Effects of strawberries on bone biomarkers in pre- and stage 1-hypertensive postmenopausal women: a secondary analysis

Postmenopausal women experience an increase in bone remodeling with the rate of bone resorption superseding the rate of bone formation. This results in a net bone loss with a subsequent increased risk for osteoporosis and fractures. High blood pressure (BP) has been associated with loss of bone mineral density and increased propensity to fractures. Strawberries are rich in polyphenols, which have been shown to have anti-hypertensive and bone-protective properties. Thus, we examined whether daily intake of strawberries would positively affect biomarkers of bone metabolism in postmenopausal women with pre- and stage 1-hypertension. Participants (age: 59 ± 6 years; body mass index: 31.5 ± 4.1 kg m^-2; systolic BP: 140 ± 13 mmHg) were randomly assigned to consume (1) 50 g of freeze-dried strawberry powder (FDSP), (2) 25 g FDSP + 25 g of placebo powder, or (3) 50 g placebo powder for eight weeks. Results indicate a significant time-by-treatment interaction (P = 0.04) for serum insulin-like growth factor (IGF)-1, a hormone that plays a major role in bone formation. Serum concentrations of bone-specific alkaline phosphatase, a marker of bone formation, and tartrate-resistant acid phosphatase-5b, a specific marker of bone resorption, were not affected by FDSP compared to placebo. Although not statistically significant, after eight weeks, osteocalcin increased in the 50 g FDSP group with a large effect size (d = 0.6) when compared to the placebo-control group. Adiponectin increased by 5% and 6% in the 25 g and 50 g FDSP groups, respectively, while it declined in the placebo-control group by 25% (P = 0.03 for time-by-treatment interaction). Our findings suggest that consumption of 25 g FDSP increases IGF-1 in postmenopausal women with pre- and stage 1-hypertension. However, further studies are needed to assert the effectiveness of a strawberry intervention for bone health.

Effects of Montmorency Tart Cherry Juice Consumption on Cardiometabolic Biomarkers in Adults with Metabolic Syndrome: A Randomized Controlled Pilot Trial

Greater than one-third of adults in the United States have metabolic syndrome (MetS), a cluster of risk factors highly associated with the development of cardiovascular diseases. Premature vascular dysfunction in MetS may lead to accelerated age-related atherogenesis and arterial stiffening, thereby increasing cardiovascular risk. Montmorency tart cherries (Prunus cerasus L.) are rich in bioactive compounds, such as anthocyanins, known to exert cardiovascular protective effects. Previous research suggests that tart cherry juice consumption may improve cardiovascular health. The objective of this study was to evaluate the effects of daily consumption of tart cherry juice on hemodynamics, arterial stiffness, and blood biomarkers of cardiovascular and metabolic health in men and women with MetS. In a randomized, single-blind, placebo-controlled, parallel-arm pilot clinical trial, 19 men and women 20 to 60 years of age with MetS consumed 240 mL of tart cherry juice (Tart Cherry; n = 5 males, 4 females) or an isocaloric placebo-control drink (Control; n = 5 males, 5 females) twice daily for 12 weeks. Arterial stiffness (pulse wave velocity), brachial and aortic blood pressures, wave reflection (augmentation index), and blood biomarkers of cardiovascular and metabolic health were assessed at baseline and 6 and 12 weeks. Oxidized low-density lipoprotein and soluble vascular cell adhesion molecule-1 were significantly lower (P = .047 and P = .036, respectively) in Tart Cherry than Control at 12 weeks, but were not significantly lower than baseline values. There was a trend for total cholesterol to be lower (P = .08) in Tart Cherry than Control at 12 weeks. No significant changes were observed in hemodynamics, arterial stiffness, or other blood biomarkers assessed. These results suggest that daily tart cherry consumption may attenuate processes involved in accelerated atherogenesis without affecting hemodynamics or arterial stiffness parameters in this population. The pilot nature of this study warrants interpreting these findings with caution, and future clinical trials with a larger sample size are needed to confirm these findings.

The Relationship between Protein Intake and Source on Factors Associated with Glycemic Control in Individuals with Prediabetes and Type 2 Diabetes

Type 2 diabetes (T2D) is a major contributor to morbidity and mortality largely due to increased cardiovascular disease risk. This study examined the relationships among protein consumption and sources on glycemic control and cardiovascular health in individuals with prediabetes and T2D. Sixty-two overweight or obese participants with prediabetes or T2D, aged 45–75 years were stratified into the following three groups based on protein intake: <0.8 g (gram)/kg (kilogram) body weight (bw), ≥0.8 but <1.0 g/kg bw, and ≥1.0 g/kg bw as below, meeting, and above the recommended levels of protein intake, respectively. Body mass, body mass index (BMI), hip circumference (HC), waist circumference (WC), lean mass, and fat mass (FM) were significantly higher in participants who consumed below the recommended level of protein intake as compared with other groups. Higher animal protein intake was associated with greater insulin secretion and lower triglycerides (TG). Total, low-density, and high-density cholesterol were significantly higher in participants who met the recommended protein intake as compared with the other groups. These data suggest that high protein consumption is associated with lower BMI, HC, WC, and FM, and can improve insulin resistance without affecting lipid profiles in this population. Furthermore, higher intake of animal protein can improve β-cell function and lower plasma TG.

