Calcium in Women: Healthy Bones and Much More

Musculoskeletal Failure

Osteoarthritis, osteoporosis, and sarcopenia are prevalent musculoskeletal disorders that significantly impact the aging population's health and quality of life. Osteoarthritis, characterized by joint inflammation, leads to pain, stiffness, and reduced mobility. Osteoporosis, a condition marked by bone density loss, increases fracture susceptibility, especially in postmenopausal women and older adults. Sarcopenia, the age-related loss of muscle mass and function, contributes to frailty and an increased risk of falls. Combined, osteoarthritis, osteoporosis and sarcopenia constitute "Musculoskeletal Failure." These 3 conditions share common risk factors like aging, genetics, and hormonal changes, as well as unhealthy lifestyle behaviors resulting in systemic chronic inflammation. Healthy lifestyle behaviors, including regular physical activity and a nutritious diet across the lifespan play a crucial role in the prevention and management of musculoskeletal failure. Awareness of the relationship between lifestyle behaviors, systemic chronic inflammation and the development and progression of these 3 common conditions is a key step in prevention, early detection and are essential for addressing the complex interplay of these musculoskeletal disorders. As the global population ages, understanding and effectively preventing and managing osteoarthritis, osteoporosis, and sarcopenia become paramount for promoting healthy aging and mitigating the societal and economic burden associated with these conditions.

Healthy eating norms and food consumption

BACKGROUND/OBJECTIVES

Beliefs about what people think they ought to eat to be healthy ('healthy eating norms (HENs)') may be important influences on food consumption. The purpose of this study was to examine the predictive roles of normative expectations and demographics, personal values, substance use behaviours and body weight on reported food consumption among middle-aged Australians.

SUBJECTS/METHODS

A questionnaire was administered by mail to a random sample of people aged 40 years and above, drawn from the Electoral Rolls in Victoria, Australia. Part of the questionnaire contained questions about the respondents' beliefs about what should they eat to be healthy, what actually they ate, their personal values, smoking and alcohol use, as well as self-reported heights and weights and demographic characteristics.

RESULTS

Respondents' reported food consumption did not match their HENs. Demographics, smoking, body mass index (BMI) and personal values, and HENs were associated with reported consumption but the relationships differed among men and women. Generally, high energy-dense, nutrition-poor (EDNP) food consumption was negatively associated with age. Fruit and vegetable HEN and consumption was positively linked to universalist values but negatively related to smoking status among men. In contrast in women, fruit and vegetable HENs were positively related to income and education while EDNP HEN was negatively associated with age and income but positively linked to body weight and power values.

CONCLUSIONS

Reported food consumption was associated with HEN, personal values, demographics, smoking and BMI through different pathways among men and women. The implications for nutrition promotion are discussed.

Bone health: part 1, nutrition

Nutrition, in sufficient amount and substance, is crucial for healthy growth and development of the skeleton and surrounding tissues, especially in physically active populations. Inadequate nutrition has been linked to maladies such as the female athlete triad, as well as poor training or competitive performance and increased risk of injury. Dietary choices favoring items high in quality protein of animal or plant origin, polyunsaturated fatty acids, fruits and vegetables high in potassium and fiber, and dairy products or other beverages fortified with calcium and vitamin D are essential to athletes to ensure adequate vitamin and mineral availability to the skeleton, which in turn can affect peak physical performance.

Sociodemographic variation in knowledge of osteoporosis and locally available calcium-rich foods among urban women living on low incomes in Davao, Philippines

We explored knowledge of osteoporosis and locally available calcium-rich foods among 1,151 urban women in the Philippines and analyzed the cross-sectional associations of their responses to questions about knowledge with their age, educational background, and family income status. In total, 80.3% of the women had heard about osteoporosis; a higher educational background independently predicted this awareness. For knowledge about locally available calcium-rich foods, older age was a positive predictor, whereas higher educational background was a negative predictor. We believe that more emphasis should be placed on locally available foods as part of nutritional education for young urban Filipinos.

Genetic background influences metabolic response to dietary phosphorus restriction

