Coffee, tea and caffeine consumption in relation to osteoporotic fracture risk in a cohort of Swedish women

Common questions and misconceptions about caffeine supplementation: what does the scientific evidence really show?

Caffeine is a popular ergogenic aid that has a plethora of evidence highlighting its positive effects. A Google Scholar search using the keywords "caffeine" and "exercise" yields over 200,000 results, emphasizing the extensive research on this topic. However, despite the vast amount of available data, it is intriguing that uncertainties persist regarding the effectiveness and safety of caffeine. These include but are not limited to: 1. Does caffeine dehydrate you at rest? 2. Does caffeine dehydrate you during exercise? 3. Does caffeine promote the loss of body fat? 4. Does habitual caffeine consumption influence the performance response to acute caffeine supplementation? 5. Does caffeine affect upper vs. lower body performance/strength differently? 6. Is there a relationship between caffeine and depression? 7. Can too much caffeine kill you? 8. Are there sex differences regarding caffeine's effects? 9. Does caffeine work for everyone? 10. Does caffeine cause heart problems? 11. Does caffeine promote the loss of bone mineral? 12. Should pregnant women avoid caffeine? 13. Is caffeine addictive? 14. Does waiting 1.5-2.0 hours after waking to consume caffeine help you avoid the afternoon "crash?" To answer these questions, we performed an evidence-based scientific evaluation of the literature regarding caffeine supplementation.

The potential application of fermented tea as a drink for regulating bone mass

Currently, there is evidence to suggest the benefits of drinking fermented tea for people with osteoporosis, and based on this, many studies have been conducted on the dosage, exact ingredients, mechanisms, and industrial applications of fermented tea for protecting against osteoporosis. A summary and analysis of studies on the regulation of bone mass by oolong tea, black tea, and their active ingredients (including 39 known catechin compounds) was conducted. It was found that the regulation of bone mass by fermented tea is backed by evidence from epidemiology, animal experiments, and cell experiments. The main active components of fermented tea are tea polyphenols, tea pigments, and trace amino acids. The specific mechanisms involved include regulating bone marrow mesenchymal stem cell osteogenesis, inhibiting osteoclast activity, promoting calcium and phosphorus absorption, reducing inflammation levels, regulating gut microbiota, regulating endocrine function, and inhibiting oxidative stress. In terms of its application, extraction, precipitation, biosynthesis and membrane separation method are mainly used to separate the active ingredients of anti osteoporosis from fermented tea. In conclusion, fermented tea has sufficient theoretical and practical support for regulating bone mass and preventing osteoporosis, and is suitable for development as a health supplement. At the same time, a large amount of epidemiological evidence is needed to prove the specific dosage of tea consumption.

Caffeine regulates both osteoclast and osteoblast differentiation via the AKT, NF-κB, and MAPK pathways

Background: Although caffeine generally offers benefits to human health, its impact on bone metabolism remains unclear. Aim and Methods: This study aimed to systematically evaluate the long-term effects of caffeine administration on osteoclasts, osteoblasts, and ovariectomy-induced postmenopausal osteoporosis (OP). Results: Our in vitro findings revealed that 3.125 and 12.5 μg/mL caffeine inhibited RANKL-mediated osteoclastogenesis in RAW 264.7 cells through the MAPK and NF-κB pathways, accompanied by the inactivation of nuclear translocation of nuclear factor NFATc1. Similarly, 3.125 and 12.5 μg/mL of caffeine modulated MC3T3-E1 osteogenesis via the AKT, MAPK, and NF-κB pathways. However, 50 μg/mL of caffeine promoted the phosphorylation of IκBα, P65, JNK, P38, and AKT, followed by the activation of NFATc1 and the inactivation of Runx2 and Osterix, ultimately disrupting the balance between osteoblastogenesis and osteoclastogenesis. In vivo studies showed that gavage with 55.44 mg/kg caffeine inhibited osteoclastogenesis, promoted osteogenesis, and ameliorated bone loss in ovariectomized mice. Conclusion: Conversely, long-term intake of high-dose caffeine (110.88 mg/kg) disrupted osteogenesis activity and promoted osteoclastogenesis, thereby disturbing bone homeostasis. Collectively, these findings suggest that a moderate caffeine intake (approximately 400 mg in humans) can regulate bone homeostasis by influencing both osteoclasts and osteoblasts. However, long-term high-dose caffeine consumption (approximately 800 mg in humans) could have detrimental effects on the skeletal system.

Tea intake and total body bone mineral density of all ages: a Mendelian randomization analysis

Background

There is increasing evidence indicating that tea intake affects bone mineral density levels; however, the causality between tea intake and bone mineral density is inconclusive. This study aimed to assess the causal relationship between tea intake and total body bone mineral density (TB-BMD) through two-sample Mendelian randomization (MR) analysis.

Methods

We conducted a two-sample MR approach to estimate the potential causal effects of tea intake on TB-BMD at all ages in a European population. The analyses were performed using summary statistics obtained for single-nucleotide polymorphisms (SNPs), identified from a genome-wide association meta-analysis of tea intake (N = up to 447,485 individuals) and from the GEnetic Factors for OSteoporosis (GEFOS) Consortium's genome-wide association meta-analysis (N = up to 56,284 individuals), with baseline data collected in 2018 and populations derived from the European ancestry. The association between each SNP and TB-BMD was weighted by its association with tea intake, and estimates were combined mainly using an inverse-variance weighted meta-analysis. In addition, we explored the potential causal effects between green tea intake, herbal tea intake, and TB-BMD.

Results

The MR analysis revealed that genetically determined tea intake exerts a causal impact on TB-BMD, with an odds ratio (OR) of 1.204 (95% CI: 1.062-1.366, p = 0.004), especially in the age group of 45-60 years (OR = 1.360, 95% CI: 1.088-1.700, p = 0.007). No horizontal pleiotropy and heterogeneity were observed. However, there was no causal effect of tea intake on TB-BMD in the age groups of 0-15, 15-30, 30-45, and over 60 years. In the subgroup analysis, when green tea intake was regarded as the exposure factor, no salient associations were found between green tea consumption and TB-BMD (IVW p = 0.368). Similarly, there was also no causal association between herbal tea intake and TB-BMD (IVW p = 0.264).

Conclusion

The findings of this study support the evidence that tea consumption increases bone density and reduces the risk of osteoporosis in the age group of 45-60 years within the European population.

Hyperparathyroidism, Serum Phosphorus and Dietary Intake in Hemodialysis Patients: Is There a Novel Relationship?

The management of hyperparathyroidism (intact parathyroid hormone (iPTH) serum levels > 585 pg/mL), frequently focuses on the appropriate control of mineral and bone markers, with the decrease in serum and dietary phosphorus as two of the targets. We aimed to investigate the association between iPTH, serum phosphorus levels and dietary intake. This was a cross-sectional, multicenter, observational study with 561 patients on hemodialysis treatment. Clinical parameters, body composition and dietary intake were assessed. For the analysis, patients were divided into three groups: (a) iPTH < 130, (b) iPTH between 130 and 585 and (c) iPTH > 585 pg/mL. The association between PTH, serum phosphorus and dietary intake was analyzed using linear regression models. In the whole sample, 23.2% of patients presented an iPTH > 585 pg/mL. Patients with higher iPTH levels were those with longer HD vintage and lower ages, higher serum phosphorus, serum calcium, Ca/P product, albumin and caffeine intake, and a lower dietary intake of phosphorus, fiber, riboflavin and folate. Higher serum phosphorus predicted higher iPTH levels, even in the adjusted model. However, lower dietary phosphorus and fiber intake were predictors of higher iPTH levels, including in the adjusted model. Our results bring new data to the relationship between dietary intake and iPTH values. Despite higher serum phosphorus being observed in patients with HPTH, an opposite association was noted regarding dietary phosphate and fiber.

Analyzing the factors associated with efficacy among teriparatide treatment in postmenopausal women with osteoporosis

BACKGROUND

Teriparatide (TPTD) is a widely used anabolic agent for the treatment of osteoporosis. Several factors have been identified to be related to bone mineral density (BMD) increase in anti-osteoporosis treatment with other agents; however, there has been no systematic analysis to summarize the associated determinants of BMD reaction to daily teriparatide treatment.

