Associations of Weight-Adjusted Body Fat and Fat Distribution with Bone Mineral Density in Chinese Children Aged 6–10 Years

Abstract

Although obesity is considered osteoprotective, the effects of body fat and fat distribution on bone tissue after adjusting for the effects of body weight remain uncertain. This study evaluated the relationships between fat mass, fat distribution, and bone mineral status beyond its weight-bearing effect. We recruited 466 children aged 6-10 years in China. Dual-energy X-ray absorptiometry was used to determine the bone mineral density (BMD) and bone mineral content (BMC) in the total body and total body less head (TBLH), as well as the fat mass (FM) and percentage fat mass (%FM) of the total and segmental body. Weight-adjusted measures of FM and %FM were derived using the residual method. After adjusting for the effects of covariates, we observed statistically significant, dose-dependent negative relationships between the TBLH·BMD/BMC and various weight-adjusted measures of body fat (p for trend: <0.001-0.038). For each standard deviation increment in the weight-adjusted total body, TBLH, trunk and limbs, the size-adjusted BMC decreased approximately 9. 44, 9.28, 8.13, and 6.65 g in boys, respectively, and by approximately 13.74, 13.71, 7.84, and 12.95 g in girls, respectively. Significant inverse associations between FM accumulation in the total body and most body parts with the BMD/BMC were observed in both boys and girls after adjusting for weight and potential confounders.

Analysis of the Association between Fat Mass Distribution and Bone Mass in Chinese Male Adolescents at Different Stages of Puberty

“…Fat tissue at the trunk region had a stronger negative relationship with the studied bone parameter than did the other studied fat tissue-related variables. These findings are consistent with previous studies in children and adolescents [ 13 , 16 , 44 , 45 ]. Recently, Rokoff et al, in 876 children aged 6–10 years, also found that the inverse association between fat tissue and bone mass was driven by truncal rather than non-truncal (i.e., extremity) fat deposition [ 16 ].…”

“…Moreover, the results of those studies are inconsistent. Some studies have reported a positive association between total body FM and BMD or bone mineral content, whereas others have reported a negative or null association [ 12 , 13 , 14 , 15 , 16 , 17 ]. This disparity among studies could be due to the complex influence of FM in various parts of the body on bone health.…”

Association of Body Compositions and Bone Mineral Density in Chinese Children and Adolescents: Compositional Data Analysis

“…In addition, mechanical loading increases bone formation, while weight-bearing exercise improves bone mineral stress [30]. In other words, a higher FFM represents more muscle mass, meaning bones are loaded through muscle action (functional strain), leading to higher BMD [12]. This effect is more significant among boys because boys have far more FFM than girls.…”

“…Traditionally, obesity is considered osteoprotective because excess adipose tissue has a weight-bearing effect on bones [9,10]. But after adjusting the body weight, some studies found a negative or null association between obesity and BMD [11,12]. Body fat distribution may also impact BMD.…”

Ventricular Dysfunction in Obese and Nonobese Rats with Metabolic Syndrome

“…Moreover, HRV is used to assess heart's health status at the prognosis, diagnosis of diabetes mellitus, hypertension, MetS, and obesity [19][20][21]. The relationship between lethal ventricular arrhythmias, cardiomyopathies, and LV dysfunction (associated with dyslipidemias and visceral fat) has been poorly identified and discussed in current literature [22,23].…”