Eating a cup of blueberries every day may help your blood pressure, suggests a new study. The results, published online Feb. 16, 2019, by The Journals of Gerontology, Series A: Biological Sciences and Medical Sciences, found that consuming 200 grams of blueberries (about one cup) daily can improve blood vessel function and decrease systolic blood pressure (the top number in a blood pressure reading).
Researchers recruited 40 healthy men and randomly gave them either a drink containing 200 grams of whole wild blueberries or a control drink (which looked and tasted much the same) every day for a month. The team also monitored the men’s blood pressure as well as the flow-mediated dilation of the brachial artery in their upper arms. This measures how the artery widens when blood flow increases and is a marker of reduced cardiovascular disease risk.
Afterward, the researchers found that flow-mediated dilation improved by about 2% within two hours of consuming the blueberry drink and the effect was sustained after one month of daily consumption. Also, systolic blood pressure fell by an average of 5 millimeters of mercury. The effect was similar to that from common blood pressure drugs over the same period.
The experts pointed to the blueberries’ high levels of anthocyanins as the possible reason. Anthocyanins are the phytochemicals that give blueberries their dark color. (While all berries contain anthocyanins, blueberries have one of the highest levels.)
The research also showed that anthocyanins improve the function of endothelial cells in the body. These cells line the inner surface of blood vessels and help with blood flow and blood pressure regulation. The researchers added that blueberries may not only help control high blood pressure, but also may prevent people from developing hypertension.