METHODS

In this retrospective study, we performed a comprehensive investigation involving not only clinical data but also several relevant lifestyle factors to be examined for their potential contribution to BMD response. This post-hoc analysis included 258 post-menopaused patients with osteoporosis who received TPTD at 20 µg/day for 12 months. Univariate and multivariate analyses were conducted to distinguish the response variables of lumbar spine (LS) BMD transformation, the principal outcome measure of efficacy, from the baseline at 12 months.

RESULTS

Twelve months of TPTD treatment resulted in an absolute 0.39 ± 0.37 increase in T-score of LS BMD. Gastrointestinal disease, prior bisphosphonate or glucocorticoid treatment, no vitamin K2 supplementation, low levels of serum 25(OH)D and PINP, weak increment of PINP and β-CTX at 3 months, unhealthy lifestyle (excessive smoking, tea, coffee, and drinking), vegetarian diet pattern, low ALT level, and high BMD at baseline were determined by univariate analyses to be related to the weak reaction of TPTD treatment (P < 0.10). In the multiple regression model, postmenopausal women with vitamin K2 supplementation, higher baseline serum 25(OH)D level, and higher PINP concentration at 3 months indicated a good reaction of LS BMD at 12 months (P < 0.05). Patients with gastrointestinal disease, prior bisphosphonate and glucocorticoid treatment, vegetarian diet pattern, and higher baseline BMD were significantly more likely to have a lower absolute LS BMD response compared to patients without these characteristics (P < 0.05). Further analysis confirmed the negative effect of unhealthy lifestyle on TPTD treatment.

CONCLUSION

Our results emphasize the significance of a comprehensive assessment of clinical or lifestyle-related characteristics of postmenopausal women with osteoporosis in the management of TPTD therapy in routine care.

Summary of best evidence for self-management in postoperative osteoporotic fracture patients

Osteoporotic fracture as a serious complication of osteoporosis which is usually treated surgically, and its recovery is closely related to one's own behavior and lifestyle, and is a long-term, complex management process that often requires the individual to self-manage many health-related factors.

OBJECTIVE

To gather and synthesize the most robust evidence regarding self-management in patients with postoperative osteoporotic fractures, in order to provide scientific, evidence-based guidance for clinical healthcare professionals to assist postoperative patients in self-management efforts, and to assist patients in optimizing their self-management practices and behavioral norms.

METHODS

Based on the "6 S" pyramid model of evidence resources (System, Summaries, Synopses of synthesis, Syntheses, Synopses of studies, Studies), we searched the Up To Date, BMJ Best Practice, The Cochrane Library, Australian Joanna Briggs Institute JBI Evidence-Based Medicine Center Healthcare Database, National Institute for Health and Clinical Excellence (NICE), Guidelines International Network (GIN), National Guideline Clearinghouse (NGC) and Scottish Intercollegiate Guide lines Network (SIGN), MedPulse, Embase, PubMed, CINAHL, Web of Science, SinoMed, Chinese Medical Journal Full Text Database, CNKI, Wanfang Data Knowledge Service Platform, and VIP database, etc, The search period for clinical decision-making, systematic evaluation, clinical guidelines, evidence summaries and expert consensus on self-management of postoperative osteoporotic fracture patients, and it was from the establishment of the database to 18 February 2023. To ensure the quality of the literature, three researchers strictly screened the literature according to the literature inclusion and exclusion criteria, and two or more researchers independently evaluated the quality of the included literature, and extracted and integrated the relevant evidence.

RESULTS

Thirteen documents were finally included, including 4 clinical practice guidelines, 5 expert consensus, 2 recommended practices, 1 systematic evaluation, and 1 clinical decision report. The research team summarized the evidence in 6 dimensions: multidisciplinary teamwork, management of daily living, management of treatment adherence, management of exercise, management of fall prevention and subsequent fracture, and management of emotions, and 33 pieces of evidence were extracted.

CONCLUSION

The study summarized 33 best evidence of self-management in postoperative osteoporotic fracture patients, which provides a scientific and reasonable self-management program for postoperative patients, and also provides important reference and information for clinical healthcare professionals to provide more comprehensive and scientific self-management health education to patients.

The relationship between caffeine and its metabolites and bone mineral density in postmenopausal women: a cross-sectional analysis from the NHANES database

We aim to explore the association between caffeine and its metabolites and bone mineral density (BMD) in postmenopausal women. Data of 4286 postmenopausal women were extracted from the National Health and Nutrition Examination Survey (NHANES) database in 2009-14 in this cross-sectional study. Weighted linear regression and stepwise regression analyses were used to screen the covariates. Weighted univariate and multivariate linear regression analyses were used to explore the associations between caffeine and its metabolites and BMD. The evaluation index was estimated value (β) with 95 % confidence intervals (CIs). We also explored these relationships in age subgroups. The median BMD level among the eligible women was 0⋅7 gm/cm2. After adjusting for covariates including age, body mass index (BMI), fat intake, Calcium (Ca) supplements, diabetes mellitus (DM), angina pectoris, parental history of osteoporosis (OP), anti-osteoporosis therapy, poverty income ratio (PIR), vitamin D (VD) supplements, coronary heart disease (CHD), and previous fracture, we found that caffeine intake was not significantly related to the BMD reduction (β = 0, P = 0⋅135). However, caffeine metabolites, including MethyluricAcid3, MethyluricAcid7, MethyluricAcid37, Methylxanthine3, and Methylxanthine37, were negatively associated with the BMD (all P < 0⋅05). In addition, MethyluricAcid37 and Methylxanthine37 were negatively associated with BMD in females aged <65 years old, while MethyluricAcid3 and Methylxanthine3 were noteworthy in those who aged ≥65 years old. The roles of caffeine and its metabolites in BMD reduction and OP in postmenopausal women needed further exploration.

Tea consumption and risk of bone health: an updated systematic review and meta-analysis

INTRODUCTION

Current research evaluating the association between tea consumption and bone health still has inconsistent findings.

MATERIALS AND METHODS

The electronic databases of Embase, PubMed, Scopus, and Web of Science were systematically searched from inception until December 2022 to identify eligible studies. The calculation of summary relative risks (RRs) and 95% confidence intervals (CIs) was carried out using random-effects models. I2 statistics and Forest plots were used to assess the heterogeneity of RR values across studies.

RESULTS

The pooled relative risks for bone health-related outcomes of interest among tea drinkers, compared to non-drinkers, were 0.910 (95% confidence interval 0.845 to 0.980) for fractures, based on 20 studies, 0.332 (0.207-0.457) for BMD (13 studies), 0.800 (0.674-0.950) for osteoporosis (10 studies), and 1.006 (0.876-1.156) for osteopenia (5 studies). Subgroup analysis of locations showed that the pooled relative risks were 0.903 (0.844-0.966) for the hip, 0.735 (0.586-0.922) for the femur, 0.776 (0.610-0.988) for the lumbar, 0.980 (0.942-1.021) for the forearm and wrist, 0.804 (0.567-1.139) for the phalanges, and 0.612 (0.468-0.800) for Ward's triangle. One-stage dose-response analysis revealed that individuals who consumed less than 4.5 cups of tea per day had a lower risk of bone health-related outcomes than those who did not consume tea, with statistically significant results.

CONCLUSION

There is an association between tea consumption and a reduced risk of fractures, osteoporosis, hip, femur, and lumbar, as well as increased BMD.

The efficacy of polyphenols as an antioxidant agent: An updated review

Global production of the two major poultry products, meat and eggs, has increased quickly. This, in turn, indicates both the relatively low cost and the customers' desire for these secure and high-quality products. Natural feed additives have become increasingly popular to preserve and enhance the health and productivity of poultry and livestock. We consume a lot of polyphenols, which are a kind of micronutrient. These are phytochemicals with positive effects on cardiovascular, cognitive, anti-inflammatory, detoxifying, anti-tumor, anti-pathogen, a catalyst for growth, and immunomodulating functions, among extra health advantages. Furthermore, high quantities of polyphenols have unknown and occasionally unfavorable impacts on the digestive tract health, nutrient assimilation, the activity of digestive enzymes, vitamin and mineral assimilation, the performance of the laying hens, and the quality of the eggs. This review clarifies the numerous sources, categories, biological functions, potential limitations on usage, and effects of polyphenols on poultry performance, egg composition, exterior and interior quality traits.

