certificate

20 (38)

12 (33)

8 (47)

 - University or polytechnic degree or diploma

30 (57)

23 (64)

7 (41)

 - Other

3 (6)

1 (3)

2 (12)

Annual household income before tax, n (%)

 - ≤$50,000

11 (21)

8 (22)

3 (18)

 - $50,001 to $100,000

25 (47)

16 (44)

9 (53)

 - ≥$100,001

14 (26)

10 (28)

4 (23)

 - Decline to answer

3 (6)

2 (6)

1 (6)

Body weight, kg, mean (SD)

100.9 (21.3)

99.8 (21.7)

103.3 (20.9)

BMI, kg/m², mean (SD)

35.7 (6.8)

35.4 (7.1)

36.3 (6.3)

Systolic blood pressure, mmHg, mean (SD)

121.8 (16.9)

123.4 (16.2)

118.4 (18.4)

Diastolic blood pressure, mmHg, mean (SD)

75.6 (11.2)

76.0 (11.1)

74.7 (11.6)

Diagnosed co-existing conditions, n (%)*

 - Diabetes

6 (11)

6 (17)

0 (0)

 - High blood pressure

10 (19)

8 (22)

2 (12)

 - High blood cholesterol

5 (9)

3 (8)

2 (12)

 - Coronary heart disease or stroke

2 (4)

2 (6)

0 (0)

 - Osteoarthritis

4 (8)

3 (8)

1 (6)

Smoking status, n (%)

 - Current smoker

5 (9)

2 (6)

3 (18)

 - Ex-smoker

21 (40)

15 (42)

6 (35)

 - Never smoked

27 (51)

19 (53)

8 (47)

Usual alcohol intake, n (%)

 - Never

9 (17)

5 (14)

4 (24)

 - Once a week or less

34 (64)

22 (61)

12 (70)

 - 2-3 times per week

8 (15)

7 (19)

1 (6)

 - 4 times or more per week

2 (4)

2 (6)

0 (0)

Sleep, n (%)

 - Weekday or workday night, hours, mean (SD)

6.6 (1.1)

6.7 (1.0)

6.5 (1.1)

 - Weekend or non-work night, hours, mean (SD)

7.3 (1.2)

7.4 (1.1)

7.1 (1.4)

Self-reported knowledge of weight loss and dieting, n (%)

 - None

1 (2)

1 (3)

0 (0)

 - Little

12 (23)

8 (22)

4 (24)

 - Moderate amount

21 (40)

15 (42)

6 (35)

 - A lot

19 (36)

12 (33)

7 (41)

Weight loss history, n (%)

 - Previously tried to lose weight, n (%)

49 (92)

33 (92)

16 (94)

 - Number of weight loss attempts in past 5 years

  ○ One

10 (20)

8 (24)

2 (13)

  ○ 2-4

19 (39)

13 (39)

6 (38)

  ○ 5 or more

18 (37)

11 (33)

7 (44)

 - Methods used*

  ○ Changing food intake, n (%)

42 (86)

29 (88)

13 (81)

  ○ Doing more exercise, n (%)

47 (96)

32 (97)

15 (94)

  ○ Use of laxatives and/or diuretics, n (%)

3 (6)

1 (3)

2 (13)

  ○ Prescribed weight loss medication, n (%)

5 (10)

4 (12)

1 (6)

  ○ Over-the-counter weight loss treatment, n (%)

6 (12)

6 (18)

0 (0)