Higher Total Body Bone Mineral Density Research Articles

Daily Intake of a Functional Synbiotic Yogurt Increases Calcium Absorption in Young Adult Women

Foods containing both prebiotics and probiotics (synbiotics) might enhance calcium bioavailability. We investigated the acute effect in young adult women on calcium absorption of consuming (185mL) a synbiotic yogurt (SYN) containing inulin (4 g)andLactobacillus rhamnosus GG (>1×107 CFU/mL) compared with a control yogurt (CON). Adult normal-weight women (25.0±3.5y, n=30) participated in a 3-wk crossover study testing daily consumption of SYN compared with CON. Habitual dietary intake, bone mineral density (BMD), calcium biomarkers, and serum 25-hydroxyvitamin D were measured at baseline. Calcium absorption was tested after each phase of the study using a 42Ca oral tracer. Cumulative tracer recovery was measured in 0-4-h, 0-24-h, and0-36-hurine pools collected postdosing. The SYN/CON tracer ratio from the timed urine pools was the primary outcome. A beneficial response to SYN was defined as 0-36-hSYN/CON tracer ratio>1. Net 42Ca recovered increased over time in each of the SYN and CON urine pools postdosing (Friedman, P<0.001), with a trend for higher 42Ca recovery in the 0-36-hurine pool postdosing in the SYN (1.14%) compared with the CON (0.90%) study (Wilcoxon, P=0.07). For CON, the majority of total tracer was recovered in the 0-24-hpool (86%), whereas for SYN only 50% of total tracer was recovered in the 0-24-hpool (Friedman, P=0.001). The SYN/CON tracer ratio in the 0-36-hpool (1.24) was >1 (Wilcoxon, P=0.015). About two-thirds (n=19) of women studied responded to the SYN treatment. Responders had higher vegetable intake (P=0.03), tended to have higher potassium and calcium intakes (P≤0.08), and had higher total body BMD (P=0.09), than nonresponders. Short-term daily consumption of a synbiotic yogurt enhanced calcium absorption relative to a control yogurt in adult women. Given the observed time delays in tracer recovery, enhancement of calcium absorption likely occurred in the large intestine.The study was registered at clinicaltrials.gov (study registration ID: NCT03420716).

Bone mineral density in high-level endurance runners: Part B\u2014genotype-dependent characteristics

PurposeInter-individual variability in bone mineral density (BMD) exists within and between endurance runners and non-athletes, probably in part due to differing genetic profiles. Certainty is lacking, however, regarding which genetic variants may contribute to BMD in endurance runners and if specific genotypes are sensitive to environmental factors, such as mechanical loading via training.MethodTen single-nucleotide polymorphisms (SNPs) were identified from previous genome-wide and/or candidate gene association studies that have a functional effect on bone physiology. The aims of this study were to investigate (1) associations between genotype at those 10 SNPs and bone phenotypes in high-level endurance runners, and (2) interactions between genotype and athlete status on bone phenotypes.ResultsFemale runners with P2RX7 rs3751143 AA genotype had 4% higher total-body BMD and 5% higher leg BMD than AC + CC genotypes. Male runners with WNT16 rs3801387 AA genotype had 14% lower lumbar spine BMD than AA genotype non-athletes, whilst AG + GG genotype runners also had 5% higher leg BMD than AG + GG genotype non-athletes.ConclusionWe report novel associations between P2RX7 rs3751143 genotype and BMD in female runners, whilst differences in BMD between male runners and non-athletes with the same WNT16 rs3801387 genotype existed, highlighting a potential genetic interaction with factors common in endurance runners, such as high levels of mechanical loading. These findings contribute to our knowledge of the genetic associations with BMD and improve our understanding of why some runners have lower BMD than others.

Disentangling the body weight-bone mineral density association among breast cancer survivors: an examination of the independent roles of lean mass and fat mass

BackgroundBone mineral density (BMD) and lean mass (LM) may both decrease in breast cancer survivors, thereby increasing risk of falls and fractures. Research is needed to determine whether lean mass (LM) and fat mass (FM) independently relate to BMD in this patient group.MethodsThe Health, Eating, Activity, and Lifestyle Study participants included 599 women, ages 29–87 years, diagnosed from 1995–1999 with stage 0-IIIA breast cancer, who underwent dual-energy X-ray absorptiometry scans approximately 6-months postdiagnosis. We calculated adjusted geometric means of total body BMD within quartiles (Q) of LM and FM. We also stratified LM-BMD associations by a fat mass index threshold that tracks with obesity (lower body fat: ≤12.9 kg/m2; higher body fat: >12.9 kg/m2) and stratified FM-BMD associations by appendicular lean mass index level corresponding with sarcopenia (non-sarcopenic: ≥ 5.45 kg/m2 and sarcopenic: < 5.45 kg/m2).ResultsHigher LM (Q4 vs. Q1) was associated with higher total body BMD overall (1.12 g/cm2 vs. 1.07 g/cm2, p-trend < 0.0001), and among survivors with lower body fat (1.13 g/cm2 vs. 1.07 g/cm2, p-trend < 0.0001) and higher body fat (1.15 g/cm2 vs. 1.08 g/cm2, p-trend = 0.004). Higher FM (Q4 vs. Q1) was associated with higher total body BMD overall (1.12 g/cm2 vs. 1.07 g/cm2, p-trend < 0.0001) and among non-sarcopenic survivors (1.15 g/cm2 vs. 1.08 g/cm2, p < 0.0001), but the association was not significant among sarcopenic survivors (1.09 g/cm2 vs. 1.04 g/cm2, p-trend = 0.18).ConclusionAmong breast cancer survivors, higher LM and FM were independently related to higher total body BMD. Future exercise interventions to prevent bone loss among survivors should consider the potential relevance of increasing and preserving LM.