Association of Coffee and Tea Intake with Bone Mineral Density and Hip Fracture: A Meta-Analysis

Background and Objectives: Osteoporosis is characterized by low bone mass and high bone fragility. Findings regarding the association of coffee and tea intake with osteoporosis have been inconsistent. We conducted this meta-analysis to investigate whether coffee and tea intake is associated with low bone mineral density (BMD) and high hip fracture risk. Materials and Methods: PubMed, MEDLINE, and Embase were searched for relevant studies published before 2022. Studies on the effects of coffee/tea intake on hip fracture/BMD were included in our meta-analysis, whereas those focusing on specific disease groups and those with no relevant coffee/tea intake data were excluded. We assessed mean difference (MD; for BMD) and pooled hazard ratio (HR; for hip fracture) values with 95% confidence interval (CI) values. The cohort was divided into high- and low-intake groups considering the thresholds of 1 and 2 cups/day for tea and coffee, respectively. Results: Our meta-analysis included 20 studies comprising 508,312 individuals. The pooled MD was 0.020 for coffee (95% CI, -0.003 to 0.044) and 0.039 for tea (95% CI, -0.012 to 0.09), whereas the pooled HR was 1.008 for coffee (95% CI, 0.760 to 1.337) and 0.93 for tea (95% CI, 0.84 to 1.03). Conclusions: Our meta-analysis results suggest that daily coffee or tea consumption is not associated with BMD or hip fracture risk.

Association of Self-Reported Sleep Characteristics and Hip Fracture: Observational and Mendelian Randomization Studies

Previous observational studies on the relationship between sleep characteristics and fracture have yielded contradictory results. The goal of this study was to replicate the findings in a large longitudinal cohort and then conduct a Mendelian randomization (MR) analysis to infer the causality between sleep behaviors and fracture risk. Based on data from the China Health and Retirement Longitudinal Study (CHARLS) including 17,708 participants, we found that individuals with short sleep duration (<5 h) (OR [odds ratio] = 1.62, 95% CI: 1.07-2.44) or restless sleep (OR = 1.55, 95% CI: 1.10-2.19) have a higher risk of hip fracture. A U-shaped relationship between nighttime sleep duration and hip fracture risk (p-nonlinear = 0.01) was observed using restricted cubic spline regression analysis. Through joint effect analysis, we found that participants with short sleep duration (<5 h) combined with midday napping could significantly decrease hip fracture incidence. We further inferred the causal relationship between self-reported sleep behaviors and hip fracture using the MR approach. Among four sleep phenotypic parameters (sleep duration, daytime napping, chronotype, and insomnia), we found a modest causal relationship between sleep duration and fracture (OR = 0.69, 95% CI: 0.48 to 0.99, p = 0.04). However, no causal relationship was observed for other sleep traits. In conclusion, our findings suggest that short sleep duration has a potential detrimental effect on hip fracture. Improving sleep patterns is of significance for developing hip fracture preventive strategies in the middle-aged and the elderly populations.

Tea consumption and the risks of osteoporosis and hip fracture: a population-based longitudinal follow-up study

This population-based longitudinal follow-up study showed a protective effect of tea consumption against osteoporosis, particularly among women and middle-aged people. High tea consumption was also associated with a reduced risk of hip fracture.

INTRODUCTION

To investigate the association of tea consumption with the risks of osteoporosis and hip fracture.

METHODS

This study used the Keelung Community-based Integrated Screening database and Taiwan's National Health Insurance Research Database. A total of 42,742 subjects aged 45 to 74 years were enrolled. Each was classified as no tea consumption, low tea consumption, and high tea consumption, according to the results of an eating habits questionnaire. The diagnosis of osteoporosis and hip fracture was based on BMD measured by dual-energy X-ray absorptiometry and the X-ray findings. The median follow-up time was 8.5 years.

RESULTS

As compared with the no tea consumption group, the osteoporosis HRs for the low tea consumption and high tea consumption groups were 0.88 (95% confidence interval (CI) 0.80-0.96) and 0.87 (95% CI 0.80-0.94), respectively. Among those participants aged 59 or below, the osteoporosis HRs for low tea consumption and high tea consumption (vs. no tea consumption) were 0.85 (95% CI 0.74-0.96) and 0.79 (95% CI 0.69-0.90). The HRs of hip fracture for the low tea consumption and high tea consumption groups (vs. no tea consumption) were 0.85 (95% CI 0.67-1.08) and 0.69 (95% CI 0.55-0.86), respectively.

CONCLUSION

Tea consumption was linked to a lower risk of osteoporosis, particularly among women and middle-aged people. High tea consumption was also associated with a reduced risk of hip fracture.

The association of coffee consumption with the risk of osteoporosis and fractures: a systematic review and meta-analysis

To elucidate the association of coffee and bone health would help fracture risk reduction via dietary intervention. Although those who had higher coffee consumption were less likely to have osteoporosis, the associations between coffee consumption and fracture risk need further investigations with better study designs.

INTRODUCTION

The associations between coffee consumption and the risk of osteoporosis and fracture remain inconclusive. We aimed to better quantify these associations by conducting meta-analyses of observational studies.

METHODS

Relevant studies were systematically searched on PubMed, Web of Science, Cochrane library, and Embase Database up to November 25, 2021. The odds ratio (OR) or relative risk (RR) with 95% confidence intervals (CI) was pooled and a dose-response analysis was performed.

RESULTS

Four studies with 7114 participants for osteoporosis and thirteen studies with 391,956 participants for fracture incidence were included in the meta-analyses. High versus low coffee consumption was associated with a lower risk of osteoporosis [pooled OR (95% CI): 0.79 (0.65-0.92)], while it was non-significantly associated with fracture incidence [pooled OR (95% CI): 0.86 (0.67-1.05) at hip and 0.89 (0.42-1.36) at non-hip]. A non-linear association between the level of coffee consumption and hip fracture incidence was shown (P = 0.004). The pooled RR (95% CI) of hip fracture risk in those who consumed 1, 2-3, 4, and ≥ 9 cups of coffee per day was 0.92 (0.87-0.97), 0.89 (0.83-0.95), 0.91 (0.85-0.98), and 1.10 (0.76-1.59), respectively. The significance in the association between coffee consumption and the hip fracture incidence decreased in those studies that had larger sample size, higher quality, and more adjustments.

CONCLUSIONS

A dose-dependent relationship may exist between coffee consumption and hip fracture incidence. The effect of high versus low coffee consumption was influenced by study designs. Further studies with dedicated designs are needed to confirm the independent effects of coffee consumption on bone health.

Impacts of polyphenols on laying hens' productivity and egg quality: A review

There has been a rapid increase in the world's output of main poultry products (meat and eggs). This reflects customer desire for these high-quality and safe products and the comparatively low price. Recently, natural feed additives, plants and products have been increasingly popular in the poultry and livestock industries to maintain and improve their health and production. Polyphenols are a type of micronutrient that is plentiful in our diet. They are phytochemicals that have health benefits, notably cardiovascular, cognitive function, antioxidant, anti-mutagenic, anti-inflammatory, antistress, anti-tumour, anti-pathogen, detoxification, growth-promoting and immunomodulating activities. On the other hand, excessive polyphenol levels have an unclear and sometimes negative impact on gastrointestinal tract health, nutrient digestion, digestive enzyme activity, vitamin, mineral absorption, laying hens performance and egg quality. As a result, this review illuminated polyphenols' various sources, classifications, biological activities, potential usage restrictions and effects on poultry, layer productivity and egg external and internal quality.