Influence of daily fresh pear consumption on biomarkers of cardiometabolic health in middle-aged/older adults with metabolic syndrome: a randomized controlled trial

Previous research suggests potential for fresh pears as a functional food for promoting cardiometabolic health. The purpose of this randomized, open-label, placebo-controlled, crossover clinical trial was to evaluate the influence of daily fresh pear consumption on blood pressure (primary outcome) and other biomarkers of cardiometabolic health in middle-aged/older adults with metabolic syndrome (MetS). Forty men and women aged 45-65 years with MetS were included and randomly assigned to receive either two medium-sized fresh pears (Pear) or a calorie-matched control drink (Control) per day for each 12-week treatment period, each separated by a 4-week washout period. After 12 weeks of daily fresh pear consumption, systolic blood pressure tended to be reduced (130 ± 2 mmHg vs. 134 ± 2 mmHg at baseline, P = 0.07) and pulse pressure was significantly reduced (51 ± 1 vs. 54 ± 1 at baseline, P < 0.05). At 12 weeks, leptin concentrations were lower in the Pear group than Control (52.5 [7.6, 120.5] ng dL-1vs. 53.4 [5.0, 120.5] ng dL-1, respectively, P < 0.05), and there was a significant group by time interaction (P < 0.05). Leptin concentrations were significantly reduced at 12 weeks compared to baseline in the Pear group (52.5 [7.6, 120.5] ng dL-1vs. 54.8 [6.4, 120.5] ng dL-1 at baseline, P < 0.05) but not in the Control group. Waist circumference was significantly reduced at 12 weeks in the Pear group (107.7 ± 2.0 cm vs. 108.4 ± 2 cm at baseline, P < 0.05) with a trend for a group by time interaction (P < 0.1), and significantly lower in the Pear group than Control (108.1 ± 2.0 cm vs. 108.8 ± 2 cm, P < 0.05) at 6 weeks with a significant group by time interaction (P < 0.05). Conversely, values were significantly increased at 6 weeks (108.8 ± 2 cm vs. 108.3 ± 2.0 cm at baseline, P < 0.05) in the Control group and sustained at 12 weeks. Waist-to-hip ratio was significantly reduced (0.92 ± 0.01 vs. 0.93 ± 0.01 at baseline, P < 0.05) at 12 weeks in the Pear group, and significantly lower than Control at 6 weeks (0.93 ± 0.01 vs. 0.93 ± 0.01, respectively, P < 0.05) and 12 weeks (0.92 ± 0.01 vs. 0.93 ± 0.01, P < 0.05). These findings suggest that daily fresh pear consumption may promote modest improvements in cardiometabolic health in middle-aged/older adults with MetS. This trial was registered at clinicaltrials.gov as NCT02228837.

Dietary Protein Intake Associations with Insulin Resistance, BMI, Body Composition and Other Metabolic Markers in Subjects with Prediabetes and Type 2 Diabetes Mellitus (P08-020-19)

Objectives

The incidence of prediabetes and type 2 diabetes mellitus (T2DM) continues to increase and many individuals are not aware of having early stages of the disease until symptoms develop. Much focus has been on carbohydrate consumption for this population, with no established recommendations for protein intake and source. Therefore, the objective of this study was to examine the relationship between protein intake (amount and source) on glycemic control, and indices of cardiovascular health in individuals with prediabetes and T2DM.

Methods

Sixty-two overweight and obese men and women with prediabetes or T2DM, between the ages of 45–75 years participated in this study. Participants were stratified based on their protein intake: below (<0.8 g/kg body weight (bw); n = 17), meeting (0.8–1.0 g/kg bw; n = 22), and above (≥1.0 g/kg bw; n = 23) recommended levels. Measurements included blood biomarkers (lipid panel and glycemic control), anthropometric parameters, food records, and body composition, which were assessed for each group using one-way ANOVA and Pearson correlation coefficient for overall associations. Significance was accepted at (P ≤ 0.05).

Results

Body mass index (BMI), hip circumference (HC) and waist circumference (WC) were significantly higher in participants who consumed below recommended levels compared to above (35.1 ± 1.3 vs. 28.3 ± 0.9 kg/m2; 118.7 ± 3.2 vs. 105.2 ± 1.8 cm; 109.1 ± 2. vs. 96.8 ± 2.5 cm, respectively). Fat-to-lean mass (FM/LM) ratio was significantly lower in participants who consumed above recommended when compared to below and recommended levels (0.63 ± 0.03; 0.81 ± 0.04; 0.78 ± 0.07). Insulin resistance tended to be lower (3.53 ± 0.55 vs 5.19 ± 0.94; P = 0.09) in the above recommended group compared to below. Higher animal-to-plant protein ratios were significantly associated with higher insulin secretion (r = 0.259). Higher animal protein was associated with significantly lower triglyceride concentrations (r = 0.263).

