The Effects of Lifestyle, Dietary Dairy Intake and Diabetes on Bone Density and Vertebral Deformity Prevalence: The EVOS Study

The risk of low and moderate energy fracture is related to bone mineral density (BMD). Yet it is uncertain whether the epidemiologic determinants of fracture risk are the same as for low bone density. The European Vertebral Osteoporosis Study was a population-based prevalence study of vertebral deformity in 36 age-stratified population samples aged 50–80 years. In nearly 4000 subjects (13 centers), BMD measurements were also made at the spine, femoral neck and femoral trochanter. To investigate whether effects of reported physical activity on spine deformity risk were mediated through BMD, we modeled these and other risk factor data with BMD as the dependent variate after adjusting for age, center, sex and body mass index (BMI). The significant determinants of vertebral deformity risk were also entered into logistic models of deformity risk that included BMD measurements as covariates. Both current and lifetime physical activity were positively associated with BMD. This effect was stronger with hip BMD than with spine BMD. Lifetime smoking exposure was associated with reduced BMD. Type 2 diabetes mellitus was associated with increased BMD. Weak positive associations were found between consumption of dairy products and BMD at the three measured sites and these were strengthened by an interaction with measures of physical activity in men. Physical activity in women had the largest beneficial effect in lean women and in women exposed to hormone replacement therapy. When fracture risk was modeled with BMD as a covariate, the lifestyle and dietary determinants became less strongly related to vertebral deformity risk, suggesting that BMD may have acted as an intermediary variable. However, heavy physical activity in men still increased spine deformity risk after adjusting for BMD. It is concluded that physical activity in both genders and milk consumption in young women might protect against vertebral deformities in later life through their effects on bone density. The adverse effect of smoking on BMD was confirmed. Heavy physical activity in men might increase spine deformity risk even when BMD is normal. Received: 29 June 2000 / Accepted: 5 January 2001     

Assessment of age and risk factors on bone density and bone turnover in healthy premenopausal women

The influence of age and risk factors on bone density and bone turnover was evaluated in 249 healthy premenopausal women. Risk factors were assessed by standardized questionnaires and included reproductive history and lifestyle factors (intake of calcium and vitamin D supplements, consumption of caffeine, smoking habits and physical activity). Bone mineral density (BMD) measurements were obtained in the distal forearm, the lumbar spine and the proximal femur. Bone turnover were assessed by plasma bone Gla proteins (pBGP) and fasting urinary hydroxyproline corrected for creatinine (fUHPr/Cr). Peak bone density seems to be achieved before the age of 30 years, whereafter we found no appreciable bone loss at any skeletal site. Accordingly, the levels of pBGP and fUHPr/Cr were increased before the age of 30, whereafter the values stabilized at a lower level. A dairy calcium intake above 660 mg/day significantly increased BMD in the spine and proximal femur by 3%–5%. Physical activity alone had no influence on BMD, but in combination with calcium intake an additive effect was observed. Women who had an active lifestyle (corresponding to at least 1 h of daily walking) and a dairy calcium intake above 660 mg/day had a 3%–7% increase in BMD compared with more sedentary women with a calcium intake below this limit. Vitamin D supplements, caffeine, smoking and reproductive history did not consistently influence BMD or bone turnover. Only pBGP was selectively reduced by smoking and current use of oral contraceptives, respectively. We conclude that there is no appreciable change in BMD before the menopause once skeletal maturity has been reached. Dietary calcium intake increases peak bone density and this positive effect can be potentiated by an active lifestyle. Other putative risk factors had no influence on premenopausal BMD.     

