Association of vitamin D deficiency with high cholesterol levels

Background

Recent studies have demonstrated a significant relationship between vitamin D and cholesterol levels. Cholesterol is important in the synthesis and metabolism of vitamin D. Additionally, foods rich in vitamin D also contain high cholesterol supplements. Given that sources of vitamin D and cholesterol are different, we hypothesized that there is a potential mean bias in true relationship between an individual’s vitamin D and cholesterol levels. The study therefore aimed to examine the relationship of serum cholesterol and vitamin D levels.

Methods

We utilized NHANES 2001-2006 data (n=30,954). The outcome was vitamin D deficiency defined as individuals with serum 25-hydroxyvitamin D level<12 ng/ml, while those with serum level >12 ng/ml were classified as normal. Significant differences in cholesterol levels between the two groups were determined using Chi-Square contingency test.  Generalized linear models were conducted to assess the association of vitamin D deficiency with cholesterol levels adjusting for age, sex, physical activity (proxy measure for sunlight exposure) and other serum lipid levels.

Results

Vitamin D deficiency was significantly lower in males(5.2%) than females(7.8%)(P<0.0001), and participants aged ≤18 years relative to other age categories(P<0.0001). Compared to individuals with normal vitamin D levels, deficient individuals had higher levels of Low Density Lipoprotein (LDL)(P=0.0033) and Triglycerides (P=0.0245). No significant differences were identified in total cholesterol and High Density Lipoproteins (HDL) levels.

Conclusion

Vitamin D deficiency was associated with high LDL and triglyceride levels. Study findings help establish the importance of distinguishing vitamin D and cholesterol levels as separate entities while making inferences about their relationship with chronic diseases.