Calcium supplementation, particularly with vitamin D, has been an approved public health intervention to reduce fracture risk. Enthusiasm for this intervention has been mitigated by meta-analyses suggesting that calcium supplementation with or without vitamin D increases myocardial infarction (MI) risk; however, concern has been raised over the design of these meta-analyses. We, therefore, undertook a meta-analysis of randomized controlled trials with placebo or no-treatment control groups to determine if these supplements increase all-cause mortality and coronary heart disease (CHD) risk including MI, angina pectoris and acute coronary syndrome, and chronic CHD verified by clinical review, hospital record, or death certificate in elderly women. The Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE databases were searched from January 1, 1966, to May 24, 2013, for potentially eligible studies, reference lists were checked, and trial investigators were contacted where additional unpublished data were required. The search yielded 661 potentially eligible reports of which 18 met the inclusion criteria and contributed information on 63,563 participants with 3390 CHD events and 4157 deaths. Two authors extracted the data independently with trial data combined using random-effects meta-analysis to calculate the relative risk (RR). Five trials contributed CHD events with pooled relative RR of 1.02 (95% confidence interval [CI], 0.96-1.09; p ¼ 0.51). Seventeen trials contributed all-cause mortality data with pooled RR of 0.96 (95% CI, 0.91-1.02; p ¼ 0.18). Heterogeneity among the trials was low for both primary outcomes (I 2 ¼ 0%). For secondary outcomes, the RR for MI was 1.08 (95% CI, 0.92-1.26; p ¼ 0.32), angina pectoris and acute coronary syndrome 1.09 (95% CI, 0.95-1.24; p ¼ 0.22) and chronic CHD 0.92 (95% CI, 0.73-1.15; p ¼ 0.46). In conclusion, current evidence does not support the hypothesis that calcium supplementation with or without vitamin D increases coronary heart disease or all-cause mortality risk in elderly women.
Obesity has reached epidemic proportions worldwide. The health consequences of obesity are more dangerous when associated with the metabolic syndrome and its components. Studies show that whey protein and its bioactive components can promote greater benefits compared to other protein sources such as egg and casein. The aim of this paper is to review the effects of whey protein on cardiometabolic risk factors. Using PubMed as the database, a review was conducted to identify current scientific literature on whey protein and the components of the metabolic syndrome published between 1970 and 2012. Consumption of whey protein seems to play an anti-obesity and muscle-protective role during dieting by increasing thermogenesis and maintaining lean mass. In addition, whey protein has been shown to improve glucose levels and insulin response, promote a reduction in blood pressure and arterial stiffness, and improve lipid profile. The collective view of current scientific literature indicates that the consumption of whey protein may have beneficial effects on some symptoms of the metabolic syndrome as well as a reduction in cardiovascular risk factors.
J Clin Hypertens (Greenwich). 2012; 14:848–854. ©2012 Wiley Periodicals, Inc. The authors investigated the effects of moderate‐intensity resistance, aerobic, or combined exercise on blood pressure and arterial stiffness in overweight and obese individuals compared with no exercise. Participants were randomized to 4 groups: control, aerobic, resistance, and combination. Assessments were made at baseline, week 8, and week 12. In participant‐designated responders, those in the intervention groups who had improved levels of systolic blood pressure (SBP) or augmentation index (AI), we observed a significant decrease of SBP in aerobic (−4%, P=.027), resistance (−5.1%, P=.04), and combination groups (−6.3%, P=.000) at week 8 and in the combination group (−6.3%, P=.005) at week 12, compared with baseline. AI was significantly lower at week 12 in the aerobic (−12%, P=.047), resistance (−9.5%, P=.036), and combination (−12.7%, P=.003) groups compared with baseline, as well as in the combination group (−10.7%, P=.047) compared with the control group. We did not observe significant changes in SBP, DBP, or AI between the interventions when assessing the entire cohort, although there were significant improvements in a subgroup of responders. Thus, some but not all overweight and obese individuals can improve blood pressure and arterial stiffness by participating in regular combination exercise, decreasing the risk of developing cardiovascular disease.
Physical activity seems to enhance cardiovascular fitness during the course of the lifecycle, improve blood pressure, and is associated with decreased prevalence of hypertension and coronary heart disease. It may also delay or prevent age-related increases in arterial stiffness. It is unclear if specific exercise types (aerobic, resistance, or combination) have a better effect on blood pressure and vascular function. This review was written based on previous original articles, systematic reviews, and meta-analyses indexed on PubMed from years 1975 to 2012 to identify studies on different types of exercise and the associations or effects on blood pressure and vascular function. In summary, aerobic exercise (30 to 40 minutes of training at 60% to 85% of predicted maximal heart rate, most days of the week) appears to significantly improve blood pressure and reduce augmentation index. Resistance training (three to four sets of eight to 12 repetitions at 10 repetition maximum, 3 days a week) appears to significantly improve blood pressure, whereas combination exercise training (15 minutes of aerobic and 15 minutes of resistance, 5 days a week) is beneficial to vascular function, but at a lower scale. Aerobic exercise seems to better benefit blood pressure and vascular function.