Dietary phosphorus (P) is essential to bone growth and turnover; however, little research has focused on the genetic mechanisms controlling P utilization. Understanding the interactions between genetics and dietary P that optimize bone integrity could provide novel interventions for osteoporosis. Thirty-six pigs from two sire lines known to differ in bone structure [heavier boned (HB) and lighter boned (LB)] were assigned to one of the three diets (P adequate, P repletion or P deficient). After 14 days, bone marrow and intact radial bones were collected. Differences between these lines in growth rate, bone integrity and gene expression within bone marrow were observed. In HB, but not LB, pigs, the P-deficient diet decreased weight gain (P<.01). For both lines, P deficiency caused a reduction in radial bone strength (P<.01), but HB P-deficient animals had greater (P<.10) bone integrity than P-deficient LB pigs. In HB, but not LB, pigs, dietary treatment affected the expression of CALCR (calcitonin receptor) (P<.05), VDR (vitamin D receptor) (P<.04) and IGFBP3 (insulin-like growth factor binding protein 3) (P<.06). There was also a trend of increased IL6 (interleukin-6), TFIIB (transcription initiation factor IIB) and SOX9 (sex determining region Y-box 9) expression with P deficiency in HB, but not LB, pigs. Both genetic backgrounds responded similarly to P deficiency with an increase in the expression of OXTR (oxytocin receptor) and IGF1 (insulin-like growth factor 1). Differences in growth rate, bone integrity and gene expression within the bone marrow suggest a difference in the homeorhetic control of P utilization between these genetic lines. Understanding these differences could lead to novel treatments for osteoporosis and aid in the development of tests for identifying those at risk for this disease.

Endogenous sex steroids and bone mineral density in healthy Greek postmenopausal women

The aim of this study was to assess the association of endogenous sex steroids with bone mineral density (BMD) in healthy postmenopausal women not on hormone therapy. A total of 884 postmenopausal women aged 42-71 years were studied in a cross-sectional design. Parameters assessed were follicle-stimulating hormone, luteinizing hormone, estradiol, total testosterone, sex hormone-binding globulin, free estrogen index (FEI), free androgen index (FAI), Delta4-androstendione (Delta4A), dehydroepiandrosterone sulfate (DHEAS), bone alkaline posphatase, and bone mineral density at the lumbar spine (L-BMD) and femoral neck (N-BMD). Estradiol and FEI associated positively with both L-BMD and N-BMD (r = 0.21-0.47, P < 0.01). These associations remained significant after adjustment for age, years since menopause, and body mass index. FAI correlated positively with both L-BMD and N-BMD (r = 0.18 and 0.33, respectively; P < 0.01). At the multivariate analysis, however, FAI remained the significant determinant only for N-BMD. Delta4A associated positively with N-BMD (r = 0.27, P = 0.001), whereas DHEAS showed no association with BMD at either site. Thus, endogenous steroids are significant determinants of postmenopausal BMD. Endogenous estradiol may be more important for lumbar spine BMD, whereas endogenous androgens are associated mainly with femoral neck BMD.

Promotive effects of non-digestible disaccharides on rat mineral absorption depend on the type of saccharide

OBJECTIVE

We examined the effects of feeding non-digestible disaccharides, difructose anhydride III (DFAIII), maltitol, melibiose and, cellobiose, on calcium, magnesium, and iron absorption in comparison with fructo-oligosaccharide (FOS) in normal and ovariectomized rats.

METHODS

In experiment 1, six groups of male Sprague-Dawley rats were fed a control diet (100 g of cellulose/kg of diet), test diets containing 30 g of FOS, or the four non-digestible disaccharides in place of the cellulose in the control diet for 4 wk. In experiment 2, two groups of female Sprague-Dawley rats (sham or ovariectomized) were assigned to one of four subgroups and fed the control or test diet containing FOS, DFAIII, and melibiose for 5 wk. Feces and cecal contents were collected to evaluate mineral absorption and cecal fermentation.

RESULTS

In experiment 1, calcium absorption in all the disaccharides groups except the cellobiose group, magnesium absorption in all test diet groups, and iron absorption in the FOS, DFAIII, and melibiose groups were higher than those in the control group. In ovariectomized rats (experiment 2), calcium absorption in the DFAIII and melibiose groups, magnesium absorption in all test diet groups, and iron absorption in the DFAIII group alone were higher than those in the control group. Cecal organic acids were positively and pH was negatively correlated with the absorption of these minerals, although the effects varied.

CONCLUSION

Non-digestible disaccharides increase calcium, magnesium, and iron absorption in normal and ovariectomized rats; however, the effects depend on the disaccharide tested, a fact that may be partly associated with the cecal fermentation of these disaccharides.

Calcium Requirements for the Athlete

There is oftentimes a notion of "the more, the better" with regard to vitamin and mineral intake among individuals, and especially among athletes. Although adequate calcium intake is necessary to promote bone health and prevent osteoporosis, increased physical activity alone does not necessarily demand an increased intake of dietary calcium or other micronutrients. Athletes may lose calcium via sweat, in which case replenishment is advocated either via dietary intake of calcium-rich foods or a commercial calcium supplement. The important message to athletes is to consume a diet adequate in energy, protein, fat, vitamins, minerals, and fluids to support the physical demands and replenish the physiologic losses incurred with physical training.