Effect of alcohol consumption on bone mineral density and hormonal parameters in physically active male soldiers

BackgroundPrevious studies on the influence of alcohol intake and smoking on bone mineral density (BMD) in men are inconsistent and the effect of these variables on BMD in physically active men is yet to be explored.ObjectiveTo investigate the influence of alcohol intake and smoking on BMD in a cohort of males with well-defined lifestyle conditions.DesignMen from the armed forces (n = 400) having uniform and defined routines were enrolled. BMD was measured by DXA and participants were grouped according to lifestyle variables. Hormonal parameters were measured by immunoassays.ResultsParticipants with intake of > 24 g/wk of alcohol had significantly higher BMD at femur compared to non-alcohol consumers (p = 0.0001) and a linear increase in mean femoral BMD over increasing categories of alcohol intake (p_trend < 0.0001) was observed. Smoking was negatively associated with femoral BMD. In multiple regression analysis, age, BMI, alcohol consumption and smoking were independent predictors of femoral BMD, explaining 10.6% variance. At lumbar spine, age, height and BMI were independent predictors, explaining 9.4% variance in BMD. The concentrations of total testosterone, free testosterone, bioavailable testosterone and PTH were low (p < 0.0001) whereas estradiol (p = 0.02), free and bioavailable estradiol (p < 0.001) were high in alcohol consumers compared to non-consumers. In multiple regression analysis alcohol intake and height explained 5.5% variance in estradiol_.ConclusionsIn physically active men with well-defined lifestyle conditions, alcohol consumption was associated with higher femoral BMD, the effect of alcohol is complex and is probably partly mediated by influencing the sex steroid levels.     

Alcohol intake and bone status in elderly Japanese men: baseline data from the Fujiwara-kyo osteoporosis risk in men (FORMEN) study

There are no data concerning a relationship between alcohol and bone status from a large-scale community-based study of elderly Japanese men. The baseline survey for the Fujiwara-kyo Osteoporosis Risk in Men Study was performed in 2174 male participants during the period from 2007 to 2008 in Nara Prefecture, Japan. Among them 1665 fitted the following inclusion criteria: (a) age ≥65years, (b) no diseases or drug therapy that could affect bone mineral density (BMD). We analyzed 1421 men with complete information about alcohol intake. We found that alcohol intake and BMD were positively correlated after adjustment for age, body mass index, natto intake, milk intake, smoking, physical activity, education, marital status, and hypertension. Adjusted total hip BMD of men with alcohol intake >39g/day was 0.90g/cm(2) and that of abstainers was 0.85g/cm(2). With regard to bone turnover markers, alcohol intake was inversely associated with serum levels of osteocalcin and tartrate-resistant acid phosphatase isoenzyme 5b. A two-piece linear regression model revealed a positive relationship between alcohol intake and crude mean BMD for the total hip in those with alcohol intake of less than 55g/day. In contrast, alcohol intake and BMD in those with an alcohol intake of 55g/day or more was inversely correlated. The present large-scale study of elderly Japanese men revealed that although an alcohol intake of <55g/day was positively correlated to BMD, alcohol intake of ≥55g/day was inversely correlated to BMD.     

农村男性饮酒量与骨密度相关性研究

目的研究饮酒量对农村男性骨密度的影响。方法选取安徽安庆地区385名农村务农男性为研究对象,设计统一流行病学调查问卷,收集人口统计资料、吸烟、饮酒、文化程度、劳动强度等信息;用双能X线吸收仪(LUNAR PRODIGY SN40160)对研究对象进行骨密度检测。用Kruskal-Wallis秩和检验分析骨密度与吸烟、饮酒、日常体力劳动强度、BMI、文化教育程度之间的关联性;用Spearman相关系数分析骨密度与年龄、腰围、臀围之间的关联性;用多元线性回归分析男性饮酒量与不同部位骨密度关系。结果在调整相关影响因素后,每周饮酒量≤700 g 50°白酒,可明显增加股骨(P0.05)、腰椎(P0.05)和全身(P0.01)的骨密度,随着饮酒量增加对骨密度影响有逐渐减弱趋势,但并未显示降低骨密度的作用。结论农村男性人群适量饮酒可增加骨密度值。     

Smoking and quantitative ultrasound parameters in the calcaneus in 36-year-old men and women

