Professor Sumnall argues that while it could be effective for some people, in some of these cases the results could be caused by the placebo effect (where the patient’s belief in a treatment makes them feel better). The placebo effect can be powerful, but Professor Sumnall warns that if people try CBD oil instead of speaking to their doctor, it could cause a problem.
CBD, or cannabidiol, is a chemical that’s extracted from the leaves and flowers of the cannabis plant. Cannabis itself is an illegal class B drug, as is the compound THC (tetrahydrocannabinol) which it contains. But pure CBD isn’t illegal, as it doesn’t cause the intoxicating effects of cannabis.
Prices can be high: a 500mg bottle of CBD oil oral drops could set you back as much as £45. Not that this has put people off: over the past two years, sales of CBD have almost doubled in the UK, putting regular users at an estimated quarter of a million.
What is CBD used for?
Many of these can be easily picked up from reputable high street stores, such as Holland & Barrett or Boots.
The choice of CBD products has exploded recently: you can buy oils, capsules, muscle gels, sprays and oral drops, as well as beer, tea, sweets, hummus and even CBD-infused clothing.
Harry Sumnall, Professor in Substance Use at Liverpool John Moores University, says: “In terms of the products found in shops, there’s virtually no evidence to support the claims made for a lot of them. There’s a lot of marketing that says CBD is a ‘miracle of the modern age’; however, the marketing has actually overtaken the evidence of what it’s effective for.”
But so far, Professor Sumnall points out, CBD products in shops are marketed as food supplements, not medicines, so none of them have gone through this process.
Some research suggests that CBD oil may improve some heart-related symptoms:
“CBD oil may not have the same properties, and it can actually cause gastrointestinal distress like diarrhea or cause decreased appetite. CBD products can include unknown ingredients and may not be accurately labeled,” he says.
What We Know About CBD
Larry Allen, MD, MHS, University of Colorado Anschutz Medical Campus.
“Does it stimulate your appetite? Yes. Do people gain weight if they take it? Possibly true. Patients with severe heart failure do have cachexia,” or severe weight loss and muscle wasting, he says. “One could argue that people with nausea, lack of appetite, or who are losing weight could think CBD would help them. People with heart failure have a fair amount of discomfort, including edema [swelling] and somatic or pain-related issues, so you could think CBD has a role.”
Oxidative Medicine and Cellular Longevity: “Therapeutic Applications of Cannabinoids in Cardiomyopathy and Heart Failure.”
Since cannabinoids also mop up free radicals — and improve the effects of other antioxidants in the body — CBD may also protect against heart disease by reducing the cellular damage that happens when we’re exposed to free-radical producers like processed foods and environmental pollution.
Research shows that CBD can help maintain healthy cardiovascular function and prevent heart disease on a number of fronts, including protecting against hardening of the arteries, lowering blood pressure, and reducing the incidence of potentially dangerous arrhythmias.
If you’re already taking medications for blood pressure, cholesterol, or other heart conditions, it’s important to consult with your doctor before you start taking CBD . High doses of CBD may interfere with the metabolism of some of these drugs, which could have problematic consequences.
Inside Your Arteries
Research shows that CBD also can suppress irregular heartbeat caused by stroke-induced ischemia (inadequate blood supply to the heart) and can minimize tissue damage caused by the lack of oxygen. A study published in the British Journal of Pharmacology found that when rats were given CBD 10 minutes before a 30-minute coronary artery occlusion (partial or complete obstruction of blood flow in the coronary artery, which may cause chest pain, heart attack, and tissue damage) or 10 minutes before blood flow was restored, they experienced fewer arrhythmias and less tissue damage than rats not given CBD . Research in this area is still in the early stage, but it already shows great potential.
Heart disease is a catchall phrase for the disease that develops when the arteries of the heart cannot deliver enough oxygen-rich blood to the heart, leading to events like heart attack. It’s the leading cause of death in the United States, killing about 655,000 Americans each year, which is about one in every four deaths. Key risk factors for heart disease include unhealthy diet, physical inactivity, diabetes, overweight and obesity, and excessive alcohol use.
In a follow-up study, where the researchers gave 26 men 600 mg of CBD or a placebo for seven days, the results were mixed. Measurements of resting blood pressure revealed that the participants had developed a tolerance to the CBD over time, but CBD ’s ability to lower blood pressure during stress persisted. (Of course, if you are already dealing with low blood pressure, the blood pressure–reducing effects of CBD are something to be aware of, and you may need to avoid high doses.)
CBD may also protect against cardiac arrhythmias, or irregular heartbeats, where the heart beats too fast, too slowly, or with an irregular pattern. Arrhythmias can be brought on by long-term stress, as high cortisol levels can raise blood pressure, blood cholesterol, blood sugar, triglycerides, and other risk factors for heart disease in general. CBD ’s anti-anxiety properties can help combat stress, lower cortisol, and protect against arrhythmias related to those causes.