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

Abstract

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, P = 0.03, and 11.0 ± 0.2 to 10.4 ± 0.2 m s, 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.

Effects of Montmorency tart cherry supplementation on cardio-metabolic markers in metabolic syndrome participants: A pilot study

“…In agreement with responses observed in MetS subjects during the present investigation, Johnson et al (2017) reported 12 weeks MTCJ consumption had no significant effect on lipids.…”

“…However, Johnson et al (2017) observed a trend for lower total cholesterol with MTCJ compared to PLA. This suggests lipids may be more sensitive to improvement at higher anthocyanin, secondary metabolite and phase II conjugate concentrations; through higher dosages and/or longer supplementation length.…”

“…Evidence exists that a higher consumption of anthocyanins is associated with reductions in aortic blood pressure and arterial stiffness (Jennings et al, 2012). Previous research pertaining to supplementation of MTCJ in healthy (Lynn et al, 2014), early-hypertensive (Keane et al, 2016b) and MetS (Johnson et al, 2017) participants had not demonstrated improvements in arterial stiffness. Individual responses and statistical analysis from the present study demonstrated an improvement in arterial stiffness (AIx) only at 2-hours post-bolus with MTCJ compared to PLA.…”

“…Hypertension and isolated systolic hypertension increases risk of CVD, the leading cause of morbidity and mortality worldwide (Feresin et al, 2017), however mean bSBP reductions of at least 5-6 mmHg over 5 years has been linked with a lower risk of coronary heart disease and stroke by 20-25% and 35-40%, respectively (Collins et al, 1990). Bundy et al (2017) reported that a reduction in bSBP of greater than 5 mmHg was clinically relevant and associated with lower CVD/mortality risk.…”

Effects of strawberry intervention on cardiovascular risk factors: a meta-analysis of randomised controlled trials

“…The biological and functional properties of strawberries have been studied in animal models (4) and extended to humans in a few epidemiological studies (7)(8)(9) . In the past decade, emerging interventional trials have been conducted to examine the health effects of strawberries in humans (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) . However, most of these trials had small sample sizes, which might have resulted in insufficient statistical power.…”