Little is known regarding the association between smoking and quantitative ultrasound (QUS) parameters. Broadband ultrasound attenuation (BUA) and speed of sound (SOS) are believed to provide information on bone quality besides information on bone mineral density (BMD). The aim of this study was to investigate (1) current tobacco smoking; (2) lifetime tobacco smoking; and (3) years since smoking cessation, in relation to QUS and BMD parameters in 36-year-old men and women. Data came from the ninth measurement of the Amsterdam Growth and Health Longitudinal Study (AGAHLS), in which 165 men (36 smokers and 129 nonsmokers) and 178 women (33 smokers and 145 nonsmokers) participated, with an average age of 36 years (SD=0.7). BUA (dB/MHz) and SOS (m/s) of the calcaneus were assessed by using the CUBA Clinical instrument. BMD of the lumbar spine (L1–L4), total hip, and total body were measured with dual-energy X-ray absorptiometry (DXA). We used multiple linear regression analyses with correction for body weight, physical activity, calcium intake, and alcohol consumption. We found no significant associations between smoking and any of the BMD parameters in 36-year-old men and women. However, both current and lifetime tobacco smoking were significantly and negatively associated with BUA in women but not in men. Lifetime tobacco smoking was significantly and negatively associated with SOS in both sexes. The latter association was independent of body weight, calcium intake, physical activity, and alcohol consumption in women, but not in men. Our results suggest that both current and lifetime tobacco smoking are associated with a deterioration in bone quality but not with a reduction in BMD. However, since BMD parameters and QUS parameters were not measured at the same sites, our results may also simply suggest that the calcaneus is affected by smoking at an earlier stage than the lumbar spine, hip, and total body.     

Bone density and lifestyle characteristics in premenopausal and postmenopausal Chinese women

The relationships between bone health and various lifestyle factors were examined in a cross-sectional study in 775 Chinese women aged 35–75 years. Bone mass was significantly positively associated with body weight, height, body mass index (BMI) and duration of breastfeeding, but was not significantly associated with other lifestyle variables, including alcohol consumption, parity, age at menarche and age at menopause after adjusting for age and body weight. A positive association was observed in premenopausal women (but not in postmenopausal women) for bone density with current cigarette smoking and plasma and urinary cotinine (the major metabolite of smoking). However, the confounding effects of other unknown factors present in this cross-sectional study may not be excluded. Daily physical activity, as indicated by time spent working in the fields, was found consistently to be positively associated with bone mass (p<0.0001). When these women were grouped into three physical activity levels on the basis of occupation and daily work intensity, those undertaking heavy labor also had significantly higher radial bone mass than women undertaking light or medium labor. These results suggest a protective effect of daily physical activity on bone health in both pre- and postmenopausal women.     

Differences in bone mineral status between urban and rural Chinese men and women

BACKGROUND: Few studies have investigated differences in bone health and associated lifestyle factors between urban and rural populations in countries, such as China, undergoing rapid nutrition transition. Such a study may help to identify risk factors of osteoporosis and provide evidence for future preventive strategies. OBJECTIVE: To determine primarily whether differences in bone mineral content (BMC) and bone mineral density (BMD) exist between urban and rural Chinese men and women and secondly whether any urban-rural differences could be explained by body size or lifestyle factors. METHODS: In total, 490 men and 689 women aged 50-70 were included in the study. 535 of them were from urban Shanghai and 644 from surrounding rural areas. Anthropometric measurements were conducted and spine lumber 1-4 BMC measurements were determined by dual-energy X-ray absorptiometry (DEXA). Information on socioeconomic status, medical history, smoking and drinking habits and physical activity were collected. RESULTS: Urban men and women had significantly higher spine BMC, BMD and bone area than their rural counterparts (P<0.01). After controlling body size, the differences between urban-rural spine BMC and BMD remained in women (P<0.001), but were no longer significant in men. The urban and rural differences of BMC and BMD in women could not be explained by including the lifestyle factors such as income, intake of milk, vitamin D and calcium, total physical activity level, walking and social activity. CONCLUSION: This study found the significant differences in both spine BMC and BMD between urban and rural men and women in Shanghai, China. This difference could be explained by the body size in men; however, it remained unexplained in women after adjusting for body size and certain lifestyle risk factors.     