Assessing the Association between Important Dietary Habits and Osteoporosis: A Genetic Correlation and Two-Sample Mendelian Randomization Study

Objective: Osteoporosis (OP) is the most common bone disease. The genetic and metabolic factors play important roles in OP development. However, the genetic basis of OP is still elusive. The study aimed to explore the relationships between OP and dietary habits. Methods: This study used large-scale genome-wide association study (GWAS) summary statistics from the UK Biobank to explore potential associations between OP and 143 dietary habits. The GWAS summary data of OP included 9434 self-reported OP cases and 444,941 controls, and the GWAS summary data of the dietary habits included 455,146 participants of European ancestry. Linkage disequilibrium score regression (LDSC) was used to detect the genetic correlations between OP and each of the 143 dietary habits, followed by Mendelian randomization (MR) analysis to further assess the causal relationship between OP and candidate dietary habits identified by LDSC. Results: The LDSC analysis identified seven candidate dietary habits that showed genetic associations with OP including cereal type such as biscuit cereal (coefficient = −0.1693, p value = 0.0183), servings of raw vegetables per day (coefficient = 0.0837, p value = 0.0379), and spirits measured per month (coefficient = 0.115, p value = 0.0353). MR analysis found that OP and PC17 (butter) (odds ratio [OR] = 0.974, 95% confidence interval [CI] = (0.973, 0.976), p value = 0.000970), PC35 (decaffeinated coffee) (OR = 0.985, 95% CI = (0.983, 0.987), p value = 0.00126), PC36 (overall processed meat intake) (OR = 1.035, 95% CI = (1.033, 1.037), p value = 0.000976), PC39 (spirits measured per month) (OR = 1.014, 95% CI = (1.011, 1.015), p value = 0.00153), and servings of raw vegetables per day (OR = 0.978, 95% CI = (0.977, 0.979), p value = 0.000563) were clearly causal. Conclusions: Our findings provide new clues for understanding the genetic mechanisms of OP, which focus on the possible role of dietary habits in OP pathogenesis.

The effects of caffeine on bone mineral density and fracture risk

Caffeine is a regular part of the diet of many adults (coffee, tea, soft drinks, and energy drinks). Multiple molecular effects of caffeine suggest that it may promote bone loss. Given the extensive consumption of caffeine worldwide, any impact of caffeine consumption on bone strength and/or density would have large population health implications. The most well-established pharmacological effect of caffeine is non-specific antagonism of adenosine receptors. Adenosine regulates bone metabolism in a complex manner, with in vitro studies suggesting that direct stimulation of adenosine A_2A and A_2B receptors induces bone formation by activating osteoblasts and suppressing osteoclast differentiation and function. Thus, competitive inhibition of adenosine A₂ receptors by caffeine may inhibit bone formation and promote bone resorption. However, antagonism of adenosine A₁ receptors may have opposing effects. Caffeine has also been suggested to affect bone through derangement of calcium metabolism, alteration of vitamin D responses, and other mechanisms. In clinical and population-based studies, the impact of caffeine consumption on bone metabolism offers a mixed picture, with some but not all studies suggesting a potential link between caffeine intake and reduced bone mineral density or increased fracture risk. Differences in methodology, selected populations, and duration/timing of the studies may account for study outcome discrepancies. The in vitro effects of caffeine on cells involved in bone metabolism suggest that caffeine intake may promote osteoporosis, and some but not all clinical studies support a modest adverse caffeine impact. Herein, we describe the basic biology of caffeine as it pertains to bone, review the clinical literature to date, and consider the implications of the current data on clinical practice and future studies.

Coffee consumption and caffeine intake in relation to risk of fractures: a systematic review and dose-response meta-analysis of observational studies

BACKGROUND

Conflicting reports are available about the association of coffee or caffeine intake and risk of fracture. We performed the current updated systematic review and dose-response meta-analysis of coffee consumption and caffeine intake and risk of fracture to quantify this association.

MATERIALS AND METHODS

PubMed/Medline, ISI Web of Science, and Scopus, Cochrane database were searched up to July 2021. Random-effects model or fixed-effects model was used to pool the study-specific effect sizes (ESs) and 95% confidence intervals (CIs). Dose-response relationship was examined using linear and non-linear dose-response analyses. The certainty of evidence was assessed using NutriGrade tool.

RESULTS

Out of 22 eligible studies included in the meta-analysis, 15 had cohort and 7 had case-control design. We found no significant association between coffee consumption and risk of fracture, either based on pooling cohort (RR: 0.99; 95% CI: 0.88, 1.12; I2 = 71.4%, Pheterogeneity < 0.01) or case-control studies (OR: 1.13; 95% CI: 0.87, 1.46; I2 = 49.0%, Pheterogeneity=0.08). In the subgroup analysis of cohort studies, we observed that higher coffee intake was inversely associated with risk of fracture in men (RR: 0.85; 95% CI: 0.76 to 0.94). In addition, a positive association was seen between coffee consumption and risk of fracture in studies with less than 12 years of follow-up (RR: 1.14; 95% CI: 1.02 to 1.27). With regard to caffeine intake, a statistically significant positive association was seen with risk of fracture (RR: 1.15; 95% CI, 1.08 to 1.23; I2=26.6%, n = 8). In the dose-response analysis, we found that each additional 100 mg caffeine intake was marginally associated with 2% greater risk of fracture (RR: 1.02; 95% CI: 1 to 1.05; I2= 70.3%, n = 6).

CONCLUSION

High coffee consumption was protectively associated with risk of fracture in men, while caffeine intake was positive associated with risk.

Nutrition, Physical Activity, and Dietary Supplementation to Prevent Bone Mineral Density Loss: A Food Pyramid

Bone is a nutritionally modulated tissue. Given this background, aim of this review is to evaluate the latest data regarding ideal dietary approach in order to reduce bone mineral density loss and to construct a food pyramid that allows osteopenia/osteoporosis patients to easily figure out what to eat. The pyramid shows that carbohydrates should be consumed every day (3 portions of whole grains), together with fruits and vegetables (5 portions; orange-colored fruits and vegetables and green leafy vegetables are to be preferred), light yogurt (125 mL), skim milk (200 mL,) extra virgin olive oil (almost 20 mg/day), and calcium water (almost 1 l/day); weekly portions should include fish (4 portions), white meat (3 portions), legumes (2 portions), eggs (2 portions), cheeses (2 portions), and red or processed meats (once/week). At the top of the pyramid, there are two pennants: one green means that osteopenia/osteoporosis subjects need some personalized supplementation (if daily requirements cannot be satisfied through diet, calcium, vitamin D, boron, omega 3, and isoflavones supplementation could be an effective strategy with a great benefit/cost ratio), and one red means that there are some foods that are banned (salt, sugar, inorganic phosphate additives). Finally, three to four times per week of 30-40 min of aerobic and resistance exercises must be performed.

Modifiable lifestyle factors associated with fragility hip fracture: a systematic review and meta-analysis

INTRODUCTION

Among the various hip fracture predictors explored to date, modifiable risk factors warrant special consideration, since they present promising targets for preventative measures. This systematic review and meta-analysis aims to assess various modifiable risk factors.

MATERIAL AND METHODS

We searched four online databases in September 2017. We included studies that reported on modifiable lifestyle risk factors for sustaining fragility hip fractures. The quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS). The inclusion criteria consisted of (1) adult patients with osteoporotic hip fracture, (2) original study, (3) availability of full text articles in English, and (4) report of a modifiable lifestyle risk factor.

RESULTS

Thirty-five studies, containing 1,508,366 subjects in total, were included in this study. The modifiable risk factors that were significantly associated with an increased risk of hip fracture were the following: weight < 58 kg (128 lbs) (pooled OR 4.01, 95% CI 1.62-9.90), underweight body mass index (BMI) (< 18.5) (pooled OR 2.83, 95% CI 1.82-4.39), consumption of ≥ 3 cups of coffee daily (pooled OR 2.27, 95% CI 1.04-4.97), inactivity (pooled OR 2.14, 95% CI 1.21-3.77), weight loss (pooled OR 1.88, 95% CI 1.32-2.68), consumption of ≥ 27 g (approx. > 2 standard drinks) alcohol per day (pooled OR 1.54, 95% CI 1.12-2.13), and being a current smoker (pooled OR 1.50, 95% CI 1.22-1.85). Conversely, two factors were significantly associated with a decreased risk of hip fracture: obese BMI (> 30) (pooled OR 0.58, 95% CI 0.34-0.99) and habitual tea drinking (pooled OR 0.72, 95% CI 0.66-0.80).

CONCLUSION

Modifiable factors may be utilized clinically to provide more effective lifestyle interventions for at risk populations. We found that low weight and underweight BMI carried the highest risk, followed by high coffee consumption, inactivity, weight loss, and high daily alcohol consumption.

