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Surprising Side Effects of Marijuana After Age 40

Experts warn of five unexpected side effects of marijuana. 
FACT CHECKED BY Emilia Paluszek

While marijuana has typically been associated with teenage use, more older adults are smoking pot according to a study based on the National Survey of Drug Use and Health. Smoking weed has several benefits like reducing anxiety, inflammation and pain, helping with nausea from cancer treatments and more, but it can affect people differently in unexpected ways and cause surprising side effects you might not be aware of. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Increased Risk of Heart Disease

Young woman suffering from breathing problem near window indoors.

People who use marijuana regularly are at a greater risk for heart disease and heart attack, Stanford Medicine reports. According to a large study done by Stanford, "researchers analyzed the genetic and medical data of about 500,000 people ages 40-69. The data was from the UK Biobank. Nearly 35,000 participants reported smoking cannabis; of those, about 11,000 smoked more than once a month. The more-than-monthly smokers were significantly more likely than others in the study to have a heart attack after controlling for other factors including age, body mass index and sex. The researchers found that frequent marijuana smokers were also more likely than nonusers to have their first heart attack before the age of 50 — an unusual medical event called a premature heart attack that increases a person's lifelong risk of subsequent heart attack, heart failure and life-threatening arrhythmias that can cause sudden death."


The Effects May Not Kick in for Awhile

Female GP giving medical marijuana oil to patient.

Dr. Jacob Hascalovici MD, PhD as the Clearing Chief Medical Officer tells us, "Due to how some bodies process CBD, much of it may end up released at a slower rate than you're expecting, or it might even get stored in body fat. For my patients using CBD for pain relief, you may not notice symptom relief as rapidly or thoroughly as you might have been anticipating. It may help to take CBD with your meals instead of by itself."


CBD May Interact With Other Medications

Woman is holding a mobile phone and a bottle of pills

Dr. Hascalovici says, "Science is still learning more about how CBD may interact with other kinds of medications, but as far we know, it may not work "as usual" if you are also taking antifungals, anticonvulsants, blood thinners, St. John's Wort, and certain other medications and supplements. That's why it's important to make sure your doctor and pharmacist know what you're taking and that you ask about possible interactions."


Drowsiness and Dizziness Can Occur

Stressed unhappy woman touching forehead, suffering from strong headache or chronic migraine

"While this doesn't apply to everyone, drowsiness and dizziness can strike for some CBD users," says Dr. Hascalovici. "If you're already unsteady on your feet, you may want to be extra careful and make sure your living space is safety-proofed to guard against falls."


Your CBD or Medical Marijuana Products May Contain Unpleasant Surprises

man massaging nose bridge, taking glasses off, having blurry vision or dizziness

According to Dr. Hascalovici, "Since cannabis products and cannabis-derived products are not generally approved by the FDA for medical purposes, concerns could arise. Not only are these products not necessarily subject to adequate quality control when it comes to their CBD or THC content, they could also contain "inert" ingredients which wouldn't be considered active, but could still be concerning. Sesame seed oil and alcohol, to mention only two, could cause unwanted side effects."

Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. Heather currently freelances for several publications. Read more about Heather