Young Women with Cold-Activated Brown Adipose Tissue Have Higher Bone Mineral Density and Lower Pref-1 than Women without Brown Adipose Tissue: A Study in Women with Anorexia Nervosa, Women Recovered from Anorexia Nervosa, and Normal-Weight Women

Anorexia nervosa (AN) is associated with depletion of body fat, loss of bone mineral density (BMD), and impaired thermogenesis. Brown adipose tissue (BAT) is lower in obese individuals and decreases during aging. Recent studies have suggested a link between BAT and bone metabolism. Our objective was to investigate the presence and quantity of BAT in patients with AN, recovered AN (AN-R), and normal-weight controls and to study the relationship between BAT and BMD and body composition and investigate hormonal predictors of BAT. This was a cross-sectional study at a clinical research center. Patients included 15 women: five with AN (mean age 30 ± 6.3 yr), five AN-R, and five healthy nonobese controls of comparable age. Cold-activated BAT was determined by fluorodeoxyglucose-positron emission tomography/computed tomography. BMD of total-body, spine, and hip, fat and lean mass was determined by dual-energy x-ray absorptiometry. Single-slice magnetic resonance imaging at L4 was done for abdominal fat compartments, and preadipocyte factor-1 (Pref-1), T₃, and T₄ were measured. Within the AN group, one of five; in the AN-R group, two of five; and in the healthy nonobese control group, four of five subjects were BAT positive. Subjects were divided into groups based on the presence (n = 7) or absence (n = 8) of BAT. Both groups were of comparable age and body mass index. Women with BAT had higher total-body BMD, higher T₃, and lower Pref-1 compared with women without BAT. There was a positive correlation between BAT and BMD that remained significant after controlling for disease status and body mass index. Young women with AN have low cold-activated BAT, which may be due to impaired BAT thermogenesis. Young women with BAT have higher BMD and lower Pref-1 compared with women without BAT, suggesting that BAT may be involved in the regulation of stem cell differentiation into the bone lineage at the expense of adipogenesis.

The positive effect of dietary vitamin D intake on bone mineral density in men is modulated by the polyadenosine repeat polymorphism of the vitamin D receptor

Introduction:Few studies have considered the dietary influence of vitamin D intake on bone mineral density (BMD). Numerous studies have examined the association between VDR polymorphism and BMD, but no previous study has examined the joint influence of dietary vitamin D intake and VDR polymorphism on BMD. Methods:We therefore conducted a study in 230 men aged 41–76 years of age. BMD was measured with DXA. A second bone scan was performed on average 2.7 years after the first investigation. Dietary habits were assessed by 14 dietary 24-h recall interviews. The polyadenosine (A) VDR genotypes were determined. Results:Dietary vitamin D intake was associated with BMD at all sites, also after multivariate adjustment. Those in the highest quintile of intake had 9% higher femoral neck BMD (p=0.004), 6% higher BMD at the lumbar spine (p=0.06) and 5% higher total body BMD (p=0.003) compared to men in the lowest quintile of dietary vitamin D intake. However, the positive association between vitamin D intake and BMD was especially apparent among those with the L/L polyadenosine (A) VDR genotype explaining between 10 and 15% of the variability in BMD depending on site (p<0.004). There was furthermore a trend, in the lumbar spine, of less reduction in BMD with increasing vitamin D intake (p=0.07) but not at the other sites. Calcium intake conferred no association with BMD. Conclusions:Our results indicate that the extent of positive association between dietary vitamin D intake and BMD in men is dependent on VDR polymorphism, a novel conceivable important gene–environmental interaction.

