Data from a double-blind, randomized, controlled, crossover trial with 48 healthy postmenopausal women indicated that grapefruit juice consumption was associated with significant reductions in carotid-femoral pulse wave velocity, which is a measure of aortic stiffness.
“Our results support that some bioactive compounds abundant in grapefruit, particularly flavanones, may prevent arterial stiffening,” wrote the researchers in the American Journal of Clinical Nutrition. “These results have potential implications for public health, but dietary recommendations regarding the intake of grapefruit products for the whole population cannot yet be provided. Indeed, grapefruits also contain furanocoumarins, which can interact with the metabolism of a variety of drugs.
“To overcome this difficulty, the citrus industry is making great efforts to evolve toward grapefruit products low in these phytochemicals by altering grapefruit varieties, agronomic practices, postharvest treatments, processing, and storage.”
The study was funded by the Florida Department of Citrus.
Scientists from the French National Institute for Agricultural Research (INRA), and the French National Institute for Health and Medical Research (INSERM) recruited healthy women who were three to 10 years post-menopause, and randomly assigned them to consume grapefruit juice (340 ml per day) or a control drink for six months. The grapefruit juice contained 210 mg naringenin glycosides. A two month ‘washout’ period followed the intervention, and the participants were then crossed over to the other group.
The results showed that mean carotid-femoral pulse wave velocity (PWV) was 7.36 m/s in the grapefruit juice group, compared to 7.70 m/s in the control group. The reduction was statistically significant.
On the other hand, no changes were observed for other measures of cardiovascular health, including endothelial function, blood pressure, or markers of inflammation and oxidative stress.
“The PWV measured between the carotid and femoral arteries is considered the gold-standard measurement of central arterial stiffness and strongly correlates with cardiovascular events and all-cause mortality,” wrote the researchers. “The magnitude of the difference in PWV values between GFJ and CD (-0.524 m/s) after the 6-month consumption period could correspond to an absolute approximate 5% reduction in the global CVD risk.
“The present RCT provides the first clinical evidence of the vasculoprotective property of flavanones in subjects who regularly consume grapefruit juice. It should be noted that this effect was observed for an intake of flavanones equivalent to about 40% of the estimated daily intake of flavonoids. This finding is consistent with recent epidemiologic studies reporting an inverse association between citrus flavanone intake and the risk of CVDs.”
Source: American Journal of Clinical Nutrition
Published online ahead of print, doi: 10.3945/ajcn.114.104646
“Flavanones protect from arterial stiffness in postmenopausal women consuming grapefruit juice for 6 mo: a randomized, controlled, crossover trial”
Authors: V. Habauzit, M-A. Verny, D. Milenkovic, et al.