The effect of high-dose, short-term caffeine intake on the renal clearance of calcium, sodium and creatinine in healthy adults

The consumption of caffeine has been linked to osteoporosis, believed to be due to enhanced bone resorption as a result of increased calcium excretion in the urine. However, the amount of calcium in the urine may not necessarily reflect the true effect of caffeine on calcium clearance. This study therefore examined the impact of high-dose, short-term caffeine intake on renal clearance of calcium, sodium and creatinine in healthy adults. In a double-blind clinical study, participants chewed caffeine (n = 12) or placebo (n = 12) gum for 5 minutes at 2-hour intervals over a 6-hour treatment period (800 mg total caffeine). Caffeine increased renal calcium clearance by 77%. Furthermore, the effect was positively correlated with sodium clearance and urine volume, suggesting that caffeine may act through inhibition of sodium reabsorption in the proximal convoluted tubule. This study confirmed that caffeine does increase renal calcium clearance and fosters further investigation into safe consumption of caffeine.

The Association between Tea Consumption and the Risk of Fracture: A Dose-Response Meta-Analysis of Prospective Cohort Studies

OBJECTIVES

Inconsistent results exist on the role of tea consumption on subsequent risk of fracture. A dose-response meta-analysis was therefore conducted to assess the association of tea consumption with the risk of fracture based on prospective cohort studies.

METHODS

The electronic databases of PubMed, Embase, and the Cochrane library were systematically searched to identify prospective cohort studies from inception until September 2020. The categories of high versus low and dose-response meta-analyses for tea consumption on the risk of fracture were calculated using the random-effects model. Eight prospective cohort studies recruited 774,134 individuals selected for the final meta-analysis.

RESULTS

An increment of 1 cup in tea consumption was not associated with the risk of fracture [relative risk (RR), 0.98; 95% confidence interval (CI), 0.96-1.00; P = 0.102]. Moreover, the highest tea consumption category was associated with a reduced risk of fracture (RR, 0.93; 95% CI, 0.88-0.98; P = 0.005). Furthermore, heavy (RR, 0.91; 95% CI, 0.85-0.98; P = 0.008) and mild (RR, 0.97; 95% CI, 0.94-1.00; P = 0.046) tea consumption were associated with lower risk of fracture. However, moderate tea consumption was not associated with the risk of fracture (RR, 0.98; 95% CI, 0.94-1.02; P = 0.281).

CONCLUSION

This study found that increased tea consumption may provide a protective role in the risk of fracture. The benefits of tea consumption should be further explored according to the characteristics of the individuals.

Alcohol Consumption Moderated the Association Between Levels of High Blood Lead or Total Urinary Arsenic and Bone Loss

Metal exposure and lifestyle are important risk factors for osteoporosis. Our study aimed to investigate the association between red blood cell lead and cadmium, total urinary arsenic, and plasma selenium levels and bone mineral density (BMD). In addition, we explored whether alcohol and coffee consumption modified the association between BMD and metals and metalloids. In total, 437 participants who underwent adult or senile physical examinations were recruited. Bone loss was defined as a calcaneus BMD T-score of <-1. Blood cadmium and lead and plasma selenium levels were measured using inductively coupled plasma mass spectrometry. Levels of urinary arsenic species were determined using high-performance liquid chromatography-hydride generator-atomic absorption spectrometry. The total urinary arsenic level was defined as the sum of the levels of urinary arsenic species. The BMD T-scores decreased significantly with increasing blood lead levels. The BMD T-scores also showed a downward trend with increasing total urinary arsenic levels. The odds ratio (OR) and 95% confidence interval (CI) for bone loss in patients with blood lead levels >57.58 versus 35.74 μg/dL were 1.98 and 1.17-3.34. In addition, the greater the lead or arsenic exposure and alcohol intake was the higher the OR for bone loss with multivariate ORs of 2.57 (95% CI 1.45-4.56) and 2.96 (95% CI 1.67-5.22), respectively. To the best of our knowledge, this study is the first to demonstrate that high total urinary arsenic or blood lead levels and frequent or occasional alcohol consumption had a significant multiplicative interaction for increasing the OR for bone loss.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS/AMERICAN COLLEGE OF ENDOCRINOLOGY CLINICAL PRACTICE GUIDELINES FOR THE DIAGNOSIS AND TREATMENT OF POSTMENOPAUSAL OSTEOPOROSIS-2020 UPDATE

Objective: The development of these guidelines is sponsored by the American Association of Clinical Endocrinologists (AACE) Board of Directors and American College of Endocrinology (ACE) Board of Trustees and adheres with published AACE protocols for the standardized production of clinical practice guidelines (CPGs). Methods: Recommendations are based on diligent reviews of the clinical evidence with transparent incorporation of subjective factors, according to established AACE/ACE guidelines for guidelines protocols. Results: The Executive Summary of this 2020 updated guideline contains 52 recommendations: 21 Grade A (40%), 24 Grade B (46%), 7 Grade C (14%), and no Grade D (0%). These detailed, evidence-based recommendations allow for nuance-based clinical decision-making that addresses multiple aspects of real-world care of patients. The evidence base presented in the subsequent Appendix provides relevant supporting information for the Executive Summary recommendations. This update contains 368 citations: 123 (33.5%) evidence level (EL) 1 (highest), 132 (36%) EL 2 (intermediate), 20 (5.5%) EL 3 (weak), and 93 (25%) EL 4 (lowest). New or updated topics in this CPG include: clarification of the diagnosis of osteoporosis, stratification of the patient according to high-risk and very-high-risk features, a new dual-action therapy option, and transitions from therapeutic options. Conclusion: This guideline is a practical tool for endocrinologists, physicians in general, regulatory bodies, health-related organizations, and interested laypersons regarding the diagnosis, evaluation, and treatment of post-menopausal osteoporosis. Abbreviations: 25(OH)D = 25-hydroxyvitamin D; AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; AFF = atypical femoral fracture; ASBMR = American Society for Bone and Mineral Research; BEL = best evidence level; BMD = bone mineral density; BTM = bone turnover marker; CI = confidence interval; CPG = clinical practice guideline; CTX = C-terminal telopeptide type-I collagen; DXA = dual-energy X-ray absorptiometry; EL = evidence level; FDA = U.S. Food and Drug Administration; FRAX® = Fracture Risk Assessment Tool; GI = gastrointestinal; HORIZON = Health Outcomes and Reduced Incidence with Zoledronic acid ONce yearly Pivotal Fracture Trial (zoledronic acid and zoledronate are equivalent terms); ISCD = International Society for Clinical Densitometry; IU = international units; IV = intravenous; LSC = least significant change; NOF = National Osteoporosis Foundation; ONJ = osteonecrosis of the jaw; PINP = serum amino-terminal propeptide of type-I collagen; PTH = parathyroid hormone; R = recommendation; ROI = region of interest; RR = relative risk; SD = standard deviation; TBS = trabecular bone score; VFA = vertebral fracture assessment; WHO = World Health Organization.

Sleep Restriction With Circadian Disruption Negatively Alter Bone Turnover Markers in Women

PURPOSE

The purpose of this work is to determine whether an uncoupling of bone turnover markers (BTMs) occurs in women exposed to the combination of sleep restriction with circadian disruption (SRCD), as previously reported in men.

METHODS

Four bone biomarkers (N-terminal propeptide of type I procollagen [P1NP] and osteocalcin = bone formation; C-telopeptide [CTX] = bone resorption; sclerostin = bone formation inhibitor) were measured in bihourly samples over 24 hours at baseline and after approximately 3 weeks of sleep restriction (~5.6 hours of sleep/24 hours) with concurrent circadian disruption (SRCD, recurring 28-hour "day" in dim light). Maximum likelihood estimation in a repeated-measures model was used to assess the effects of SRCD and age on bone biomarkers.

RESULTS

Five women were young (22 ± 2.8 years) and four were older (58 ± 1.8 years). Baseline bone biomarker levels did not differ by age (all P ≥ .07). Bone formation markers were lower after SRCD (estimate ± SEE, ΔP1NP = -9.5 ± 2.8 μg/L, P = .01; Δosteocalcin = -2.3 ± 0.9 ng/mL, P = .04). The P1NP decline was greater in young women (ΔP1NP = -12.9 ± 3.7 μg/L, P = .01). After SRCD, CTX was significantly higher in young women (0.182 ± 0.069 ng/mL, P = .04) but did not change in older women.

CONCLUSIONS

These pilot data are similar to previous findings in men and suggest that SRCD negatively altered bone metabolism in women by decreasing markers of bone formation and, in young women, increasing a marker of bone resorption. If sustained, this pattern of BTM uncoupling may lead to bone loss and lower bone mineral density.

