The daily consumption of the equivalent of 336 grams of chokeberries was associated with decreases in daytime blood pressure (BP) and low-grade inflammation, according to findings published in Nutrition Research.
“[O]ur study showed that consumption of chokeberry juice and powder for 8 weeks had minor but favorable effects on CVD risk factors in metabolically healthy individuals with mildly elevated BP,” wrote researchers from the Finnish National Institute for Health and Welfare, Turku University, the University of Helsinki, and Natural Resources Institute Finland.
“The favorable effect seen on blood pressure was small and short lived suggesting that the use of chokeberries as blood pressure lowering treatment is limited. Although effects of this magnitude are not pharmacologically relevant, they are likely to become meaningful if these types of products are consumed in combination with other healthy foods and are incorporated into a generally healthy diet,” they added.
The study adds to the ever growing body of evidence supporting the potential health benefits of chokeberry, which was once used for enhancing the diets of Russian astronauts.
The majority of the science supporting the potential health benefits of chokeberry relate to heart health (enhancing blood flow, normalizing blood clots, benefiting blood pressure), but other reported benefits include anti-inflammatory effects, antioxidant activity, and immunomodulatory effects. A study from the International Journal of Sport Nutrition and Exercise Metabolism also indicated potential for sports nutrition (2005, Vol. 15, pp. 48-58).
The Finnish researchers recruited 38 people to participate in their single blind crossover trial. Participants were randomly assigned to receive 300 ml per day of cold-pressed 100% chokeberry juice, three grams per day of an oven-dried chokeberry powder, or placebo for 8 weeks each with no washout period.
Results showed that chokeberry consumption was associated with decreases in daytime blood pressure (daytime ambulatory diastolic blood pressure decreased by an average of 1.64 mmHg), as well as markers of inflammation, such as interleukin (IL) 10 and tumor necrosis factor alpha (TNF-alpha) decreased.
On the other hand, no effects were observed for lipids, lipoproteins, glucose and platelet aggregation were recorded by the researchers
Commenting on the potential mechanism of action, the researchers noted that compounds from chokeberry may weakly inhibit the angiotensin converting enzyme (ACE), while data from other studies suggests blood pressure may be reduced via nitric oxide (NO) related mechanisms,
“An NO-mediated vasodilatation and BP reduction induced by polyphenols may be short-lived and explain why ambulatory BP in our study tended to decrease only during the daytime,” they wrote. “In our study, chokeberries decreased daytime ambulatory DBP but only tended to decrease daytime SBP. This finding may be only a result of chance.
“On the other hand, NO-mediated vasodilatation takes place in smaller resistance arteries rather than in larger conduit arteries. Increased diastolic blood pressure reflects increased peripheral resistance and increased systolic blood pressure also increased stiffness of the large arteries. Accordingly, one might expect that the BP-lowering effects of chokeberries would be seen predominantly for diastolic BP.”
Source: Nutrition Research
Published online ahead of print, doi: 10.1016/j.nutres.2016.09.005
“Consumption of chokeberry (Aronia mitschurinii) products modestly lowered blood pressure and reduced low-grade inflammation in subjects with mildly elevated blood pressure”
Authors: B-M. Loo et al.