The effect of vitamin D supplementation on some metabolic parameters in patients with nonalcoholic fatty liver disease: A systematic review and meta-analysis of 8 RCTs.
Study Goal
The researchers aimed to evaluate the effects of vitamin D supplementation on 25(OH)D levels, insulin resistance, fasting blood glucose, and fasting insulin levels in patients with nonalcoholic fatty liver disease (NAFLD).
Results Summary
Vitamin D supplementation significantly increased 25(OH)D levels but had no significant effect on insulin resistance, fasting blood glucose, or fasting insulin levels. The meta-analysis included eight randomized controlled trials with mixed results on metabolic outcomes.
Population
Patients with nonalcoholic fatty liver disease (NAFLD)
Effective Dosage
Not specified
Duration
Not specified
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
Vitamin D supplementation | increase | 25-hydroxyvitamin D [25(OH)D] levels | patients with nonalcoholic fatty liver disease (NAFLD) | mean difference [MD] = 2.01, 95% confidence intervals [CI]: 0.94 to 3.08, P < .05 | increased significantly | #1 |
Vitamin D supplementation | decrease | insulin resistance index (homeostasis model assessment of insulin resistance) | patients with nonalcoholic fatty liver disease (NAFLD) | MD = -0.54, 95% CI: -1.28 to 0.20, P = .16 | had a significant effect on | #2 |
Vitamin D supplementation | no change | fasting glucose | patients with nonalcoholic fatty liver disease (NAFLD) | MD = -0.59, 95% CI: -1.50 to 0.32, P = .20 | had no significant effect on | #3 |
Vitamin D supplementation | no change | fasting insulin levels (FINS) | patients with nonalcoholic fatty liver disease (NAFLD) | MD = -0.30, 95% CI: -0.77 to 0.17, P = .21 | had no significant effect on | #4 |
Vitamin D supplementation | increase | 25(OH)D levels | patients with nonalcoholic fatty liver disease | - | improves | #5 |
Vitamin D supplementation | no change | homeostasis model assessment of insulin resistance | patients with nonalcoholic fatty liver disease | - | no effect on | #6 |
Vitamin D supplementation | no change | fasting blood glucose | patients with nonalcoholic fatty liver disease | - | no effect on | #7 |
Vitamin D supplementation | no change | FINS | patients with nonalcoholic fatty liver disease | - | no effect on | #8 |
BACKGROUND: To systematically evaluate the effects of vitamin D supplementation in patients with nonalcoholic fatty liver disease (NAFLD). METHODS: National Library of Medicine, Cochrane Library, Elsevier, China National Knowledge Infrastructure, Web of Science, WANFANG databases, and Google Scholar were retrieved to collect relevant randomized controlled trials, which are published from the earliest records the time the database was created to April 2023. Meta-analysis was conducted by using Review Manager 5.4 software after evaluating in terms of inclusion and exclusion criteria. The outcome indicators include 25-hydroxyvitamin D [25(OH)D] levels, insulin resistance index (homeostasis model assessment of insulin resistance), fasting blood glucose, and fasting insulin levels (FINS). RESULTS: Eight randomized controlled trials with a total of 657 patients are included. Vitamin D supplementation increased 25(OH)D levels significantly (mean difference [MD] = 2.01, 95% confidence intervals [CI]: 0.94 to 3.08, P < .05) and vitamin D supplementation had a significant effect on insulin resistance index (MD = -0.54, 95% CI: -1.28 to 0.20, P = .16), fasting glucose (MD = -0.59, 95% CI: -1.50 to 0.32, P = .20), and FINS levels (MD = -0.30, 95% CI: -0.77 to 0.17, P = .21) had no significant effect. CONCLUSION: Vitamin D supplementation improves 25(OH)D levels in patients with nonalcoholic fatty liver disease, but there is no effect on homeostasis model assessment of insulin resistance, fasting blood glucose, or FINS.