中老年女性骨密度相关因素的临床分析

目的　分析中老年女性骨密度的相关因素。方法　从 2 0 0 1年 9月至 2 0 0 2年 8月分层随机抽样 10 90名妇女 ,询问病史、体检 ,按 1∶3的比例随机抽样 330名妇女 ,用双能X线骨密度仪测量其骨密度。结果　随着年龄的增大和绝经年限的延长 ,妇女的骨密度逐渐下降 ,其骨密度值与年龄、绝经年限、初潮年龄、月经周期天数、孕、产次、产后哺乳月数、吸烟、喝酒呈显著负相关 (P <0 . 0 5 ) ,与身高、体重、体重指数呈显著正相关 (P <0. 0 5 )。用逐步回归的方法进行分析 ,年龄、绝经后年限、喝骨头汤量可以进入方程。结论　妇女的骨密度在 4 0岁以上逐渐降低 ,年龄越大、绝经年限越长、孕产次越多、产后哺乳时间越长、有吸烟喝酒习惯者 ,其骨密度较低 ;而体重、体重指数越大 ,其骨密度较高。     

Age, body mass index, current smoking history, and serum insulin-like growth factor-I levels associated with bone mineral density in middle-aged Korean men

Osteoporosis is a growing health problem in women and in men. This cross-sectional study examined the association of anthropometric, lifestyle, and hormonal factors with bone mineral density (BMD) in 152 healthy Korean middle-aged men. Smoking habits and alcohol consumption were assessed by interview. Serum testosterone and insulin-like growth factor-I (IGF-I) levels were measured by radioimmunoassay, and serum growth hormone (GH) levels were measured by immunoradiometric assay. GH stimulation tests were performed after the ingestion of 500mg of L-dopa. BMD was measured at the lumbar spine and at the femoral neck by dual-energy X-ray absorptiometry. Of the middle-aged men, 3.9% were osteoporotic and 28.3% were osteopenic at the lumbar spine site, and 5.9% were osteoporotic and 45.4% were osteopenic at the femoral neck site. Lumbar spine BMD correlated significantly with body mass index (BMI), and femoral neck BMD correlated significantly with age, BMI, and serum IGF-I levels. The lowest quartile group for serum IGF-I levels showed the lowest femoral neck BMD. Osteoporotic men by lumbar spine BMD showed significant differences from the normal BMD group in terms of BMI and smoking habits. Also, osteoporotic men by femoral neck BMD were significantly different for mean age, BMI, and serum IGF-I levels compared with the normal BMD group. On multiple regression analysis, BMI was found to be the only independent predictor of lumbar spine BMD, whereas both BMI and serum IGF-I levels were found to be the independent predictors of femoral neck BMD. Overall, 28.3%–45.4% of middle-aged Korean men were osteopenic. We suggest that higher age, a lower BMI, current smoking history, and lower serum IGF-I levels are risk factors for lower BMD in middle-aged Korean men; however, serum testosterone levels and GH secretory capacity were not found to be correlated with BMD.     

Interactions among age, adiposity, bodyweight, lifestyle factors and sex steroid hormones in healthy Singaporean Chinese men

Aim： To examine the inter-relationships among age, lifestyle factors, anthropometric parameters, percent body fat and steroid hormone parameters in 531 healthy Singaporean Chinese men aged between 29 and 72 years old. Methods： Various lifestyle parameters were quantified through a survey, and testosterone （T）, estradiol （E2）, dehydroepiandrosterone sulphate （DHEAS） and sex hormone binding globulin （SHBG） were measured using established methods. Anthropometric parameters were collected and computed, and percent body fat （Siri） was measured using the DEXA scanner. Results： SHBG, DHEAS, bioavailable-T （Bio-T）, E2, Siri, Ht, W/H, W/Ht and work stress were independently correlated with age. Using multivariate analyses and adjusting for age and other related factors, exercise, smoking and alcohol consumption have positive impacts on androgen levels and body composition. However, black and green tea consumption was associated with negative effects on body composition and with higher levels of E2 and Free Estradiol Index （FEI）. Men with shorter sleep duration had significantly lower T levels as compared to those with 6 h or more of nightly sleep. Higher T levels were associated with lower levels of adiposity and other indices of adiposity, whereas higher E2 levels were related to higher levels of adiposity. Men with higher DHEAS were significantly taller and heavier than those with low DHEAS levels. Conclusion： The study showed the close interactions among the gonadal/adrenal and metabolic compartments, with age being a key determinant in their interactions. Lifestyle factors such as exercise, smoking, sleeping and alcohol and tea consumption might play significantly roles in determining the status of health in men.     

