A new study in International Journal of Biomedical Science has shown that vitamin D can be safely and effectively absorbed through the skin.
Administering substances through the skin in order to be absorbed and distributed throughout the body is known as transdermal administration. Transdermal administration is a relatively recent discovery in medicine and has been used and is currently used to administer various pharmaceutical compounds such as scopolamine (treats motion sickness), nicotine, and testosterone.
The current study used transdermal administration to address an overlooked problem with vitamin D supplementation. This is the problem in which vitamin D deficiency still occurs in people who are prescribed adequate doses of vitamin D.
There are many reasons why people may have trouble raising their levels when supplementing with vitamin D. One of the reasons is that patients who are taking multiple medications have increased stress and a harder time complying with taking all of the different medications. This is called medication burden.
The compliance of oral vitamin D and calcium supplementation is estimated to be 20-60%. The researchers of this study therefore hypothesized that topical delivery of vitamin D may be an easier and more acceptable route of delivery for vitamin D than oral methods such as pill, tablet, or liquid forms.
The study was a pilot study, meaning it was a small scale, preliminary study conducted in order to evaluate the cost-effectiveness, side effects, and feasibility of topical delivery of vitamin D so as to inform larger and better designed studies in the future.
Researchers from the University of Dammam in Saudi Arabia randomly assigned 48 healthy female medical students to a treatment group or a placebo control group and measured their vitamin D levels to get a baseline reading. The treatment group applied one gram of cream on their skin daily that contained 5000 IU of vitamin D in an aloe vera base. The control group applied one gram of just aloe vera cream on their skin daily. The women had no knowledge of which group they belonged to. After three months of topical application, their vitamin D levels were measured again.
The results were compelling:
- The average vitamin D levels in the treatment group before and after treatment were 12.05 ng/ml and 37.95 ng/ml, respectively.
- The average vitamin D levels in the control group before and after treatment were 10.4 ng/ml and 9.58 ng/ml, respectively.
- The difference in levels after treatment between the two groups was statistically significant (p= 0.001).
The researchers concluded,
“Our study shows that our formulation of vitamin D3 can safely and effectively be delivered by dermal route, reducing the incidence of non-compliance of oral route.”
Transdermal delivery of vitamin D looks to be a promising and effective method of vitamin D supplementation. However, the study is limited by its small sample size. Future studies with larger sample sizes of greater duration are needed to confirm and expand upon the safety and benefits of this form of supplementation in other populations such as in men and in those who have intestinal problems that interfere with the absorption of dietary and supplemental vitamin D.