Research dating back to the 1970s has found that cannabis reduces blood pressure. Now, a study published in the Journal of Clinical Investigation has discovered that you don’t need the psychoactive stuff to benefit from the herb’s relaxant effects. Cannabidiol (CBD), a cannabis compound that does not cause a psychotropic “high”, can reduce blood pressure after a single dose.
The small study, which tested nine adult male volunteers, was first published in June of 2017. The research was conducted by scientists at England’s University of Nottingham. A research team compared the effects of CBD versus a placebo control on a variety of different cardiovascular functions. A high dose of CBD was used – 600 milligrams, to be exact.
The CBD was administered in just one single dose.
The team looked at CBD’s effect on blood pressure, heart rate, forearm skin blood flow, and stroke volume. Stroke volume is a measurement of blood pumped from the left ventricle of the heart. The left ventricle is the portion of the heart responsible for getting oxygen-rich blood out of the heart and into other organs.
Participants underwent different stress tests and researchers measured their cardiac responses. One stress test was an exercise test and another was a test using cold temperatures.
As a positive, CBD successfully reduced systolic blood pressure while both resting and under stress. This confirmed what the scientists had expected – CBD blunted the cardiac responses to stress.
Blood pressure typically increases in stressful situations. This puts you at greater risk for a heart attack and can have negative effects on heart health over time. The finding that CBD can reduce blood pressure after a single dose is exciting, but not surprising.
The compound, along with other cannabis components, are vasodilators. That means that they can release tension in the arteries and allow more blood to flow into organs. In theory, this could allow more oxygen to flow into tissues and possibly help those with conditions like hypertension.
However, the researchers did come across some results that warrant further research. While the molecule did lower blood pressure, it also caused an increase in heart rate. This was coupled with a decreased stroke volume. A decreased stroke means that the heart has to pump faster to put out oxygen-rich blood.
With exercise, the researchers found that CBD increased heart rate by 10 beats per minute. Yet, the team found no difference between the total output of nutritious blood in CBD consumers or those given the placebo. The authors write,
We have shown for the first time that to our knowledge that, in humans, acute administration of CBD reduces resting blood pressure, with a lower stroke volume and a higher heart rate.
According to the study authors, earlier studies have used the same dosage of CBD and the compound did not increase heart rate. In this study, men who had never tried cannabis were given a very high dose of CBD for the first time. In earlier studies, consumers given high-dose CBD were familiar with cannabis and its effects.
The researchers suggest that consumers may become tolerant to the effects of CBD on heart rate over time. Still, this research confirms that the compound successfully reduces blood pressure and holds potential as a future heart medicine. CBD’s effects on heart rate and what that ultimately means for consumers will need to be investigated.