Citrus flavanones boost endothelial function and heart health
It is known that a moderate to high fat meal exerts a temporary impairment on the function of blood vessels, and this could ultimately affect endothelial dysfunction and the risk of developing cardiovascular disease during one’s lifetime.
New data published in the British Journal of Nutrition indicates that co-consumption of flavanone-rich orange juice with a meal may counteract these detrimental transient effects, and support heart health in healthy middle-aged men.
“[O]ur results suggest that acute intake of a beverage containing at least 128 mg of flavanones can be an effective dietary strategy to blunt the acute transient impairment in endothelial function induced by a sequential double meal that reflects a typical intake in the population,” wrote the authors, led by Dr Catarina Rendeiro.
“Although we cannot draw firm conclusions regarding the mechanisms by which flavanones elicit vascular responses, our results suggest that these might be linked to an ability of flavanone metabolites to sustain basal circulating NO levels.
“Collectively, these observations have important implications, considering that most individuals spend the majority of the day in the postprandial state, and such temporary vascular changes repeated on a daily basis can critically impact on long-term vascular health and overall chronic disease risk.”
Study details
Dr Rendeiro and her co-workers recruited 59 healthy men aged between 30 and 65 to participate in their study. The men visited the lab on four separate occasions and each time given a high fat breakfast and a moderate-fat lunch 5.5. hours later along with one of four different interventions: A control drink; orange juice; flavanone-rich orange juice; or a whole orange beverage.
Results showed that endothelial function, as measured by flow-mediated dilatation (FMD) of the brachial artery, was impaired by the double meal and the control drink. However, all of the orange interventions blunted this impairment.
The researchers noted that the effects on FMD coincided with the highest levels of specific flavanone metabolites in the blood of the male participants, specifically metabolites of naringenin and hesperetin.
Dr Rendeiro and her co-workers also reported that, while nitrate levels decreased significantly in all of the groups, the flavanone drinks were associated with constant levels of nitrite, while these levels declined in the control group.
“Nitrite plasma levels are known to reflect more accurately endogenous NO production in humans (estimate of 70–80 % of plasma nitrite deriving from eNOS activity), whereas the other major source is diet-derived nitrate (by reduction to nitrite),” they explained. Nitric oxide – NO – is a potent vasodilator, or blood vessel relaxant.
The researchers said that their findings are consistent with data from other randomized controlled trials using cocoa flavanol interventions. “To our knowledge, this is the first set of data indicating that citrus flavanones are also capable of attenuating postprandial impairments in endothelial function following a sequential high–medium-fat double meal in individuals displaying mild cardiometabolic risk factors,” they wrote.
Source: British Journal of Nutrition
Published online ahead of print, doi: 10.1017/S0007114516004219
“Flavanone-rich citrus beverages counteract the transient decline in postprandial endothelial function in humans: a randomised, controlled, double-masked, cross-over intervention study”
Authors: C. Rendeiro et al.