Conclusions

These findings suggest that consumption of ≥1.0 g/kg bw protein was associated with lowered insulin resistance, in addition to lower BMI, HC, WC, and FM, without adverse effects on lipid profiles in this population. Additionally, increased animal protein may be associated with better outcomes for this population.

Funding Sources

There are no funding sources to disclose for this study.

Impact of daily strawberry consumption on blood pressure and arterial stiffness in pre- and stage 1-hypertensive postmenopausal women: a randomized controlled trial

Growing evidence indicates that strawberries are cardioprotective. We conducted an eight-week randomized, double-blind, placebo-controlled, parallel arm clinical trial to investigate the effects of daily consumption of freeze-dried strawberry powder (FDSP) on blood pressure (BP) and arterial stiffness in pre- and stage 1-hypertensive postmenopausal women. Sixty postmenopausal women were randomly assigned to one of three groups: (1) control, (2) 25 g FDSP and (3) 50 g FDSP (n = 20 per group). Assessments of body weight, BP, arterial stiffness as measured by pulse wave velocity (PWV), and collection of blood samples for analyses of vasoactive and antioxidant molecules were performed at baseline, four and eight weeks. After eight weeks, systolic BP, as well as brachial- and femoral-ankle PWV were lower than baseline in the 25 g FDSP group (141 ± 3 to 135 ± 3 mmHg, P = 0.02; 15.5 ± 0.5 to 14.8 ± 0.4 m s^-1, P = 0.03, and 11.0 ± 0.2 to 10.4 ± 0.2 m s^-1, P = 0.02, respectively), whereas no statistically significant changes were observed in the control or 50 g FDSP groups. Plasma nitric oxide metabolite levels increased at four and eight weeks in the 50 g FDSP group compared to baseline (8.5 ± 1.2 to 13.6 ± 1.3 and 13.3 ± 1.5, respectively, P = 0.01), whereas no significant changes were observed in the control or 25 g FDSP groups. Serum levels of superoxide dismutase increased at four weeks returning to baseline levels at eight weeks in all three groups. Significant differences among groups were not detected for any of the parameters. Although BP and arterial stiffness improved in the 25 g FDSP group over time, a treatment effect was not observed. Thus, it would be premature to affirm that daily consumption of FDSP improves BP or vascular function in pre- and stage 1-hypertensive postmenopausal women. This trial was registered at as NCT02099578.

Egg consumption may improve factors associated with glycemic control and insulin sensitivity in adults with pre- and type II diabetes

Daily consumption of one large egg for 12 weeks improves fasting blood glucose, ATP-binding cassette protein family A1, and apolipoprotein A1 in overweight or obese individuals with pre- and type II diabetes.

Effects of daily blueberry consumption on circulating biomarkers of oxidative stress, inflammation, and antioxidant defense in postmenopausal women with pre- and stage 1-hypertension: a randomized controlled trial

Blueberries may attenuate accelerated age-related chronic disease development in postmenopausal women.

Daily blueberry consumption improves blood pressure and arterial stiffness in postmenopausal women with pre- and stage 1-hypertension: a randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

Postmenopausal women have a high prevalence of hypertension and often develop arterial stiffness thereby increasing cardiovascular disease risk. Although antihypertensive drug therapies exist, increasing numbers of people prefer natural therapies. In vivo studies and a limited number of clinical studies have demonstrated the antihypertensive and vascular-protective effects of blueberries.

OBJECTIVE

To examine the effects of daily blueberry consumption for 8 weeks on blood pressure and arterial stiffness in postmenopausal women with pre- and stage 1-hypertension.

DESIGN

This was an 8-week, randomized, double-blind, placebo-controlled clinical trial.

PARTICIPANTS/SETTING

Forty-eight postmenopausal women with pre- and stage 1-hypertension recruited from the greater Tallahassee, FL, area participated.

INTERVENTION

Participants were randomly assigned to receive either 22 g freeze-dried blueberry powder or 22 g control powder.

MAIN OUTCOME MEASURES

Resting brachial systolic and diastolic blood pressures were evaluated and arterial stiffness was assessed using carotid-femoral pulse wave velocity and brachial-ankle pulse wave velocity. C-reactive protein, nitric oxide, and superoxide dismutase were measured at baseline, 4 weeks, and 8 weeks.

STATISTICAL ANALYSES PERFORMED

Statistical analysis was performed using a split plot model of repeated measures analysis of variance.

RESULTS

After 8 weeks, systolic blood pressure and diastolic blood pressure (131±17 mm Hg [P<0.05] and 75±9 mm Hg [P<0.01], respectively) and brachial-ankle pulse wave velocity (1,401±122 cm/second; P<0.01) were significantly lower than baseline levels (138±14 mm Hg, 80±7 mm Hg, and 1,498±179 cm/second, respectively), with significant (P<0.05) group×time interactions in the blueberry powder group, whereas there were no changes in the group receiving the control powder. Nitric oxide levels were greater (15.35±11.16 μmol/L; P<0.01) in the blueberry powder group at 8 weeks compared with baseline values (9.11±7.95 μmol/L), whereas there were no changes in the control group.

CONCLUSIONS

Daily blueberry consumption may reduce blood pressure and arterial stiffness, which may be due, in part, to increased nitric oxide production.