Can vitamin D (Vit D) increase liver enzymes?

Can Vitamin D Increase Liver Enzymes?

Vitamin D supplementation does not typically increase liver enzymes in healthy individuals, but may actually improve liver function markers in those with abnormal liver function tests. 1

Vitamin D and Liver Function: The Evidence

Effects on Liver Enzymes

• In a study of 988 adolescents with abnormal liver function tests, high-dose vitamin D supplementation (50,000 IU cholecalciferol) was associated with significant reductions in AST, ALT, direct bilirubin, total bilirubin, LDH, and gamma-GT 1
• No significant changes in liver function tests were observed in individuals with normal baseline values 1
• In vitamin D-deficient overweight or obese adults without liver disease, vitamin D supplementation showed no effect on liver enzymes 2

Prevalence of Vitamin D Deficiency in Liver Disease

• Vitamin D deficiency is extremely common in patients with chronic liver disease, with 64-92% having levels below 20 ng/ml 3
• The deficiency is particularly pronounced in patients with cholestatic conditions and correlates with disease severity and Child-Pugh score 4

Clinical Recommendations

Monitoring and Assessment

• The American College of Gastroenterology recommends measuring 25-hydroxyvitamin D levels in all patients with chronic liver disease, especially those with:
  • Advanced disease
  • Cholestatic disorders
  • Non-alcoholic fatty liver disease 3

Supplementation Guidelines

• For patients with chronic liver disease and vitamin D deficiency:
  • Target serum vitamin D levels above 30 ng/ml 3
  • Recommended supplementation: 800 IU of vitamin D3 daily along with 1 g of calcium 4
  • Consider calcifediol (25-hydroxyvitamin D) as it doesn't require hepatic hydroxylation 3

Special Considerations

• In patients with chronic liver disease:
  • Monitor calcium levels in those at risk of hypercalcemia 3
  • Consider vitamin K supplementation in patients with jaundice or cholestatic disease 3
  • For alcoholic cirrhosis patients, thiamine (B1) supplementation should also be considered due to risk of Wernicke's encephalopathy 3

Potential Benefits Beyond Bone Health

• Vitamin D levels correlate with treatment response in:

  • Hepatitis C virus infection
  • Non-alcoholic fatty liver disease
  • Hepatocellular carcinoma development 4

• In non-diabetic patients with biopsy-proven NASH, high-dose vitamin E (800 IU/day) can improve liver histology, but safety should be considered for long-term administration 4

Conclusion

Current evidence suggests that vitamin D supplementation does not increase liver enzymes in healthy individuals. In fact, in those with abnormal liver function tests, supplementation may actually improve liver enzyme profiles 1. Given the high prevalence of vitamin D deficiency in liver disease patients, appropriate supplementation is recommended with monitoring of serum levels to achieve optimal concentrations above 30 ng/ml 3.