Low Energy Availability with and without a High-Protein Diet Suppresses Bone Formation and Increases Bone Resorption in Men: A Randomized Controlled Pilot Study

Suppression of insulin-like growth factor 1 (IGF-1) and leptin secondary to low energy availability (LEA) may contribute to adverse effects on bone health. Whether a high-protein diet attenuates these effects has not been tested. Seven men completed three five-day conditions operationally defined as LEA (15 kcal kg fat-free mass (FFM)-1 day-1) with low protein (LEA-LP; 0.8 g protein·kg body weight (BW)-1), LEA with high protein (LEA-HP; 1.7 g protein·kg BW-1) and control (CON; 40 kcal·kg FFM-1·day-1, 1.7 g protein·kg BW-1). In all conditions, participants expended 15 kcal·kg FFM-1·day-1 during supervised cycling sessions. Serum samples were analyzed for markers of bone turnover, IGF-1 and leptin. The decrease in leptin during LEA-LP (-65.6 ± 4.3%) and LEA-HP (-54.3 ± 16.7%) was greater than during CON (-25.4 ± 11.4%; p = 0.02). Decreases in P1NP (p = 0.04) and increases in CTX-I (p = 0.04) were greater in LEA than in CON, suggesting that LEA shifted bone turnover in favour of bone resorption. No differences were found between LEA-LP and LEA-HP. Thus, five days of LEA disrupted bone turnover, but these changes were not attenuated by a high-protein diet

Low Energy Availability with and without a High-Protein Diet Suppresses Bone Formation and Increases Bone Resorption in Men: A Randomized Controlled Pilot Study

Suppression of insulin-like growth factor 1 (IGF-1) and leptin secondary to low energy availability (LEA) may contribute to adverse effects on bone health. Whether a high-protein diet attenuates these effects has not been tested. Seven men completed three five-day conditions operationally defined as LEA (15 kcal kg fat-free mass (FFM)−1·day−1) with low protein (LEA-LP; 0.8 g protein·kg body weight (BW)−1), LEA with high protein (LEA-HP; 1.7 g protein·kg BW−1) and control (CON; 40 kcal·kg FFM−1·day−1, 1.7 g protein·kg BW−1). In all conditions, participants expended 15 kcal·kg FFM−1·day−1 during supervised cycling sessions. Serum samples were analyzed for markers of bone turnover, IGF-1 and leptin. The decrease in leptin during LEA-LP (−65.6 ± 4.3%) and LEA-HP (−54.3 ± 16.7%) was greater than during CON (−25.4 ± 11.4%; p = 0.02). Decreases in P1NP (p = 0.04) and increases in CTX-I (p = 0.04) were greater in LEA than in CON, suggesting that LEA shifted bone turnover in favour of bone resorption. No differences were found between LEA-LP and LEA-HP. Thus, five days of LEA disrupted bone turnover, but these changes were not attenuated by a high-protein diet

Risedronate or exercise for lean mass preservation during menopause: secondary analysis of a randomized controlled trial

Abstract Background The menopause transition is marked by hormonal shifts leading to body composition changes, such as fat mass gain and lean mass loss. Weight‐bearing and resistance exercise can help maintain lean mass during the menopause transition; however, uptake is low. Preclinical research points to bisphosphonates as also being effective in preventing loss of lean mass. Thus, we sought to investigate whether bisphosphonate therapy can mitigate loss of lean mass and outperform weight‐bearing exercise in the years immediately following menopause. Methods Data come from the Heartland Osteoporosis Prevention Study (NCT02186600), where osteopenic, postmenopausal women were randomized to bisphosphonate (n = 91), weight‐bearing/resistance exercise (n = 92), or control (n = 93) conditions over a 1 year period. Dual‐energy X‐ray absorptiometry‐derived body composition measures (including total lean mass, total fat mass, lean mass index, and lean‐to‐fat mass ratio) were ascertained at baseline, 6 months, and 12 months. Adherence to risedronate and weight‐bearing exercise was defined as the percentage of dosages taken and exercise sessions attended. Intent‐to‐treat analysis using linear modelling was used to generate treatment effects on body composition. Secondary analysis utilized per‐protocol analysis and included adjustment for weight change. Results A total of 276 women (age: 54.5 years; 83.3% Caucasian; body mass index: 25.7 kg/m2) were included in the analyses; 12 month adherence to the risedronate and exercise interventions was 89% and 64%, respectively. Group‐by‐time interactions were observed for lean mass, revealing that exercise (0.43 ± 1.49 kg) and risedronate groups (0.31 ± 1.68 kg) gained significantly more lean mass than control group (−0.15 ± 1.27 kg) over 12 months. However, after controlling for weight change in secondary analysis, the difference in lean mass change between control and risedronate became non‐significant (P = 0.059). Conclusions Results suggest that both 12 months of oral risedronate and 12 months of weight‐bearing exercise may diminish lean mass loss experienced during the menopause transition as compared with control. The lean mass‐sparing effect for risedronate may be driven by overall weight change

