The vitamin D field is in a state of uncertainty, with clinicians recommending high doses with the belief that it will prevent a wide range of diseases, but these recommnedations are almost entirely based on observational studies. Patients with obesity are often vitamin D deficient, and lose bone with weight reduction (nearly ½ of the US population is dieting at any given time), but almost no studies have addressed whethervitamin D supplementation may benefit this population and attenuate non-skeletal outcomes during caloric restriction. There are a large number of ongoing trials, but none focus on obesity or weight loss. Obesity reduces serum levels of 25 hydroxy-vitamin D (25OHD) and increases parathyroid hormone (PTH) and markers of chronic low inflammation, which can contribute to poor bone quality, insulin resistance, and poor cognition. Evidence shows that both weight reduction and vitamin D supplementation will positively influence outcomes related to insulin resistance and cognitive abilities. The interaction between dietary vitamin D and its endocrine actions on non-skeletal effects (including cognition and diabetes) will also affect bone quality and risk of falling and ultimately affect fracture risk.. In another project, we will examine how dietary fat affects calcium and bone metabolism in a mature murine model. While very high intakes of dietary fat during growth reduce calcium absorption and bone mineral density, little is known about how dietary fat affects calcium absorption and bone during normal caloric intake. We hypothesize that adequate dietary fat is important for absorption and bone health under certain conditions. It is expected that this research will provide insight into important mechanisms regulating the inter-relationship between adipose tissue and vitamin D metabolism, and dietary fat that can influence and improve nutritional recommendations during dieting.
|Effective start/end date||1/10/14 → 9/30/18|
- National Institute of Food and Agriculture (National Institute of Food and Agriculture (NIFA))