Cocoa packs powerful blood pressure-lowering properties — and your gut is one reason why

Studies continue to show that cocoa flavanols can lower blood pressure and arterial stiffness just like the best blood pressure medications. However, scientists have had some concern that consuming cocoa when your blood pressure is normal or low could lower it even further. Now, a new study finds there’s nothing to worry about! Researchers in Australia say cocoa only lowers blood pressure when it’s abnormally high, with the gut playing a key role in the process.

The new study notes that previous experiments have only looked at cocoa’s beneficial impact on the heart under tightly controlled conditions. This has made it unclear as to whether cocoa also lowers blood pressure in already healthy people.

A team from the University of Surrey says their study is one of the first to look at cocoa consumption and its impact on the heart in a real-world scenario.

“High blood pressure and arterial stiffness increases a person’s risk of heart disease and strokes, so it is crucial that we investigate innovative ways to treat such conditions,” says Christian Heiss, a professor of cardiovascular medicine, in a university release.

“Before we even consider introducing cocoa into clinical practices, we need to test if the results previously reported in laboratory settings safely translate into real-world settings, with people going about their everyday lives.”

Your gut loves metabolizing chocolate

In their study, 11 healthy people consumed six cocoa flavanol capsules or six placebo capsules on alternate days for a week. Each participant received an upper arm blood pressure monitor and a finger clip measuring pulse wave velocity (PWV) — which gauges a patient’s arterial stiffness.

The group took these readings every 30 minutes after consuming cocoa or the brown sugar placebos for three hours. They continued to monitor their blood pressure and pulse wave velocity hourly for another nine hours after that.

Results show that consuming cocoa only led to lower blood pressure and arterial stiffness in participants where those readings were already high. There was no effect when blood pressure was low in the morning.

Moreover, the study was also the first to find an additional peak in cocoa’s beneficial effect eight hours after consumption. The team believes this second peak in the readings likely has a connection to how bacteria in the gut metabolizes cocoa flavanols.

“The positive impact cocoa flavanols have on our cardiovascular system, in particular, blood vessel function and blood pressure, is undeniable. Doctors often fear that some blood pressure tablets can decrease the blood pressure too much on some days,” Prof. Heiss concludes.

“What we have found indicates that cocoa flavanols only decrease blood pressure if it is elevated. Working with participants’ personal health technologies showed us how variable blood pressure and arterial stiffness can be from day to day and shows the role of personal health monitors in developing and implementing effective personalized care.”

The study is published in the journal Frontiers in Nutrition.