Laughter has been called "the best medicine" for many decades — and now there’s scientific proof.
A study from the Hospital de Clínicas de Porto Alegre in Brazil has shown that regular chuckling expands heart tissue and promotes the flow of oxygen in the body, thus reducing the risk of cardiac disease.
"Laughter therapy" was also shown to improve the health of those who already had heart disease.
"Our study found that laughter therapy increased the functional capacity of the cardiovascular system," said the lead author, Professor Marco Saffi, when presenting the study’s findings at the annual meeting of the European Society of Cardiology in Amsterdam this week.
The randomized study, which was published in ESC 365, included a total of 26 patients averaging 63 years of age, 69% of whom were male.
All of them were previously diagnosed with coronary artery disease, which occurs when plaque builds up in the arteries and can restrict the flow of blood to the heart.
Half of the patients watched two hour-long comedy shows on TV each week for a three-month period, and the other half watched two "neutral documentaries."
At the end of the study period, the group that watched the comedy programs showed a 10% greater flow of oxygen compared to the other group, indicating a stronger and healthier heart.
The comedy watchers also demonstrated improved expansion of the arteries and reduced inflammation of the heart.
"When patients with coronary artery disease arrive at the hospital, they have a lot of inflammatory biomarkers," said Saffi in the presentation.
"Inflammation is a huge part of the process of atherosclerosis, when plaque builds up in the arteries … This study found that laughter therapy is a good intervention that could help reduce inflammation and decrease the risk of heart attack and stroke."
Regular chuckles have also been shown to release endorphins and lower stress levels, which could also benefit heart health, he noted.
The researcher suggested that various types of laughter therapy could be used in hospitals and treatment plans to help reduce patients’ risk of cardiac events and perhaps lessen the reliance on medication.
"People should try to do things that make them laugh at least twice a week," he said.
This was the first randomized controlled trial to measure the impact of laughter therapy cardiac rehabilitation on patients with coronary artery disease, the study authors noted.
Alexandra L. Kharazi, M.D., a cardiothoracic surgeon with CVTS Medical Group in San Diego, California, was not involved in the research but noted that the results are encouraging, even though the study is small.
"However, it shouldn’t deflect from the fact that the best therapy for heart disease is lifestyle modification and risk factor modification," she told Fox News Digital.
"In other words, it’s great to make sure your day is filled with laughter, but you still need to take your blood pressure and cholesterol medication if you have coronary artery disease," she went on.
No amount of laughter therapy will reverse severe coronary blockages, as these often require stents or open-heart surgery, Kharazi noted.
The core benefit she recognizes in this research is laughter’s potential role in recovery after heart procedures.
"From personal experience, people who have a positive attitude post-operatively tend to have more energy to participate in activities, including physical therapy, which helps speed up recovery after open-heart surgery," the doctor said.
Dr. Heather Sandison, a renowned expert in Alzheimer's disease and related dementia care, also reviewed the study’s findings and found the results "exciting."
"Although this study was small, it is consistent with other research we have seen showing that laughter improves levels of stress hormones and immune function," she told Fox News Digital.
"It is exciting to see research on non-pharmaceutical interventions that are essentially risk- and cost-free and can reduce significant health concerns like cardiovascular disease," she went on.
"This gives patients a fun therapy to consider trying at home in addition to the typical medications and interventions they get from their doctor."