Moderate Exercise of 120 Minutes per Week Improves Aerobic Fitness and Waist Circumference but Not Insulin Sensitivity in Persons with Elevated Fasting Glucose

Aim. As the vast majority of those at risk for type 2 diabetes mellitus (T2DM) fail to meet the recommended 150 minutes of moderate physical activity per week, the primary purpose of this study was to determine whether an exercise program consisting of a total of 120 min of moderate-intensity exercise/week would improve insulin sensitivity in persons with impaired glucose tolerance. Methods. The effect of an 8-wk program of treadmill walking (4 sessions per week of 30 min duration at 40-60% of heart rate reserve) on insulin resistance was determined in a sample of sedentary adults (N.=29, 43.6 ± 11.15 yr) with a fasting glucose between 95 - 125 mg/dL (102.2 ± 10.91 mg /dL). Fasting insulin and glucose and fasting indices of insulin sensitivity were determined. Oral glucose tolerance tests data were used in several quantitative insulin sensitivity models. Blood lipids, blood pressure, aerobic capacity and anthropometric data were also collected before and after the exercise intervention. Results. Training resulted in a reduction in waist circumference and an increase in estimated aerobic capacity but no change in any measures of insulin sensitivity. Conclusion. Several published studies in normoglycemic subjects have reported significant improvements in markers of insulin sensitivity with exercise of similar volume and intensity to that of the current investigation. The results of this study suggest that the threshold dose and/or the intensity of exercise necessary to improve clinical markers of insulin sensitivity in those with impaired glucose tolerance may be higher than that required for normoglycemic subjects

The Impact of a Virtual Educational Cooking Class on the Inflammatory Potential of Diet in Cancer Survivors

(1) Background. Cognitive dysfunction is prevalent among cancer survivors. Inflammation may contribute to impaired cognition, and diet represents a novel strategy to mitigate cognitive decline. The purpose was to (1) assess the impact of an educational cooking class on cancer survivor eating habits and their inflammatory potential and (2) determine the relationship between diet and cognitive function. (2) Methods. This was a non-randomized interventional study of a virtual educational cooking class in post-treatment, adult cancer survivors. Energy-adjusted Dietary Inflammatory Index (E-DII™) scores and subjective cognitive function were assessed at baseline and 1 month post-intervention. (3) Results. Of 22 subjects, all were female, White, and primarily had breast cancer (64%). There was a significant decrease in E-DII scores, which became more anti-inflammatory, one month after intervention (−2.3 vs. −2.7, p = 0.005). There were significant increases in cognition, including perceived cognitive impairment (COG-PCI, p p p p = 0.04; 95% CI (0.000, 0.014)). (4) Conclusions. Educational cooking classes may be an effective way to impact diet-derived inflammation; additional research is needed to assess the long-term effects of dietary changes on cognition

Smallpox Vaccination of Laboratory Workers at US Variola Testing Sites

To evaluate the need to revaccinate laboratory workers against smallpox, we assessed regular revaccination at the US Laboratory Response Network’s variola testing sites by examining barriers to revaccination and the potential for persistence of immunity. Our data do not provide evidence to suggest prolonging the recommended interval for revaccination