The aim of the present study was to assess the effects of a high protein (HP) and a normal protein (NP) diet on patients with polycystic ovary syndrome (PCOS) and body mass index-matched controls in a sample of southern Brazilian women. This 8-week randomized trial was carried out at a university gynecological endocrinology clinic and included 18 patients with PCOS and 22 controls. Changes in weight, body composition, hormone, and metabolic profile were analyzed in women randomized to receive HP (30% protein, 40% carbohydrate, and 30% lipid) or NP (15% protein, 55% carbohydrate, and 30% lipid). The energy content was estimated for each participant at 20-25 kcal/kg current weight/day. Physical activity, blood pressure, homeostasis model assessment (HOMA) index, and fasting and 2-h glucose and insulin remained stable during the intervention in PCOS and controls, even in the presence of weight loss. There were no changes in lipid profile in either group. In contrast, body weight, body mass index (BMI), waist circumference, percent of body fat, and sum of trunk skinfolds decreased significantly after both diets in both groups. Total testosterone also decreased in PCOS and controls regardless of diet. In conclusion, calorie reduction, rather than protein content, seemed to affect body composition and hormonal profile in this short-term study. These findings emphasize the role of non-pharmacological interventions to reduce weight and ameliorate the anthropometric and clinical phenotype in PCOS.
Previous studies suggest that dairy intake may be associated with reduced bone and muscle loss with aging, but there are limited data in the very old. We evaluated the association between intake of dairy foods and peripheral bone structure and muscle mass in 564 elderly women aged 80 to 92 (mean 84.7) years, who were participants of the Calcium Intake Fracture Outcome Study/CAIFOS Aged Extension Study (CAIFOS/CARES) cohort and attended the 10-year follow-up. Assessments included dairy consumption (milk, yogurt, and cheese) by a validated food frequency questionnaire, 15% tibia bone mass, area and volumetric bone mineral density (vBMD) by peripheral quantitative computed tomography (pQCT), and appendicular bone and skeletal muscle mass by dual-energy X-ray absorptiometry (DXA). Women were categorized according to tertiles of dairy intake: first tertile ( 1.5 servings/d), second tertile (1.5 to 2.2 servings/d) and third tertile (!2.2 servings/d). Controlling for confounding factors, pQCT assessment at the 15% tibia showed that compared with those in the first tertile of dairy intake, women in the third tertile had 5.7% greater total bone mass (p ¼ 0.005), principally because of an increase in cortical and subcortical bone mass (5.9%, p ¼ 0.050), resulting in a 6.2% increase in total vBMD (p ¼ 0.013). Trabecular but not cortical and subcortical vBMD was also higher (7.8%, p ¼ 0.044). DXA assessment showed that women in the third tertile of dairy intake had greater appendicular bone mass (7.1%, p ¼ 0.007) and skeletal muscle mass (3.3%, p ¼ 0.014) compared with tertile 1. The associations with bone measures were dependent on dairy protein and calcium intakes, whereas the association with appendicular muscle mass was not totally dependent on dairy protein intake. Our results suggest a positive association of dairy intake with appendicular bone mineralization and muscle mass in elderly women. Because many fractures in this age group are of the appendicular skeleton often associated with falls, dairy intake may be a modifiable lifestyle factor contributing to healthy aging.
Infertility, associated with oligo/anovulation, increased ovarian volume, numerous follicular cysts, and metabolic disturbances such as obesity and insulin resistance (IR) are characteristics common to polycystic ovary syndrome (PCOS), the most common endocrine disorder in women of reproductive age. Here, we show that New Zealand obese (NZO) mice display similar metabolic characteristics such as obesity, leptin insensitivity, glucose intolerance, and IR. Importantly, NZO mice are poor breeders; however, the mechanism for this has not been investigated. The aim of this study was to assess the ovarian structure/morphology and sex hormone levels in female NZO and lean C57BL/6J control mice. Twenty-five NZO and twenty female control mice were studied at three different ages (young, adult, and aged). The animals were weighed, an insulin tolerance test was carried out, and blood was collected for measurement of hormone levels. The ovaries were removed for histological analysis. As expected, NZO mice presented higher body weights (PZ0 . 001), increased basal plasma glucose (PZ0 . 007), and insulin levels (PZ0 . 001) as well as IR, compared with control mice. NZO mice showed an increased ovarian volume, reduced numbers of corpora lutea, and higher total follicle numbers (PZ0 . 0001). The number of primordial follicles increased (PZ0 . 02) at the young stage, as well as the amount of atretic follicles (PZ0 . 03), in NZO compared with control mice. NZO mice also displayed reduced plasma LH and increased estradiol levels. In conclusion, NZO mice show a poor breeding performance due to decreased ovulation, increased number of primordial and atretic follicles, and ovarian size. Given that NZO mice are obese, hyperinsulinemic and insulin resistant, they are suitable for investigating pathophysiological mechanisms linking metabolic alterations with reproductive defects.
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