MedicalResearch.com Interview with:
Tomás Ahern MB, BCh, BAO
St Columcille’s Hospital and St Vincent’s University Hospital
MedicalResearch.com: What are the main findings of the study?
Answer: More than 40% of severely obese people, who make up 6.5% of American adults, are at risk of vitamin D deficiency.
Severely obese people with low vitamin D levels are less active and have worse physical function than those with healthy vitamin D levels. Other investigators have found that poor physical function predicts premature death – whether this is the case in people with severe obesity remains to be determined.
MedicalResearch.com: Were any of the findings unexpected?
Answer: Yes. Other studies, of people without severe obesity, have shown that people with low vitamin D levels have higher blood sugar levels and are more likely to have diabetes. We did not find such a relationship in this study of people with severe obesity.
MedicalResearch.com: What should clinicians and patients take away from your report?
Answer: Determining serum 25-hydroxyvitamin D levels in severely obese people is appropriate because low levels are common and associated with poor physical activity and poor physical function.
The finding of a low 25-hydroxyvitamin D level should be a portal to interventions that improve physical function and should lead to consideration of vitamin D supplementation. Vitamin D supplementation can take the form of spending more time outdoors or chewing calcium and vitamin D tablets daily.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Dr. Ahern: We feel that this study generates the imperative to determine the effects of vitamin D supplementation in severely obese people at risk of vitamin D deficiency. We feel it likely that vitamin D supplementation in this group will result in improvement in physical function and possibly improvement in other markers of increased mortality.
T. Ahern, A. Khattak, E. O’Malley, C. Dunlevy, M. Kilbane, C. Woods, M. J. McKenna, D. O’Shea. Association Between Vitamin D Status and Physical Function in the Severely Obese. The Journal of Clinical Endocrinology & Metabolism, 2014; jc.2014-1704 DOI: 10.1210/jc.2014-1704