Smoking among premenopausal women is associated with increased risk of low bone status: the JPOS Study

The impact of smoking on peak bone density has not been conclusively established. We examined how smoking exposure influences bone mineral density (BMD) or the risk of low bone status in premenopausal women. We conducted a baseline survey with a representative sample of Japanese women in 1996. The effect of current and former smokers (ever-smoker) was investigated with 789 premenopausal women aged 20–40 years. The multiple regression with stepwise method was used to identify significant determinants for BMD or the risk of low bone status (T-score < −1) with age, height, weight, calcium intake, coffee consumption, exercise habits, level of daily activity, parity ≥ 1, and smoking as explanatory variables. The smoking effect was determined after adjusting for age, height, weight, and significant variables in the multiple regression with stepwise method. Ever-smoker was significantly associated with decreased lumbar BMD adjusted for age, height, and weight. The odds ratio of an ever-smoker for low bone status at the lumbar spine was 2.03 (95% CI 1.12, 5.82) adjusted for age, height, weight, and parity. The odds ratio for low bone status at the lumbar spine was 1.59 (95% CI 0.65, 3.91) and 2.55 (95% CI 1.12, 5.82) in those with less than 3 pack-years of tobacco use and in those with 3 or more pack-years of tobacco use, respectively. These values were adjusted for age, height, weight, and parity using a never-smoker as a reference. Cumulative smoking exposure may be associated with increased risk of low bone status among premenopausal women.     

Lifelong risk factors for osteoporosis and fractures in elderly women with low body mass index--a population-based study

Low body weight is associated with an increased risk for osteoporosis and fractures, but the contribution of other lifestyle related factors have not been previously studied within lean elderly women. The present study evaluated the association between lifelong lifestyle factors and bone density, falls and postmenopausal fractures in elderly women with low body mass index (BMI). A population-based sample of 1,222 women aged 70 to 73 years was stratified by BMI tertiles, and all 407 women in the lowest tertile participated. Data on falls and postmenopausal fractures, physical activity, functional capacity, calcium intake, smoking, alcohol intake and medical factors at different ages were obtained by a questionnaire. Calcaneum bone mass as broadband ultrasound attenuation (BUA) was assessed with a quantitative ultrasound (QUS) device, and bone mineral density (BMD) at the distal radius was measured with a dual-energy X-ray absorptiometry (DXA). Low current physical activity was associated with lower calcaneum BUA and factors associated with higher BUA were body weight, low lifetime occupational physical activity, hormone replacement and type 2 diabetes. Weight, type 2 diabetes and thiatzide use were associated with higher radius BMD. The final multivariate model consisted of four independent factors associated with fractures: low lifetime habitual physical activity (OR 3.7, 95% CI 1.9-7.1), diabetes (OR 0.2, 95% CI 0.1-1.0), living alone (OR 1.7, 95% CI 1.0-3.0) and calcaneum BUA (1.8, 95% CI 1.3-2.4). Poor functional ability and symptoms of depression were associated with recent falling. In elderly women with low BMI, lifelong physical activity may protect from fractures, while low calcaneum bone mass and living unpartnered appear to be associated with an increased risk for fractures. Poor functional ability and presence of depression may be associated with risk of falling. Type 2 diabetes may modify the risk of low bone mass and low-trauma postmenopausal fractures. Albeit that the results of this study need to be confirmed in prospective follow-up studies, multifactorial program with the emphasis on physical and social activation in the primary care setting for preventing falls and fractures in lean elderly women is recommended.     

