Effect of Vitamin D Supplementation on Free and Total Vitamin D

A Comparison of Asians and Caucasians

Jaya Sujatha Gopal-Kothandapani; Lucy Faith Evans; Jennifer S. Walsh; Fatma Gossiel; Alan S. Rigby; Richard Eastell; Nick J. Bishop


Clin Endocrinol. 2019;90(1):222-231. 

In This Article

Strengths and Limitations

Ours is the first interventional study reported so far, studying the effects of single dose of vitamin D3 on serum total 25OHD, DBP and free 25OHD concentration in both Asians and Caucasians. The main limitation of our study is the small sample size; hence, we had an insufficient statistical power to demonstrate the influence of skin types or DBP genotypes on serum 25OHD (total and free) with or without vitamin D3 supplementation. We conducted the study exclusively in young healthy males; hence, our study findings may not be applicable to conditions associated with variation in DBP levels such as gender, pregnancy, liver disease and infections, and may not necessarily be applicable across all ages. We also included no functional outcome measures.