Oolong tea drinking boosts calcaneus bone mineral density in postmenopausal women: a population-based study in southern China

INTRODUCTION

Observational studies have shown that tea consumption has a potentially beneficial effect on bone health. However, few studies have assessed the effects of types of tea consumed on bone health. We aimed to investigate whether drinking oolong tea is associated with increased calcaneus bone mineral density (BMD) in postmenopausal women.

METHODS

From an epidemiological survey in Shantou, 476 postmenopausal women aged 40 to 88 years were enrolled in the study. All women were questioned about their demographic features, lifestyle, health status, types of tea consumed, habit of tea consumption, and habitual dietary intake by use of a structured questionnaire. Estimated areal BMD was measured by calcaneal quantitative ultrasound (QUS).

RESULTS

As compared with non-tea drinkers, oolong tea drinkers had higher calcaneus BMD (β 34.70 [95% CI 10.38, 59.03]). In addition, calcaneus BMD was significantly increased for those drinking 1-5 cups/day (β 27.43 [95% CI 3.70, 51.16]) but not > 5 cups/day. We observed no linear increase in calcaneus BMD with increasing years of tea consumption and local polynomial regression fitting showed a parabola-shaped association between years of tea consumption and calcaneus BMD. However, symptoms of osteoporosis did not differ by types of tea consumed.

CONCLUSION

Long-term moderate oolong tea consumption may have beneficial effects on bone health in postmenopausal women in Shantou of southern China.

Changes in Bone Mineral Density in Women With Breast Cancer: A Prospective Cohort Study

BACKGROUND

Cancer treatment-induced bone loss is an important long-term effect among breast cancer survivors. Little is known, however, about the pattern of bone loss and the factors associated with it.

OBJECTIVE

The aim of this study was to examine annual bone health changes and factors associated with bone loss for 3 years after diagnosis among women with breast cancer.

METHODS

Ninety-nine newly diagnosed women with breast cancer (mean age, 51.1 years) were enrolled in a prospective longitudinal study. Bone mineral density (BMD) was measured with dual-energy x-ray absorptiometry at baseline and yearly for 3 years.

RESULTS

During the 3-year follow-up, the proportion of women who had osteopenia or osteoporosis increased from 33.3% to 62.5%. The BMD of the participants significantly decreased 6.8% in the lumbar spine, 4.6% in the femur neck, and 3.5% in the total hip, with bone loss the greatest in the first year. In multiple linear regression analysis, chemotherapy was significantly associated with bone loss at all sites, and premenopausal status at diagnosis was significantly related to bone loss at the lumbar spine. We found no significant relationship between health behavior status and BMD change at any site.

CONCLUSION

Women newly diagnosed with breast cancer can lose up to 6.8% of BMD during a 3-year follow-up. Chemotherapy and premenopausal status are important risk factors for bone loss.

IMPLICATIONS FOR PRACTICE

Identification of premenopausal women at diagnosis and monitoring BMD before and after chemotherapy are key for promoting bone health in women with breast cancer.

High Consumption of Soft Drinks Is Associated with an Increased Risk of Fracture: A 7-Year Follow-Up Study

(1) Background: Fracture causes a substantial burden to society globally. Some studies have found that soft drinks consumption was associated with the risk of fractures. We aimed to assess the association in the Chinese population; (2) Methods: Data from 17,383 adults aged 20 to 75 years old attending the China Health and Nutrition Survey (CHNS) between 2004 and 2011 were analyzed. Soft drinks consumption and fracture occurrence were self-reported. The cross-sectional and longitudinal associations between soft drink and fracture was assessed using multivariable mixed-effect logistic regression and Cox regression; (3) Results: After adjusting for sociodemographic and lifestyle factors and dietary patterns, compared with those who did not consume soft drinks, participants with daily consumption of soft drinks had an odds ratio (95%CI) of 2.72 (95%CI: 1.45-5.09) for fracture. During a mean 5-year follow-up, there were 569 incident fracture cases. Compared with non-consumers, those with daily soft drinks consumption had a hazard ratio (95%CI) of 4.69 (95%CI: 2.80-7.88) for incident fracture; (4) Conclusions: Soft drinks consumption is directly associated with the risk of fracture. Reducing soft drinks consumption should be considered as an important strategy for individual and population levels to maintain bone health.

History, epidemiology and prevalence of neonatal bone mineral metabolic disorders

The evolutionary patterns of human migration and historical pre/post-industrial revolution have changed the face of bone metabolic disease through past centuries. Cultural, religious, and lifestyle practices continue to alter nutritional recommendations for this expanding diagnosis. Likewise, modern advancements in the field of neonatology and, more specifically, aggressive nutritional management of premature infants have shaped the epidemiology of neonatal bone metabolism over the past two decades. Decreased use of long-term parenteral nutrition, early fortification of enteral nutrition, and stringent American Academy of Pediatrics (AAP) practice guidelines instituting early supplementation of vitamin D have attributed to improved bone mineralization outcomes in both term and preterm infants. Nevertheless, neonatal bone mineral metabolic disorders remain prevalent. In this review, we provide an in-depth look at the diagnoses, therapeutics, and subset populations-both genetic and non-genetic-affected by neonatal bone mineral metabolic disorders.

The Effect of Caffeine on Calcitriol-Inducible Vitamin D Receptor-Controlled Gene Expression in Intestinal and Osteoblastic Cells

Some epidemiological studies suggested caffeine consumption as the cause for bone mineral density loss. Certain genes involved in this process are regulated by vitamin D receptor (VDR). Therefore, we investigated if caffeine can affect inducible expression of VDR-regulated genes, some of them being involved in bone mineralization process. By employing reporter gene assay, polymerase chain reaction, and western blotting, we monitored the VDR activity and expression in cell cultures of intestinal (LS180), osteosarcoma (HOS), and normal human osteoblasts in vitro. While caffeine stimulated calcitriol-inducible VDR-dependent nanoluciferase activity in stable reporter cell line IZ-VDRE (derived from LS180), it rather modulated mRNA levels of target genes, like CYP24A1, BGLAP, SPP1, and TNSF11 in LS180 and HOS cells. However, caffeine significantly decreased calcitriol-inducible CYP24A1, TNSF11, and SPP1 transcripts in osteoblasts. This decrease had non-linear U-shaped profile. Our in vitro data demonstrate biphasic action of caffeine on the expression of certain calcitriol-inducible VDR-regulated genes in normal human osteoblasts.

Nonpharmacological interventions for osteoporosis treatment: Systematic review of clinical practice guidelines

Objectives

The aim of this study was to perform a systematic review of clinical practice guidelines to identify nonpharmacologic recommendations for osteoporosis treatment.

Methods

A systematic review of literature following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses)-statement methodology for clinical practice guidelines was conducted; PROSPERO CRD42019138548. Assessment of selected clinical practice guidelines with the AGREE (Appraisal of Guidelines for Research & Evaluation)-II methodological quality instrument was performed, and those graded over 60 points were selected for recommendations extraction and evidence analysis.

Results

Only 6 clinical practice guidelines fulfilled criteria, 69 nonpharmacological recommendations were extracted: 13 from American Association of Clinical Endocrinologists and American College of Endocrinology guideline, 16 from Malaysian Osteoporosis Society guideline, 15 from the Ministry of Health in Mexico guideline, 14 from Royal Australian College of General Practitioners guideline, 7 from Sociedad Española de Investigación Ósea y del Metabolismo Mineral guideline, and 7 from National Osteoporosis Guideline Group guideline. Percentage by theme showed that the highest number of recommendations were 12 (17.1%) for vitamin D, 11 (15.7%) for a combination of calcium and vitamin D, and 11 (15.7%) for exercise.

Conclusions

These recommendations address integrating interventions to modify lifestyle, mainly calcium and vitamin D intake, and exercise. Other recommendations include maintaining adequate protein intake, identification and treatment of risk factors for falls, and limiting the consumption of coffee, alcohol and tobacco. Considerations on prescription must be taken.

Tea consumption and risk of fractures: an updated meta-analysis

This meta-analysis included 16 studies, involving seven cohort studies and nine case-control studies, and the results indicated that tea consumption may be associated with a reduced the risk of fractures.

