Table 1

Baseline characteristics of participants overall and by baseline serum 25(OH)D levels in the HUNT2 survey, 1995–1997

Baseline seasonal-standardized serum
25(OH)D level (nmol/L)
CharacteristicOverall (N=3574)<50.0 (n=2059)≥50.0 (n=1515)
Age (years)46.6±13.445.7±12.947.9±14.1
BMI (kg/m²)26.0±3.826.6±4.125.3±3.3
Sex (female/male)54.7/45.354.4/45.655.0/45.0
Education (years: <10/10–12/≥13/unknown)29.5/36.9/31.2/2.530.6/37.5/28.9/3.027.9/36.0/34.3/1.8
Economic difficulties (no/yes/unknown)59.2/21.8/19.055.9/23.9/20.263.7/18.9/17.4
Smoking status (never/former/current/unknown)45.0/27.9/26.2/1.043.9/26.6/28.6/1.046.5/29.6/23.0/0.9
Alcohol intake per month (0 (abstainer)/1–4/≥5/unknown)29.4/51.4/12.0/7.231.6/50.9/10.4/7.026.4/52.1/14.2/7.3
Physical activity (inactive/low/moderate/high/unknown)20.8/18.7/25.0/9.0/26.523.3/19.1/22.3/7.4/27.917.3/18.2/28.5/11.3/24.7
Sitting time per day (hours: ≤4/5–7/≥8/unknown)26.7/24.6/30.3/18.426.0/23.2/30.3/20.527.6/26.5/30.4/15.5
Family history of diabetes (no/yes/unknown)69.9/16.2/13.868.5/15.9/15.671.9/16.6/11.4
PRS for T2DM (bottom 2/3/top 1/3/unknown)64.7/32.3/3.063.0/33.6/3.567.0/30.6/2.4
Chronic diseases (no/yes/unknown)70.6/26.7/2.671.4/26.1/2.569.6/27.7/2.8
  • Data are given as percentage (%) or mean±SD.

  • BMI, body mass index; HUNT, Trøndelag Health Study; 25(OH)D, 25-hydroxyvitamin D; PRS, polygenic risk score; T2DM, type 2 diabetes mellitus.