Multiple endocrine neoplasia type 1 polymorphism D418D is associated with sporadic primary hyperparathyroidism

Background. Sporadic primary hyperparathyroidism (pHPT) occurs separately and in several hereditary disorders including multiple endocrine neoplasia type 1. Irradiation to the neck, female gender, and age are well-identified risk factors that predispose to pHPT. The multiple endocrine neoplasia type 1 gene is the most commonly deranged gene in parathyroid adenomas and contains several polymorphisms including D418D with a prevalence of roughly 50%. Methods. We genotyped 162 pHPT patients and control participants to evaluate if the D418D polymorphism is related to development of pHPT. One hundred fourteen of the pHPT patients and control participants were recruited from a health screening and were subjected to measurement of bone mineral density (BMD) at the lumbar spine, femoral neck, and total body. Results. The prevalence of each genotype (ie, MM, Mm, and mm) was for all pHPT patients: 62%, 29%, and 9%; and for all control participants: 32%, 43%, and 25% (P <.0004). For the screening-detected pHPT patients and control participants, the genotype distribution for MM, Mm, and mm was 60%, 30%, and 10%; and 31%, 44%, and 25%, respectively (P =.009). In the screening-recruited control participants, but not in pHPT patients, the MM genotype was also associated with higher total body BMD (P =.01) and BMD at the femoral neck (P =.02), whereas it failed to be significant for BMD at the lumbar spine (P =.08). Conclusions. We report that the MM genotype was overrepresented in pHPT patients compared with control participants, suggesting a novel marker for pHPT. Furthermore, the MM genotype was associated with higher BMD at the femoral neck and in the total body in the screening-recruited control participants. (Surgery 2002;132:450-5.)

Multiple endocrine neoplasia type 1 polymorphism D418D is associated with sporadic primary hyperparathyroidism

Background. Sporadic primary hyperparathyroidism (pHPT) occurs separately and in several hereditary disorders including multiple endocrine neoplasia type 1. Irradiation to the neck, female gender, and age are well-identified risk factors that predispose to pHPT. The multiple endocrine neoplasia type 1 gene is the most commonly deranged gene in parathyroid adenomas and contains several polymorphisms including D418D with a prevalence of roughly 50%. Methods. We genotyped 162 pHPT patients and control participants to evaluate if the D418D polymorphism is related to development of pHPT. One hundred fourteen of the pHPT patients and control participants were recruited from a health screening and were subjected to measurement of bone mineral density (BMD) at the lumbar spine, femoral neck, and total body. Results. The prevalence of each genotype (ie, MM, Mm, and mm) was for all pHPT patients: 62%, 29%, and 9%; and for all control participants: 32%, 43%, and 25% (P <.0004). For the screening-detected pHPT patients and control participants, the genotype distribution for MM, Mm, and mm was 60%, 30%, and 10%; and 31%, 44%, and 25%, respectively (P =.009). In the screening-recruited control participants, but not in pHPT patients, the MM genotype was also associated with higher total body BMD (P =.01) and BMD at the femoral neck (P =.02), whereas it failed to be significant for BMD at the lumbar spine (P =.08). Conclusions. We report that the MM genotype was overrepresented in pHPT patients compared with control participants, suggesting a novel marker for pHPT. Furthermore, the MM genotype was associated with higher BMD at the femoral neck and in the total body in the screening-recruited control participants. (Surgery 2002;132:450-5.)

Normal bone mass in bulimic women.

The aim of this study was to examine the relationship among exercise, menstrual function, and bone mineral density (BMD) in different groups of age-matched patients with eating disorders. Dieting and eating disorder history, physical activity history, and menstrual history were assessed by clinical interview in 43 bulimic and 13 anorectic young women as well as in 17 healthy control subjects (18-29 yr). BMD was assessed by dual x-ray absorptiometry. All the anorectics but only 30% of the bulimics exercised regularly from the onset of their eating disorder (P < 0.01), mainly using aerobic dancing and running. All of the anorectics had been amenorrheic since the start of their symptoms, and 68% of the bulimics had a history of menstrual dysfunction. Within the exercise subgroups of bulimic patients, there was no significant relationship between BMD and current or previous menstrual function. Anorectic patients had lower BMD than bulimics and controls in all skeletal regions studied (P < 0.01). Bulimic patients who had exercised regularly during their illness had higher total body BMD than bulimics classified as sedentary (P < 0.01). Bulimics who had exercised regularly or intermittently since the onset of their eating disorder had higher BMD than sedentary bulimics in the lumbar vertebrae, femoral neck, and legs (P < 0.05). It appears that weight-bearing exercise can prevent or attenuate bone loss at specific skeletal sites in normal weight bulimic patients, but not in anorectics.

Bone mineral density in elite 7- to 9-yr-old female gymnasts and swimmers.

It is has been suggested that physical activity may increase bone mineral density (BMD) in children, thereby preventing development of osteoporosis later in life. We studied 14 gymnasts, 14 swimmers, and 17 controls to investigate whether participation in different types of sports among girls 7-9 yr of age is associated with higher total body BMD. Gymnasts were lighter than both swimmers and controls (P = 0.001), and a larger percent of gymnasts compared with swimmers and controls were below the 25th percentile for height and weight. Fat mass, percent body fat, and lean mass were less in gymnasts compared with swimmers and controls (all P < or = 0.05). The relationship between total body BMD and body weight differed among the three groups (interaction term of weight and sport, P < 0.001); the increase in BMD per unit increase in body weight was more among gymnasts than among swimmers and controls. These results indicate that high impact bone loading activities may lead to increased bone density among young girls.