INTRODUCTION

Regarding relationship of tea consumption with the risk of fractures remains controversial. We performed a meta-analysis to elucidate the association between tea consumption and the risk of fractures.

METHODS

Relevant articles were identified up to March 2019 by searching PubMed, Web of Science, and Embase databases. The pooled relative risks (RRs) with 95% confidence intervals (CIs) were computed utilizing fixed or random effects model based on heterogeneity.

RESULTS

Altogether 16 studies (seven cohort and nine case-control studies) were included in this meta-analysis, involving 772,707 participants with 37,166 fracture cases. The RRs (95% CIs) of fracture for the highest versus lowest category of tea consumption were 0.86 (0.78-0.94). Subgroup analysis indicated significant associations in cohort studies (0.90 (0.86-0.94)) and case-control studies (0.77 (0.69-0.85)).

CONCLUSIONS

The current meta-analysis indicates that tea consumption may be associated with a reduced the risk of fractures.

Changes in calcium metabolism and bone mineral density in new users of medroxyprogesterone acetate during the first year of use

OBJECTIVE

To evaluate calcium metabolism and bone mineral density (BMD) in new users of depot medroxyprogesterone acetate (DMPA) in the first year of use.

METHODS

This prospective, non-randomized study, conducted at the University of Campinas, São Paulo, Brazil, was carried out between February 2011 and February 2013. Women aged from 18 to 40 with a body mass index (BMI, calculated as weight in kilograms divided by the square of height in meters) <30 and with no known history of disease or medication use who chose to use DMPA were paired by age (±1 year) and BMI (±1) with women commencing the use of a copper intrauterine device (IUD). The primary outcomes were BMD measured by dual-energy X-ray absorptiometry and calcium metabolism markers; other variables were body composition and lifestyle habits. Repeated measures analysis of variance (ANOVA) and multiple regression analyses were used to evaluate associations.

RESULTS

Twenty-seven women using DMPA and 24 using IUD were evaluated, with a mean age of 29.7 years and 28.6 years, respectively. The DMPA group presented with a 3.6% (P<0.001) loss of lumbar spine BMD, a 2.1% (P=0.100) loss of femoral neck BMD and higher phosphorus (P=0.014) concentrations at 12 months compared to the IUD group. The decreases in BMD were associated with the use of DMPA, while total mass and coffee intake were found to be protective factors.

CONCLUSION

Changes in calcium metabolism and a decrease in BMD were found in the DMPA group at 12 months.

Caffeine Consumption through Coffee: Content in the Beverage, Metabolism, Health Benefits and Risks

Caffeine (1,3,7-trimethylxanthine) is the most consumed psychoactive substance in the world, acting by means of antagonism to adenosine receptors, mainly A1 and A2A. Coffee is the main natural source of the alkaloid which is quite soluble and well extracted during the brew’s preparation. After consumption, caffeine is almost completely absorbed and extensively metabolized in the liver by phase I (cytochrome P450) enzymes, mainly CYP1A2, which appears to be polymorphically distributed in human populations. Paraxanthine is the major caffeine metabolite in plasma, while methylated xanthines and methyluric acids are the main metabolites excreted in urine. In addition to stimulating the central nervous system, caffeine exerts positive effects in the body, often in association with other substances, contributing to prevention of several chronic diseases. The potential adverse effects of caffeine have also been extensively studied in animal species and in humans. These aspects will be approached in the present review.

Prematurity Does Not Increase Early Childhood Fracture Risk

OBJECTIVE

To evaluate the impact of prematurity on fracture by age 5, controlling for medications and comorbidities of prematurity.

STUDY DESIGN

We performed a retrospective cohort study of infants born in Military Treatment Facilities in 2009-2010 with ≥5 years of follow-up care. Gestational age, low birth weight, comorbidities of prematurity (osteopenia, necrotizing enterocolitis, chronic lung disease, and cholestasis) and fractures were identified by International Classification of Disease, 9th Edition, codes. Pharmaceutical records identified treatment with caffeine, diuretics, postnatal corticosteroids, and antacids. Poisson regression analysis determined fracture rate by 5 years of life.

RESULTS

There were 65 938 infants born in 2009-2010 who received care in the military health system for ≥5 years, including 3589 born preterm; 165 born at ≤28^6/7 weeks of gestation, 380 born at 29-31^6/7 weeks of gestation, and 3044 born at 32-36^6/7 weeks of gestation. Preterm birth at any gestational age was not associated with fracture rate in adjusted models. The fracture rate was increased with cholestasis, proton pump inhibitor exposure, and male sex.

CONCLUSIONS

Prematurity was not associated with fracture rate. Neonatal cholestasis and proton pump inhibitor treatment were associated with increased fractures by age 5.

The Impact of Socioeconomic Characteristics and Lifestyles on Vitamin D Deficit in Mentally Ill Patients

Mental illnesses put patients at high risk for vitamin D deficit. The aim of the research is to examine the impacts of socioeconomic characteristics and lifestyles on vitamin D deficiency in mentally diseased patients. In this crosssectional study we used blood samples from patients who were treated for mental disorders at Specialist-consultative unit of the Health Center and Clinical Center Kragujevac from May-June 2014. The study used a questionnaire for the assessment of vitamin D status. The study included 220 subjects with different types of mental disorders. Normal values of vitamin D were detected in 16% of patients whereas 64% of patients had vitamin D deficiency. The patients with vitamin D deficit were in average 3 years older than that but the difference is not statistically significant (p>0.05). The patients with vitamin D deficiency were primarily female (p=0.003), people with high-school education from urban environment who lived in bad life conditions (p>0.05). Between patients with and without vitamin D deficiency there is no difference in cigarette consumption, in the number of cigarettes per day, in alcohol usage, in coffee consumption and in nutrition. However, the patients without vitamin D deficiency spent more time outside; during the past year were more exposed to sun and during the past seven days spent more than 30 minutes a day exposed to sunlight (p<0.01). These facts indicate that there is a current need for further research in this area.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY CLINICAL PRACTICE GUIDELINES FOR THE DIAGNOSIS AND TREATMENT OF POSTMENOPAUSAL OSTEOPOROSIS - 2016

ABBREVIATIONS

AACE = American Association of Clinical Endocrinologists AFF = atypical femur fracture ASBMR = American Society for Bone and Mineral Research BEL = best evidence level BMD = bone mineral density BTM = bone turnover marker CBC = complete blood count CI = confidence interval DXA = dual-energy X-ray absorptiometry EL = evidence level FDA = U.S. Food and Drug Administration FLEX = Fracture Intervention Trial (FIT) Long-term Extension FRAX_® = Fracture Risk Assessment Tool GFR = glomerular filtration rate GI = gastrointestinal HORIZON = Health Outcomes and Reduced Incidence with Zoledronic Acid Once Yearly IOF = International Osteoporosis Foundation ISCD = International Society for Clinical Densitometry IU = international units IV = intravenous LSC = least significant change NBHA = National Bone Health Alliance NOF = National Osteoporosis Foundation 25(OH)D = 25-hydroxy vitamin D ONJ = osteonecrosis of the jaw PINP = serum carboxy-terminal propeptide of type I collagen PTH = parathyroid hormone R = recommendation RANK = receptor activator of nuclear factor kappa-B RANKL = receptor activator of nuclear factor kappa-B ligand RCT = randomized controlled trial RR = relative risk S-CTX = serum C-terminal telopeptide SQ = subcutaneous VFA = vertebral fracture assessment WHO = World Health Organization.