苏南地区中青年男性人群骨密度及其生活习惯的相关性研究

目的调查苏南地区中青年男性体检人群骨密度及其与生活习惯的相关性,为本地区骨质疏松防治提供参考依据。方法选择2014年7月至2015年10月间1578例在我院体检的苏南地区≤60岁男性人群为研究对象,采用美国HOLOGIC公司的Discovery WI骨密度仪对受试者L1-L4椎体进行骨密度检测,同时自行设计调查表进行问卷。将824例骨质减少人群作为病例组,将754例骨质正常人群作为对照组进行研究。采用IBM SPSS19.0统计软件进行分析,以P0.05为差异有统计学意义。结果苏南地区男性人群在26~30岁形成腰椎骨量峰值,之后BMD逐渐下降,46岁以后BMD下降加速。运动、喝牛奶、吸烟及饮酒与骨质减少与否有关,差异有统计学意义(P0.05)。苏南地区中青年男性人群每天运动大于30 min的占31.115%、每天喝牛奶的占27.82%,而每天抽烟的占50.76%、每天喝酒的占43.346%。结论喝牛奶及30 min/d的运动是骨质健康的保护因素,吸烟和饮酒是骨质健康的危害因素。苏南地区中青年男性人群要改善现有的生活方式。     

Determinants of bone mineral density in Chinese men

Osteoporotic fractures are increasing among Asian populations in both genders, but the risk factors for low bone mineral density (BMD) in Asian men is unclear. To determine the hormonal and lifestyle risk factors for low BMD in Asian men, we studied 407 community-dwelling southern Chinese men aged 50 years and above. Medical history and lifestyle habits were obtained with a structured questionnaire. Dietary calcium and phytoestrogen intake were assessed by a semi-quantitative questionnaire. BMD at the spine and hip were measured by dual-energy X-ray absorptiometry (DXA). Fasting blood was analyzed for 25(OH)D, parathyroid hormone (PTH), total and bioavailable estradiol (bio-E) and testosterone (bio-T). The mean age of the cohort was 68.42±10.4 (50–96) years. In the linear regression model, weight, age, body mass index (BMI), bio-E, PTH, cigarette smoking and weight-bearing exercise were significant determinants of total hip BMD. Together they explained 55% of the total variance of hip BMD, with body weight being the most important determining factor. With age and weight adjustment, height, bio-T and flavonoid intake were identified as additional determinants of total hip BMD. Strategies to prevent bone loss and osteoporosis in Asian men should include lifestyle modification and maintenance of hormonal sufficiency.     

Cigarette Smoking, Alcohol and Caffeine Consumption, and Bone Mineral Density in Postmenopausal Women

The aim of this analysis was to compare the effects of different measures of cigarette, alcohol and caffeine consumption upon bone mineral density (BMD). Five hundred and eighty postmenopausal women aged 45–59 years at recruitment completed a risk factor questionnaire that contained detailed sections on cigarette, alcohol and caffeine consumption. BMD was measured using dual-energy X-ray absorptiometry. Measurements taken at five bone sites were used: anterior-posterior spine, femoral neck, greater trochanter, radius/ulna and whole body. The data were analyzed using multiple linear regression, adjusting for a number of established BMD risk factors. BMD was more strongly related to the number of months spent smoking than to pack-years of smoking at all five sites (p <0.05 at four of the five sites). There were significant reductions in BMD when comparing smokers with non-smokers at ages 20, 30 and 40 years, but not for current smoking. Lifetime alcohol consumption and current alcohol consumption did not have an independent association with BMD. However, the heaviest beer drinkers in the sample had a particularly low bone density. Caffeine consumption at various ages was not associated with BMD. The results of these analyses suggest that for predicting BMD a simple history of smoking duration is as good as trying to obtain more detailed smoking information, but that only 25% of the variation in BMD is explained by personal characteristics, family history and lifestyle factors. Received: 30 June 1997 / Accepted: 23 December 1997     

