Optimal Serum 25(OH)D Levels and Vitamin D Intake in Korean Postmenopausal Women
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Participants
2.2. General Characteristics, Lifestyle, and Outdoor Time
2.3. Dietary Assessment
2.4. Anthropometry, Biochemical Indices, and Bone Mineral Density
2.5. Statistical Analysis
3. Results
3.1. General Characteristics and Lifestyle of the Participants
3.2. Body Mass Index, Biochemical Indices, and Bone Mineral Density by Season
3.3. Correlation Coefficient of Body Mass Index, Biochemical Indices, and Bone Mineral Density
3.4. Nutrient Intake
3.5. Serum 25(OH)D Level According to Vitamin D Supplementation
3.6. Exponential Decay for Optimal Serum 25(OH)D to Suppress iPTH Elevation
3.7. Relationship between Bone Mineral Density and Serum 25(OH)D Levels
3.8. L-Spine Bone Mineral Density According to Calcium and Vitamin D Intake
3.9. Multivariate Linear Regression Analyzing the Factors Influencing the Serum 25(OH)D Level by Season
3.10. ROC Analysis for Optimal Vitamin D Intake at Serum 25(OH)D ≥20 and ≥18.9 ng/mL
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Variables | Mean ± S.E or N (%) | |
---|---|---|
N | 96 (100.0) | |
Age (years) | 57.08 ± 0.55 | |
YSM (years) | 7.27 ± 0.57 | |
Height (cm) | 158.2 ± 0.51 | |
Weight (kg) | 58.42 ± 0.85 | |
Number of ways to avoid sun exposure | 0 | 9 (9.4) |
1 | 9 (9.4) | |
2 | 20 (20.8) | |
≥3 | 58 (60.4) | |
Subtotal | 96 (100.0) | |
Alcohol consumption | Yes | 34 (35.4) |
No | 62 (64.6) | |
Subtotal | 96 (100.0) | |
IPAQ | High | 6 (6.3) |
Moderate | 73 (76.0) | |
Low | 17 (17.7) | |
Subtotal | 96 (100.0) | |
Taking vitamin D supplements | Summertime | 50 (52.1) |
Wintertime | 53 (55.2) | |
Taking calcium supplements | Summertime | 25 (26.0) |
Wintertime | 34 (35.4) | |
sun exposure time (min) | Summertime | 35.95 ± 2.59 |
Wintertime | 38.23 ± 2.91 N.S. |
Annual Average | Summertime | Wintertime | |||||||
---|---|---|---|---|---|---|---|---|---|
L-Spine 1–4 | Femoral Neck | Total Hip | L-Spine 1–4 | Femoral Neck | Total Hip | L-Spine 1–4 | Femoral Neck | Total Hip | |
BMI | 0.245 * | 0.306 ** | 0.398 *** | 0.213 * | 0.262 * | 0.379 *** | 0.255 * | 0.323 ** | 0.397 *** |
iPTH | −0.088 | −0.161 | −0.144 | −0.120 | −0.147 | −0.176 | −0.041 | −0.138 | −0.100 |
BAP | −0.174 | −0.180 | −0.196 | −0.139 | −0.143 | −0.155 | −0.198 | −0.214 * | −0.233 ** |
NTX | −0.205 * | −0.150 | −0.197 | −0.153 | −0.114 | −0.123 | −0.236 * | −0.152 | −0.230 * |
25(OH)D | −0.090 | −0.131 | −0.154 | −0.112 | −0.124 | −0.150 | −0.057 | −0.091 | −0.129 |
serumcalcium | 0.139 | −0.011 | 0.001 | 0.123 | −0.035 | −0.007 | 0.337 | 0.879 | 0.882 |
Nutrients per 1000 kcal (n = 96) | |||||
---|---|---|---|---|---|
Variables | Summertime | Wintertime | Annual Average | p-Value | |
