11 Scientific Benefits of Having a Laugh

iStock.com/Petar Chernaev
iStock.com/Petar Chernaev

They say that laughter is "the best medicine," and as it turns out, there is some scientific truth to this assertion. Humor-associated laughter has numerous health benefits, so here are 11 reasons you should laugh it up.

1. Laughter is a sign of good will toward others.

Group of friends laughing in a restaurant
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Laughter may be unique to humans. Why do we do it? According to a 2010 study in BMC Complementary and Alternative Medicine, laughter and smiling are generally intended as a message of good will. The authors extrapolate that there is a similar function in primates, who use facial expressions with bared teeth to suggest friendliness and sociability. They write, "Because some forms of smiling are voluntary and easily faked, laughter, which requires a more synergetic contraction of the wider musculature, is believed to have evolved in humans to express a secure, safe message to others."

2. Laughter may reduce your blood pressure.

Two girls laughing in a car
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High blood pressure (hypertension) is one of the most dangerous side effects of stress, as well as a huge risk factor for heart disease and stroke. However, it's hard to be stressed when you're laughing, so researchers have investigated whether laughter can bring blood pressure down. There are more than a few studies that show a reduction of blood pressure after laughter, such as a 2017 study in the Journal of Dental and Medical Research, where 40 patients undergoing hemodialysis listened to CDs of comic shows for 16 30-minute sessions over eight weeks, and saw a decrease in blood pressure.

In 2011 researchers presented results of a three-month-long study at the American Heart Association's Scientific Sessions. Researchers exposed 79 participants to either a music or laughter therapy. Laughter was stimulated through "playful eye contact" and breathing exercises. Immediately after sessions, the blood pressure readings from the laughers lowered by 7 mmHg—(millimeters of mercury, how the blood pressure readings on a sphygmomanometer are abbreviated). In comparison, music therapy only brought blood pressure down by 6 mmHg.

After three months, the blood pressure readings significantly decreased overall by 5 mmHg among the laughers. People in the comparison group showed no change in blood pressure readings.

3. This had led to a treatment known as laughter yoga.

group laughing in a workout class
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The success of laughter studies on blood pressure and other ills has led to a unique kind of treatment known as "laughter yoga."

Dr. Madan Kataria, founder of the Laughter Yoga School, told Medscape, "You don't need any jokes, any humor, or any comedy. You don't even need to be happy. What we do is laugh in a group and initiate laughter as a form of bodily exercise, but when we have eye contact with others, this laughter becomes real and contagious."

Kataria led a study of 200 male and female individuals who participated in laughter yoga sessions for 20 to 30 minutes. The researchers stimulated laughter in the participants for between 45 seconds and one minute, followed by deep breathing and stretching for the duration of the sessions.

Subjects who laughed saw a reduction in their systolic blood pressure of more than 6 mmHg, a significant change from baseline and also significant when compared with a non-laughing control group. Diastolic blood pressure was also significantly reduced. In addition, their levels of cortisol, a stress hormone, were also reduced.

As a result, laughter yoga has gone on to be used as an intervention for a variety of health issues, ranging from stress to dementia.

4. Laughter can reduce anxiety and other negative emotions.

Two guys laughing and shaking hands
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A 1990 study in Psychological Reports looked at the effects of humorous laughter on threat-induced anxiety. Researchers led 53 college students to believe (falsely) that they were going to receive an electric shock after a waiting period.

Subjects in the experiment group listened to a humorous tape while waiting for their shock. The placebo group listened to a non-humorous tape, and the control group did not listen to any tape. The humor group reported that their anxiety decreased during the anticipatory period, and those with the highest self-reported level of sense of humor had the lowest reported anxiety.

Laughter therapy has also been shown to improve anxiety in patients with Parkinson's disease [PDF], reduce anxiety and depression in nursing students, and improve optimism, self-esteem, and depression in menopausal women.

From a general psychological perspective, author Bernard Saper suggests in a paper for Psychiatric Quarterly that the ability to maintain a sense of humor and the ability to laugh can act as positive coping mechanisms to help a person get through difficult times.

5. Laughter is an immune booster.

Mom and boy laughing on couch
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At the beginning of cold and flu season, it may be a good idea to practice some laughter therapy, as several studies have shown the immune boosting power of a chuckle.

In one 2015 study on postpartum mothers in the Journal of Alternative and Complementary Medicine, researchers tested hand-expressed breast milk for immunoglobulin (IgA, antibodies that play an important role in immune function) before and after laughter therapy.

