Table 1 General characteristics of the study population across categories of serum vitamin D
Variable | Categories of serum vitamin D | P-value†| ||
|---|---|---|---|---|
Deficient (< 10 ng/ml) | Insufficient (10–20 ng/ml) | Sufficient (> 20 ng/ml) | ||
N | 67 | 119 | 164 | Â |
Demographic information | ||||
 Age (year) | 32.57 ± 0.98 | 35.85 ± 0.83 | 34.89 ± 0.53 | 0.025 |
 Weight (kg) | 81.59 ± 1.57 | 82.29 ± 1.14 | 84.49 ± 1.17 | 0.240 |
 Height (cm) | 174.75 ± 0.94 | 176.96 ± 0.65 | 176.90 ± 0.60 | 0.104 |
 BMI (kg/m2) | 26.68 ± 0.42 | 26.25 ± 0.30 | 26.98 ± 0.32 | 0.272 |
 Serum vitamin D (ng/mL) | 7.20 ± 0.21 | 14.78 ± 0.28 | 29.37 ± 0.51 | < 0.001 |
 University education | 36 (53.7) | 61 (51.3) | 80 (48.8) | 0.480 |
 Employee | 26 (38.8) | 44 (37.0) | 52 (31.7) | 0.149 |
 Current smoker | 28 (41.8) | 48 (40.3) | 65 (39.6) | 0.767 |
 Having varicocele | 23 (34.3) | 57 (47.9) | 70 (42.7) | 0.443 |
Semen parameters | ||||
 Semen volume (mL) | 3.51 ± 0.27 | 3.51 ± 0.13 | 4.18 ± 0.17 | 0.009 |
 Sperm count (×106/mL) | 36.44 ± 4.75 | 43.77 ± 3.08 | 48.28 ± 2.72 | 0.068 |
 Sperm total motility (%) | 24.96 ± 2.93 | 38.36 ± 1.82 | 43.28 ± 1.64 | < 0.001 |
 Normal morphology (%) | 5.54 ± 0.47 | 6.76 ± 0.28 | 7.77 ± 0.22 | < 0.001 |
 Azoospermia | ||||
  Yes | 39 (58.2) | 57 (47.9) | 72 (43.9) | 0.058 |
  No | 28 (41.8) | 62 (52.1) | 92 (56.1) | |
Dietary intake | ||||
 Total energy (kcal/d) | 1757.32 ± 72.78 | 1684.90 ± 47.97 | 1695.50 ± 40.47 | 0.652 |
 Carbohydrate (g/d) | 246.19 ± 3.64 | 243.99 ± 2.56 | 249.66 ± 2.48 | 0.286 |
 Protein (g/d) | 61.89 ± 1.44 | 61.62 ± 1.07 | 62.98 ± 0.90 | 0.597 |
 Total fat (g/d) | 56.60 ± 1.58 | 57.82 ± 1.05 | 54.85 ± 1.01 | 0.139 |
 Total fiber (g/d) | 17.55 ± 0.74 | 17.95 ± 0.53 | 18.31 ± 0.46 | 0.665 |