The link between obesity and low circulating 25-hydroxyvitamin D concentrations: considerations and implications

Abstract

Obesity and vitamin D deficiency have both been recognized as major public health issues worldwide, and there is growing evidence that they are related, although the cause-effect relationship remains unclear. Could obesity be contributing to low circulating 25-hydroxyvitamin D concentrations? Alternatively, could low vitamin D status predispose to obesity? In this review, the relationship between low circulating 25-hydroxyvitamin D and obesity, and possible underlying reasons from both perspectives, is presented. One potential mechanism by which obesity could contribute to low serum 25-hydroxyvitamin D is adipose sequestration of vitamin D. On the other hand, adipose tissue has both the vitamin D receptor and the ability to synthesize 1,25-dihydroxyvitamin D, and there is evidence that vitamin D may regulate adipose tissue mass, differentiation and metabolism in ways that might contribute to obesity. Of particular interest, vitamin D deficiency is common both before and after bariatric surgery, and is often difficult to treat, particularly with the more malabsorptive procedures. Additional research is needed to elucidate the complex and multifaceted factors underlying the association between low circulating 25-hydroxyvitamin D and obesity, and to identify optimal treatment approaches in obese individuals and in bariatric surgical patients both before and after surgery.

Lipid Accumulation Product and 25-OH-Vitamin D Deficiency in Type 2 Diabetes

“…The present study confirms the well-known association of obesity with vitamin D deficiency [21]. In addition, lower levels of vitamin D were observed in patients with higher WC and with MetS, again confirming the previous observations [22].…”

Contribution of vitamin D insufficiency to the pathogenesis of multiple sclerosis

“…Moreover, exposure to the sun is often avoided due to dermatological concerns and people with dark skins and older people synthesize vitamin D less easily than people with light skins and the young [Vieth, 1999;Armas et al 2007;Binkley et al 2007]. Lastly, in people who are overweight, (liposoluble) vitamin D is partly sequestered in adipocytes, which may contribute to a worsening of insufficiency [Earthman et al 2012].…”

Bariatric surgery and bone disease: from clinical perspective to molecular insights

“…Obese individuals in general often have abnormally low 25(OH)-vitamin D levels, a phenomenon that is thought to occur as a result of sequestration of vitamin D in the excess adipose tissue or from inadequate sunlight exposure related to both a more sedentary lifestyle and a tendency to 'cover up' due to modesty. 46 Patients who undergo bariatric surgery, frequently develop abnormalities of both calcium homeostasis and bone metabolism with the magnitude of the changes being directly proportional to the amount of weight lost. 47 Abnormalities of vitamin D and parathyroid hormone are particularly variable, depending on the type of procedure performed.…”