In the USA, minority populations are growing rapidly. The expected population increase from 2010 to 2015 is 37% for Asians and 20% for Black/African Americans (AA) compared to only 13% for White/Caucasians (C). It is well known that endocrine profiles may vary in these ethnic groups, and this may be associated with adipose depots that differ from Cs. For example, AAs have higher rates of obesity than Cs, and metabolic syndrome is more prevalent in South Asians (SAs) as compared to other ethnic groups. While bone mineral density (BMD) in SAs is similar to Cs, fracture risk begins at an earlier age, and it is unclear if this is related to their lower muscle mass, higher visceral adipose tissue or altered an endocrine profile. AAs have higher muscle mass, BMD and lower fracture risk, compared to C. There are a rising number of fragility fractures in all ethnicities, and more recently, it has been shown that higher BMD in the obese is not protective. Weight loss is recommended to reduce risks associated with obesity and metabolic syndrome, but there are also changes in BMD and geometry and increased fracture risk. Previous weight loss studies have shown that postmenopausal women are particularly vulnerable to BMD loss, yet these studies reflect the response in C women. Weight loss also differentially attenuates BMD and skeletal muscle mass at different anatomical sites and these same sites show variation in fracture risk by ethnicity. Since visceral adiposity is associated with compromised BMD, this too may affect bone differently across ethnic groups. Moreover, the variations in hormones and cytokines among ethnic groups may explain a differential bone response to wt change in these populations. In addition, Ca absorption is compromised during caloric restriction, and therefore it is important to determine if it is a risk factor for weight loss induced bone loss across ethnicities. The central hypothesis is that there will be BMD loss in all ethnic groups due to wt loss that will be partially explained by a reduction in Ca absorption, whereas site specific BMD loss will differ between ethnic groups and be related to the regional changes in muscle mass. In the proposed studies, we will study 3 ethnic groups (SA, AA and C) of postmenopausal overweight/obese women before and after weight loss to: 1) determine the effect on BMD, bone geometry and strength;2) determine how BMD changes relate to changes in total and regional muscle mass and fat depots;and 3) examine if Ca absorption contributes to BMD changes with weight loss. Understanding ethnic-specific responses of bone and soft tissue to weight loss is novel and important due the unique metabolic profiles and disease risks in these ethnic groups. The ultimate goal is to develop and encourage healthy weight control strategies that are tailored to address ethnic diversity in the prevention of obesity and osteoporosis.
Obesity is a national health problem and Western diets are low in vitamin D with excess fat intake. Weight loss improves glucose homeostasis, but results in bone loss and increases fracture risk. Understanding how vitamin D and fatty acids affect calcium metabolism, bone and non-skeletal outcomes during caloric restriction is a goal in this study. We aim to make rational dietary recommendations to prevent osteoporosis and diabetes in high risk populations.
|Wang, Yang; Dellatore, Peter; Douard, Veronique et al. (2016) High fat diet enriched with saturated, but not monounsaturated fatty acids adversely affects femur, and both diets increase calcium absorption in older female mice. Nutr Res 36:742-50|
|Rosanoff, Andrea; Dai, Qi; Shapses, Sue A (2016) Essential Nutrient Interactions: Does Low or Suboptimal Magnesium Status Interact with Vitamin D and/or Calcium Status? Adv Nutr 7:25-43|
|Chang, B; Schlussel, Y; Sukumar, D et al. (2015) Influence of vitamin D and estrogen receptor gene polymorphisms on calcium absorption: BsmI predicts a greater decrease during energy restriction. Bone 81:138-44|
|Sukumar, D; Shapses, S A; Schneider, S H (2015) Vitamin D supplementation during short-term caloric restriction in healthy overweight/obese older women: Effect on glycemic indices and serum osteocalcin levels. Mol Cell Endocrinol 410:73-7|
|Pop, L Claudia; Sukumar, Deeptha; Tomaino, Katherine et al. (2015) Moderate weight loss in obese and overweight men preserves bone quality. Am J Clin Nutr 101:659-67|
|Pop, L Claudia; Shapses, Sue A; Chang, Brian et al. (2015) VITAMIN D-BINDING PROTEIN IN HEALTHY PRE- AND POSTMENOPAUSAL WOMEN: RELATIONSHIP WITH ESTRADIOL CONCENTRATIONS. Endocr Pract 21:936-42|
|Shapses, Sue (2015) The predictive value of serum 25-hydroxyvitamin D and dietary intake during adolescence: timing matters. Am J Clin Nutr 102:985-6|
|Von Thun, Nancy L; Sukumar, Deeptha; Heymsfield, Steven B et al. (2014) Does bone loss begin after weight loss ends? Results 2 years after weight loss or regain in postmenopausal women. Menopause 21:501-8|
|Jacobs, Thomas P; Kaufman, Martin; Jones, Glenville et al. (2014) A lifetime of hypercalcemia and hypercalciuria, finally explained. J Clin Endocrinol Metab 99:708-12|
|Shapses, Sue A; Lee, Esther J; Sukumar, Deeptha et al. (2013) The effect of obesity on the relationship between serum parathyroid hormone and 25-hydroxyvitamin D in women. J Clin Endocrinol Metab 98:E886-90|
Showing the most recent 10 out of 21 publications