Cocoa Lowers Blood Pressure

For people with existing hypertension, containing cocoa flavonoids helped reduce blood pressure and arterial stiffness, according to a small study in Frontiers in Nutrition.

Is cacoa the same as cacao?

The cacao bean is the source of both cacao and cocoa powders. Cacao beans are found inside the fruit of the Theobroma cacao tree in fleshy, oval-shaped pods. When you see cacao nibs, powdered cacao (or cacao powder) in the Grocery stores, the bean is in its raw state uncooked, additive free, and unprocessed. When cacao beans are roasted and processed they are called “cocoa”. Most cocoa powders have additives like sweeteners or cocoa butter. Once roasted and processed (turning cacao to cocoa), the beans lose much of their nutritional benefits. Natural unsweetened cocoa powder is very similar to raw cacao powder except for experiencing higher temperatures during production, which decreases antioxidant activity. Chocolate is made using varying degrees of either cacao or cocoa depending on the manufacturer’s choice

Study Details

Previous trials back up these findings — in fact, some research suggests that cocoa flavonoids lower blood pressure and arterial stiffness as much as certain blood pressure medications. However, the effectiveness of flavonoids in everyday settings was unknown, as previous studies were performed in tightly controlled experimental settings.

The current research, performed at the University of Surrey in England, also helps alleviate concerns that cocoa flavonoids pose health risks for those with normal or low blood pressure — it does not decrease blood pressure in those with normal or low levels.

This is the first real-world study on cocoa flavonoids and blood pressure. “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,” says Christian Heiss, Professor of Cardiovascular Medicine at the University of Surrey.

For several days, 11 healthy participants consumed, on alternating days, either six cocoa flavonoid capsules  or six placebo capsules containing brown sugar.

Participants were given an upper arm blood pressure monitor and a finger clip measuring pulse wave velocity (PWV) that gauges levels of arterial stiffness.

Measurements of blood pressure and PWV were taken prior to consumption of the capsules and every 30 minutes after ingestion for the first three hours, and then hourly for the remaining nine hours. Researchers found that blood pressure and arterial stiffness were only lowered in participants if their readings were high — and there was no effect when blood pressure readings were low in the morning.

Benefits were also reported eight hours after ingestion of the cocoa capsules. Researchers believe that this second peak may be due to how bacteria in the gut metabolise cocoa flavonoids.

“What we have found indicates that cocoa flavonoids 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 personalised care,” says professor Heiss.

Conclusion of the study
In conclusion, the study confirms that cocoa can improve vascular function and decrease blood pressure and arterial stiffness not only within the first 3 h after ingestion but also later at 8 h in healthy  people. The study uncovers considerable intra- and inter-individual variation in responses using an innovative n-of-1 study design with personal devices. With this approach, the researchers uncovered baseline blood pressure as a major determinant of response in healthy young people. The data highlight the need for personal health monitors to develop and implement effective personalised
care.

Reference

Bapir, M., Campagnolo, P., Rodriguez-Mateos, A., Skene, S. S., & Heiss, C. (2022). Assessing Variability in Vascular Response to Cocoa With Personal Devices: A Series of Double-Blind Randomized Crossover n-of-1 Trials. Frontiers in nutrition, 9, 886597. https://doi.org/10.3389/fnut.2022.886597