Lack of Influence of Thyroid Hormone on Bone Mineral Density and Body Composition in Healthy Euthyroid Women

Objective: The objective of this study was to evaluate whether evolution of bone mineral density (BMD) is associated with the thyroid hormone profile in a cohort of euthyroid women with no other known diseases within 1 year. Methods: This was a prospective cohort study conducted at the University of Campinas, Brazil. We used a database with 52 women aged 20-39 who were followed for 1 year in a family planning outpatient clinic. The inclusion criteria were body mass index (BMI) <30 kg/m², no known diseases/medication use, fasting glucose <100 mg/dl, and 2 h glucose after a 75 g oral glucose load <140 mg/dl. The women were divided into groups of normal weight (n = 30) and overweight (n = 22). The main outcomes were BMD measured by dual-energy x-ray absorptiometry (DXA) and thyroid hormone profile (thyrotropin TSH, free triiodothyronine FT3, free thyroxine FT4, and T3/T4 ratio); other variables were body composition (DXA), calcium metabolism markers, and life habits. We used a repeated measures analysis of variance (ANOVA) and multiple regression analyses to evaluate associations. Results: At the baseline data collection, overweight women showed a higher T3/T4 ratio, leptin, calcium, BMD in the lumbar spine and total femur, total mass, mass, and percentage of fat mass than normal weight women. At 12 months, both groups had increased FT4, calcium, ALP, femoral neck BMD, and total mass by time effect. The normal weight group presented a decrease of vitamin D when compared to the baseline. Increased BMD of the femoral neck was associated with moderate coffee intake, and as such, there were no associations found between this increase and the thyroid hormone profile. Leptin and ALP were associated with total mass variation, while leptin and PTH were associated with fat mass variation. The normal BMI was inversely associated with the variation of total mass, mass, and percentage of fat mass, and engaging in regular physical activity was inversely associated with fat mass variation. Conclusions: In this sample of euthyroid healthy women who were both normal weight and overweight, the thyroid hormone profile was not associated with variations in bone mineral density and body composition after a 1 year follow-up.

Health Related Nutritional Knowledge and Dietary Behavior Regarding Caffeine Intake among High School Students in Yongin Region

Objectives

We aimed to examine health-related nutritional knowledge and dietary behavior related to caffeine intake among high school students (n = 310) in the Yongin region of Korea.

Methods

Data were collected using a face-to-face survey, and analyzed using chi-square test, t- test, and logistic regression analysis.

Results

The level of caffeine intake in respondents was divided into low (< 30 mg/d; n = 208) and high caffeine intake groups (> 30 mg/d; n = 102). Total nutritional knowledge related to bone disease was higher in the low intake group (score 2.75) than the high intake group (score 2.39; p < 0.05). The high intake group had lower scores for nutritional knowledge (score 0.70; p < 0.05) related to how caffeinated beverages affect sleep and for dietary behavior (score 3.25; p < 0.001), based on “I avoid caffeinated foods before sleep,” than the low intake group (nutritional knowledge score, 0.80; dietary behavior score, 3.76).

Conclusion

In the overall analysis, the low caffeine intake group had better nutritional knowledge related to bone and sleep health, and healthier dietary behavior related to sleep health compared with the high intake group.

Does coffee drinking have beneficial effects on bone health of Taiwanese adults? A longitudinal study

Background

Results from studies investigating the association between coffee consumption and osteoporosis or bone mineral density (BMD) have been inconsistent. This longitudinal study was performed to assess the effect of coffee drinking on bone health of Taiwanese adults.

Methods

Data were retrieved from the Li-Shin (Landseed) Hospital in Taoyuan City. In 2006, 6152 participants completed a questionnaire on coffee drinking and other lifestyle factors. In 2014, 5077 of them were followed up. Nonetheless, a total of 2395 participants with incomplete data were excluded. The final analyses included 2682 participants comprising 1195 men and 1487 women (706 premenopausal and 781 postmenopausal). T-scores were derived from the osteo-sono assessment index (OSI) which is a surrogate of BMD. Coffee drinking was categorized as “no, medium, and high” based on the number of cups that were consumed per week in both 2006 and 2014.

Results

In general, medium and high coffee drinking were associated with higher T-scores. However, significant results were observed only among high drinkers (β = 0.158; P = 0.0038). Nonetheless, the test for linear trend was significant (P = 0.0046). After stratification by sex, medium and high coffee drinking were associated with higher T-scores. However, significant results were prominent only among high male drinkers (β = 0.237; P = 0.0067) and the test for trend was significant (P = 0.0161). Based on menopausal status, coffee drinking was associated with higher T-scores. Nevertheless, significant results were found only among premenopausal women (β = 0.233; P = 0.0355 and β = 0.234; P = 0.0152 for medium and high coffee drinking, respectively. The test for linear trend was significant (P = 0.0108).

Conclusion

Coffee drinking was significantly associated with higher T-scores hence, a lower risk of osteoporosis in men and premenopausal women.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-6168-0) contains supplementary material, which is available to authorized users.

Habitual Tea Consumption and Risk of Fracture in 0.5 Million Chinese Adults: A Prospective Cohort Study

Background: Tea consumption may have favorable effects on risk of fracture. However, little is known about such association in Chinese adults. The aim of this study was to examine the association between tea consumption and risk of hospitalized fracture in Chinese adults. Methods: The present study included 453,625 participants from the China Kadoorie Biobank (CKB). Tea consumption was self-reported at baseline. Hospitalized fractures were ascertained through linkage with local health insurance claim databases. The results: During a median of 10.1 years of follow-up, we documented 12,130 cases of first-time any fracture hospitalizations, including 1376 cases of hip fracture. Compared with never tea consumers, daily tea consumption was associated with lower risk of any fracture (hazard ratio (HR): 0.88; 95% confidence interval (CI): 0.83, 0.93). Statistically significant reduced risk of hip fracture was shown among daily consumers who most commonly drank green tea (HR: 0.80; 95% CI: 0.65, 0.97) and those who had drunk tea for more than 30 years (HR: 0.68; 95% CI: 0.52, 0.87). Our conclusions: Habitual tea consumption was associated with moderately decreased risk of any fracture hospitalizations. Participants with decades of tea consumption and those who preferred green tea were also associated with lower risk of hip fracture.

Hongyacha, a Naturally Caffeine-Free Tea Plant from Fujian, China

Hongyacha (HYC) is a type of new wild tea plant discovered in Fujian Province, China. This tea is helpful to the healing or prevention of disease in its original growing area. However, research on this tea is limited. Our results showed that HYC displayed obvious differences in its morphological characteristics compared with Cocoa tea ( Camellia ptilophylla Chang), a famous caffeine-free tea plant in China. Theobromine and trans-catechins, but not caffeine and cis-catechins, were the dominant purine alkaloids and catechins detected in HYC. HYC might contain abundant gallocatechin-(4 → 8)-gallocatechin gallate, 1,3,4,6-tetra- O-galloyl-β-d-glucopyranose, and (-)-gallocatechin-3,5-di- O-gallate, which were not detected in regular tea. We also found that the TCS1 of HYC was distinct, and the responding recombinant protein exhibited only theobromine synthase activity. The obtained results showed that HYC is a new kind of caffeine-free tea plant and may be used for scientific protection and efficient utilization in the future.

The importance of the circadian system & sleep for bone health

Adequate sleep timed appropriately during the circadian night is important for numerous biological processes and systems. New evidence suggests that both sleep timing and duration may be important for optimal bone health as well. This review examines the diurnal variation of bone turnover markers (BTMs) and the importance of circadian clock genes in regulating bone mass. In addition, this review explores the evidence for a link between shift work (and its associated disturbances in sleep duration/quality and circadian alignment) and alterations in bone metabolism and bone health. Finally, we review how commonly used medications and over-the-counter substances (e.g. caffeine, melatonin) complicate the relationship between sleep and circadian disorders and bone health.

Association between tea consumption and osteoporosis: A meta-analysis

BACKGROUND

Previous reports have suggested a potential association of tea consumption with the risk of osteoporosis. As such association is controversial, we conducted a meta-analysis to assess the relationship between tea consumption and osteoporosis.

METHODS AND FINDINGS

We systematically searched PubMed, EMBASE and WanFang databases until March 30, 2016, using the keywords "tea and osteoporosis," without limits of language. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were derived by using random-effects models throughout the analyses. We conducted the analysis of the statistical heterogeneity using Cochrane I. The funnel plot was used to speculate the publication bias, while the subgroup analysis and multiround elimination method were employed.

RESULTS

Our study was based on 17 journal articles, including 2 prospective cohort studies, 4 case-control studies, and 11 cross-sectional studies. In the present study, the total OR of osteoporosis for the highest versus the lowest categories of tea consumption was 0.62 (95% CI, 0.46-0.83), with significant heterogeneity among studies (I = 94%, P < .01). There was, however, no publication bias of the meta-analysis about tea consumption and osteoporosis. Subgroup analysis showed that tea consumption could reduce the risk of osteoporosis in all examined subgroups.

CONCLUSION

In the present study, it can be concluded from the results that tea consumption can reduce the risk of osteoporosis.