Energy (kcal/day) | 1623.38 ± 36.54 | 1736.27 ± 49.10 | 1679.83 ± 35.64 | 0.024 | |
Carbohydrate (g/1000 kcal/day) | 135.40 ± 1.74 | 136.11 ± 1.93 | 135.75 ± 1.48 | 0.872 | |
Protein (g/1000 kcal/day) | 44.36 ± 0.68 | 43.11 ± 0.55 | 43.73 ± 0.45 | 0.135 | |
Fat (g/1000 kcal/day) | 31.41 ± 0.54 | 31.27 ± 0.66 | 31.34 ± 0.48 | 0.530 | |
Calcium total (mg/1000 kcal/day) † | 372.04 ± 13.40 | 397.98 ± 16.39 | 385.01 ± 12.50 | 0.136 | |
With supplements | 529.61 ± 22.43 | 549.89 ± 28.00 | |||
Without supplements | 316.56 ± 9.99 | 314.67 ± 9.74 | |||
p-value | <0.001 | <0.001 | |||
Vitamin D total (µg/1000 kcal/day) ‡ | 10.07 ± 1.31 | 11.51 ± 1.48 | 10.79 ± 1.07 | 0.371 | |
With supplements | 16.52 ± 2.13 | 18.79 ± 2.23 | |||
Without supplements | 3.06 ± 0.24 | 2.53 ± 0.25 | |||
p-value | <0.001 | <0.001 |
Skeletal Site | Serum 25(OH)D Level | β | 95% CI | p-Value |
---|---|---|---|---|
L-spine 1–4 | <20 ng/mL † (n = 39) | 0.004 | −0.013, 0.021 | 0.639 |
≥20 ng/mL (n = 57) | −0.002 | −0.007, 0.004 | 0.595 | |
Femoral neck | <20 ng/mL (n = 39) | 0.012 | 0.001, 0.022 | 0.038 |
≥20 ng/mL (n = 57) | −0.001 | −0.005, 0.002 | 0.449 | |
Total hip | <20 ng/mL (n = 39) | 0.013 | 0.000, 0.026 | 0.050 |
≥20 ng/mL (n = 57) | −0.001 | −0.005, 0.002 | 0.378 | |
L-spine 1–4 | <18.9 ng/mL ‡ (n = 36) | 0.006 | −0.013, 0.024 | 0.532 |
≥18.9 ng/mL (n = 60) | −0.001 | −0.006, 0.004 | 0.673 | |
Femoral neck | <18.9 ng/mL (n = 36) | 0.015 | 0.004, 0.027 | 0.010 |
≥18.9 ng/mL (n = 60) | 0.000 | −0.004, 0.003 | 0.784 | |
Total hip | <18.9 ng/mL (n = 36) | 0.018 | 0.005, 0.031 | 0.007 |
≥18.9 ng/mL (n = 60) | −0.001 | −0.004, 0.002 | 0.647 |
Seasons | Variables | β | 95% CI | p-Value |
---|---|---|---|---|
Annual average | Vitamin D intake (µg/1000 kcal) | 0.370 | 0.204, 0.536 | <0.001 |
BMI (kg/m2) | −0.928 | −1.522, −0.334 | 0.003 | |
sun exposure time (min) | 0.105 | 0.014, 0.195 | 0.024 | |
Summertime | Vitamin D intake (µg/1000 kcal) | 0.226 | 0.071, 0.381 | 0.005 |
sun exposure time (min) | 0.100 | 0.022, 0.178 | 0.013 | |
BMI (kg/m2) | −0.674 | −1.318, −0.030 | 0.040 | |
Wintertime | Vitamin D intake (µg/1000 kcal) | 0.314 | 0.182, 0.446 | <0.001 |
BMI (kg/m2) | −0.985 | −1.637, −0.334 | 0.003 |
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Shin, H.R.; Lee, Y.J.; Ly, S.Y. Optimal Serum 25(OH)D Levels and Vitamin D Intake in Korean Postmenopausal Women. Nutrients 2023, 15, 1856. https://doi.org/10.3390/nu15081856
Shin HR, Lee YJ, Ly SY. Optimal Serum 25(OH)D Levels and Vitamin D Intake in Korean Postmenopausal Women. Nutrients. 2023; 15(8):1856. https://doi.org/10.3390/nu15081856
Chicago/Turabian StyleShin, Hye Ran, Ye Jin Lee, and Sun Yung Ly. 2023. "Optimal Serum 25(OH)D Levels and Vitamin D Intake in Korean Postmenopausal Women" Nutrients 15, no. 8: 1856. https://doi.org/10.3390/nu15081856