Twice a week, participants engaged in group "laughter dance routines" and some light breast massage while inducing laughter. Mothers who participated in the laughter therapy saw a small increase in their IgA. However, even a small amount was significant to the researchers, given that the postpartum period is when natural IgA in breast milk declines (it is at its highest level right after delivery, in the earliest, nutrient-dense breast milk known as colostrum).

Another study with college students found that watching funny movies increases salivary IgA (sIgA). Researchers have also found small examples of laughter's ability to increase the body's natural killer cells (NKs), a type of lymphocyte that is easy to test for in the blood. One study in the American Journal of Medical Science, albeit small—a cohort of only 10 male subjects—found significantly increased NK cell activity in the experimental group. Additional studies have shown increases in NK cell activity after laughter therapy or humorous videos, but most of these studies were done on male subjects.

6. Laughter may act as a natural anti-depressant.

woman laughing with dog
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While nobody would recommend laughter in lieu of other treatment for depression, it has shown promise at ameliorating depressed moods. Patients in long-term care facilities often suffer from depression and poor sleep, so a 2017 study in the Korean Journal of Adult Nursing [PDF] tested the effects of laughter therapy on 42 residents of two long-term care hospitals. The results were promising.

The laugher therapy, which the subjects undertook over eight sessions, for 40 minutes twice a week, included "singing funny songs, laughing for diversion, stretching, playing with hands and dance routines, laughing exercises, healthy clapping, and laughing aloud."

The results showed reduced depression and general mood improvement as well as improved sleep in the experiment group compared to the control group.

Another 2015 study in the Journal of Alternative and Complementary Medicine found that three 60-minute laughter therapy sessions improved the depression and negative mood states of cancer patients.

7. You breathe better after laughing.

grandfather and grandson laughing on ground
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It turns out that a good bout of deep belly laughter can lead to increased heart rate, respiratory rate, and oxygen consumption, which are similar to what happens during exercise. While a 2009 study in the International Journal of Humor Research found that these changes only last as long as the laughter itself, if you can laugh like that for 30 minutes to an hour, maybe you can skip the gym.

8. Laughter is good for your cardiovascular system.

women laughing at a movie
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Your lungs aren't the only organ that benefits from a great guffaw. A 2009 study in Medical Hypotheses found powerful benefits to the heart and cardiovascular system.

Study participants watched either a comedy like Saturday Night Live or the bleak opening sequence of Saving Private Ryan, which is known to increase mental stress. They used a technique called brachial artery reactivity testing (BART), a form of ultrasound that looks at the brachial artery. Participants who watched the stressful movie experienced a 35 percent reduction in flow-mediated vasodilation (FMD, or how blood vessels dilate and contract); sluggish FMD is a risk factor for atherosclerosis. Meanwhile, the group that watched the funny scene saw a 22 percent increase in FMD, comparable to exercise. In short, laughing helped their blood flow better.

The American Heart Association recommends laughter for a healthy heart, adding that research has shown laughter promotes reduced artery inflammation and increased production of HDL, or "good" cholesterol.

9. Laughter calms stress hormones.

man and woman laughing
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Humor, and by extension, laughter, stimulates multiple physiological systems that decrease levels of stress hormones, such as cortisol and epinephrine, and increase the activation of the dopamine-dispensing reward system of the brain, according to researchers of a 2017 study in Advances in Physiology Education. A 2003 study in Alternative Therapies in Health and Medicine found that viewing a funny film decreased a wide variety of stress hormones.

10. Social laughter can relieve pain.

Girl with broken arm laughing in doctor office
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Laughter might be as good as some analgesics for pain, something early physicians seemed to understand. In the 14th century, French surgeon Henri de Mondeville used humor to distract patients from the pain of surgery and to help them during recovery.

More modern research has found that participants who watched comedy videos needed less pain medication than those who watched control videos. In a 2011 study published in the Proceedings of the Royal Society, over the course of six experiments using extreme cold as a pain-tolerance measure, researchers found that social laughter—laughter done in groups in a social context—elevates pain thresholds. The authors suggest, "These results can best be explained by the action of endorphins released by laughter."

11. Laughing burns calories.

Woman laughing on a running trail.
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As if all of these benefits aren't a good enough reason to giggle every day, a 2014 study in the International Journal of Obesity found that laughter can burn calories. Researchers broke a group of 45 participants into two groups, half of whom watched film clips intended to evoke laughter for approximately 10 minutes, and half who watched film clips unlikely to stimulate laughter. Both groups were attached to a "calorimeter" that measured energy expenditure and heart rate. They determined that those who laughed during their viewing burned up to 10 calories in 10 minutes, as compared to those who did not laugh and did not burn any calories.