长春市24831例前臂远端骨密度影响因素研究

目的研究年龄、性别、体重指数(BMI)、饮食、运动、吸烟、嗜酒、慢性胃炎、糖尿病、高血压、甲状腺机能亢进、父亲骨折病史、母亲骨折病史及女性生育、绝经等因素对骨密度(BMD)的影响。方法双能X线骨密度仪(pDXA)检测前臂远端BMD,用自制的问卷调查表记录受试者生活习惯、慢性病史及女性绝经、生育史等进行统计学分析。结果年龄、性别、体重、运动、饮食、吸烟、嗜酒、慢性胃炎、高血压病、甲状腺机能亢进及母亲骨折病史与BMD检测值相关,具有统计学意义;而父亲骨折病史、Ⅱ型糖尿病病史与BMD无关,女性绝经年限和生育次数与BMD呈明显负相关。结论吸烟、嗜酒、母亲骨折病史、慢性胃炎、甲状腺机能亢进、高血压病史及女性绝经、生育次数是OP的危险因素。运动、喝牛奶、吃海产品、体重指数是OP的可控因素。     

中国老年男性骨质疏松症影响因素的Meta分析

目的 通过Meta分析明确中国老年男性罹患骨质疏松(osteoporosis,OP)的主要影响因素.方法 使用计算机检索中国知网、万方数据库、维普网、PubMed、Web of Science、Embase数据库(自建库以来至2020年1月),并使用NOS进行文献质量评价,使用RevMan 5.3进行Meta分析.结果...     

Impacts of Body Mass Index,Physical Activity,and Smoking on Femoral Bone Loss: The Tromsø Study

Bone mineral density (BMD) is a reflection of bone strength and lifestyles that preserve bone mass and may reduce fracture risk in old age. This study examined the effect of combined profiles of smoking, physical activity, and body mass index (BMI) on lifetime bone loss. Data were collected from the population‐based Tromsø Study. BMD was measured as g/cm² by dual‐energy X‐ray absorptiometry (DXA) at the total hip and femoral neck in 2580 women and 2084 men aged 30 to 80 years in the 2001–02 survey, and repeated in 1401 women and 1113 men in the 2007–08 survey. Height and weight were measured and lifestyle information was collected through questionnaires. Data were analyzed using linear mixed models with second‐degree fractional polynomials. From the peak at the age around 40 years to 80 years of age, loss rates varied between 4% at the total hip and 14% at femoral neck in nonsmoking, physically active men with a BMI of 30 kg/m² to approximately 30% at both femoral sites in heavy smoking, physically inactive men with a BMI value of 18 kg/m². In women also, loss rates of more than 30% were estimated in the lifestyle groups with a BMI value of 18 kg/m². BMI had the strongest effect on BMD, especially in the oldest age groups, but a BMI above 30 kg/m² did not exert any additional effect compared with the population average BMI of 27 kg/m². At the age of 80 years, a lifestyle of moderate BMI to light overweight, smoking avoidance, and physical activity of 4 hours of vigorous activity per week through adult life may result in 1 to 2 standard deviations higher BMD levels compared with a lifestyle marked by heavy smoking, inactivity, and low weight. In the prevention of osteoporosis and fracture risk, the effect of combined lifestyles through adult life should be highlighted. © 2014 American Society for Bone and Mineral Research.     

Characterization of Genetic and Lifestyle Factors for Determining Variation in Body Mass Index, Fat Mass, Percentage of Fat Mass, and Lean Mass

In this study, we simultaneously characterized genetic and lifestyle factors (exercise, smoking, and alcohol consumption) in determining variation in body mass index (BMI), fat mass, percentage of fat mass (PFM), and lean mass while adjusting for the effects of age and sex. Six hundred fifty-eight Caucasian individuals from 48 pedigrees were studied for BMI. Among these individuals, 289 from 38 pedigrees were studied for fat mass, PFM, and lean mass measured by dual X-ray absorptiometry (DXA). After adjusting for age, sex, and lifestyle factors, the heritabilities (h(2)) of BMI, fat mass, PFM, and lean mass ranged from 0.52 to 0.57 with associated standard errors ranging from 0.09 to 0.14. After accounting for significant sex and age effects, exercise had significant effects for all the phenotypes studied, and the effects of smoking and alcohol consumption were not significant. Therefore, significant proportions of variation in BMI, fat mass, PFM, and lean mass were under genetic control, and exercise had a significant effect in reducing BMI, fat mass, and PFM and in increasing lean mass. This study warrants further genetic linkage analyses to search for genes for the obesity-related phenotypes measured by DXA in our population.