Table 1.

Selected baseline characteristics of study participants

Intervention arms
All participantsPlaceboVitamin D
VariableNMean (SD)NMean (SD)NMean (SD)
Age, y21859.6 (5.1)10959.0 (4.7)10960.3 (5.3)
Weight (kg)21887.7 (16.3)10988.1 (17.1)10987.4 (15.5)
BMI (kg/m2)21832.4 (5.8)10932.5 (6.1)10932.3 (5.5)
Waist circumference (cm)218100.1 (12.3)109100.3 (13.5)109100.0 (11.0)
Body fat (%)21547.4 (4.9)10747.5 (4.5)10847.3 (5.2)
Moderate to vigorous physical activity (min/wk)218142.2 (143.2)109146.6 (140.4)109137.9 (146.5)
Caloric intake (kcal/d)a2062,004 (699.3)1031982 (678.4)1032,025 (722.3)
Relative % calories from fata20633.0 (6.2)10332.6 (5.7)10333.4 (6.7)
Relative % calories from proteina20617.6 (3.2)10317.9 (3.5)10317.2 (2.9)
Relative % calories from carbohydratea20648.3 (7.4)10348.1 (7.1)10348.5 (7.8)
Dietary vitamin D intake (μg)2066.6 (4.6)1036.9 (5.2)1036.3 (4.0)
Vitamin D supplement intake (IU) at baseline52280.0 (134.5)22303.6 (125.2)30262.7 (140.5)
Total calcium intake (mg)2081,120 (599.8)1031,170 (632.7)1051,071 (564.4)
Sun exposure (h/wk)2182.4 (1.3)1092.2 (1.3)1092.5 (1.3)
Serum 25(OH)D (ng/mL)21821.4 (6.1)10921.4 (6.1)10921.4 (6.2)
IL1β (pg/mL)2171.5 (10.4)1081.0 (3.0)1092.0 (14.4)
IL6 (pg/mL)2177.2 (19.8)1088.6 (27.2)1095.7 (7.1)
IL8 (pg/mL)21713.5 (64.9)1087.6 (5.1)10919.4 (91.2)
IL10 (pg/mL)21753.7 (386.6)10828.9 (33.2)10978.3 (544.5)
TNFα (pg/mL)21710.4 (4.7)10810.4 (4.8)10910.4 (4.6)
Adiponectin (μg/mL)21712.4 (6.1)10812.5 (6.4)10912.3 (5.9)
Leptin (ng/mL)21740.3 (18.9)10840.3 (17.4)10940.4 (20.5)
N (%)N (%)N (%)
Race/ethnicity
 Non-Hispanic white188 (86.2)94 (86.2)94 (86.2)
 Non-Hispanic Black13 (6.0)6 (5.5)7 (6.4)
 Hispanic5 (2.3)4 (3.7)1 (0.9)
 Other (American Indian, Asian, or Unknown)12 (5.5)5 (4.5)7 (6.4)
Medication useb
 Systemic corticosteroids
  Baseline11 (5.0)6 (5.5)5 (4.6)
  12 mo7 (3.2)3 (2.8)4 (3.7)
 CRP-lowering agentsc
  Baseline11 (5.0)6 (5.5)5 (4.6)
  12 mo6 (2.8)1 (0.9)5 (4.6)
  • aDietary data (FFQs) available for all participants at baseline (N = 218) but values derived from FFQ were truncated at <600 kcal and >4,000 kcal.

  • bOnly one participant was using both corticosteroid and CRP lowering agent medication simultaneously at baseline. No participant used both medication types simultaneously at 12 months.

  • cStatins, NSAIDs, ACE inhibitors.