10 of the Most Popular Portable Bluetooth Speakers on Amazon

Altech/Bose/JBL/Amazon
Altech/Bose/JBL/Amazon

As convenient as smartphones and tablets are, they don’t necessarily offer the best sound quality. But a well-built portable speaker can fill that need. And whether you’re looking for a speaker to use in the shower or a device to take on a long camping trip, these bestselling models from Amazon have you covered.

1. OontZ Angle 3 Bluetooth Portable Speaker; $26-$30 (4.4 stars)

Oontz portable bluetooth speaker
Cambridge Soundworks/Amazon

Of the 57,000-plus reviews that users have left for this speaker on Amazon, 72 percent of them are five stars. So it should come as no surprise that this is currently the best-selling portable Bluetooth speaker on the site. It comes in eight different colors and can play for up to 14 hours straight after a full charge. Plus, it’s splash proof, making it a perfect speaker for the shower, beach, or pool.

Buy it: Amazon

2. JBL Charge 3 Waterproof Portable Bluetooth Speaker; $110 (4.6 stars)

JBL portable bluetooth speaker
JBL/Amazon

This nifty speaker can connect with up to three devices at one time, so you and your friends can take turns sharing your favorite music. Its built-in battery can play music for up to 20 hours, and it can even charge smartphones and tablets via USB.

Buy it: Amazon

3. Anker Soundcore Bluetooth Speaker; $25-$28 (4.6 stars)

Anker portable bluetooth speaker
Anker/Amazon

This speaker boasts 24-hour battery life and a strong Bluetooth connection within a 66-foot radius. It also comes with a built-in microphone so you can easily take calls over speakerphone.

Buy it: Amazon

4. Bose SoundLink Color Bluetooth Speaker; $129 (4.4 stars)

Bose portable bluetooth speaker
Bose/Amazon

Bose is well-known for building user-friendly products that offer excellent sound quality. This portable speaker lets you connect to the Bose app, which makes it easier to switch between devices and personalize your settings. It’s also water-resistant, making it durable enough to handle a day at the pool or beach.

Buy it: Amazon

5. DOSS Soundbox Touch Portable Wireless Bluetooth Speaker; $28-$33 (4.4 stars)

DOSS portable bluetooth speaker
DOSS/Amazon

This portable speaker features an elegant system of touch controls that lets you easily switch between three methods of playing audio—Bluetooth, Micro SD, or auxiliary input. It can play for up to 20 hours after a full charge.

Buy it: Amazon

6. Altec Lansing Mini Wireless Bluetooth Speaker; $15-$20 (4.3 stars)

Altec Lansing portable bluetooth speaker
Altec Lansing/Amazon

This lightweight speaker is built for the outdoors. With its certified IP67 rating—meaning that it’s fully waterproof, shockproof, and dust proof—it’s durable enough to withstand harsh environments. Plus, it comes with a carabiner that can attach to a backpack or belt loop.

Buy it: Amazon

7. Tribit XSound Go Bluetooth Speaker; $33-$38 (4.6 stars)

Tribit portable bluetooth speaker
Tribit/Amazon

Tribit’s portable Bluetooth speaker weighs less than a pound and is fully waterproof and resistant to scratches and drops. It also comes with a tear-resistant strap for easy transportation, and the rechargeable battery can handle up to 24 hours of continuous use after a full charge. In 2020, it was Wirecutter's pick as the best budget portable Bluetooth speaker on the market.

Buy it: Amazon

8. VicTsing SoundHot C6 Portable Bluetooth Speaker; $18 (4.3 stars)

VicTsing portable bluetooth speaker
VicTsing/Amazon

The SoundHot portable Bluetooth speaker is designed for convenience wherever you go. It comes with a detachable suction cup and a carabiner so you can keep it secure while you’re showering, kayaking, or hiking, to name just a few.

Buy it: Amazon

9. AOMAIS Sport II Portable Wireless Bluetooth Speaker; $30 (4.4 stars)

AOMAIS portable bluetooth speaker
AOMAIS/Amazon

This portable speaker is certified to handle deep waters and harsh weather, making it perfect for your next big adventure. It can play for up to 15 hours on a full charge and offers a stable Bluetooth connection within a 100-foot radius.

Buy it: Amazon

10. XLEADER SoundAngel Touch Bluetooth Speaker; $19-$23 (4.4 stars)

XLeader portable bluetooth speaker
XLEADER/Amazon

This stylish device is available in black, silver, gold, and rose gold. Plus, it’s equipped with Bluetooth 5.0, a more powerful technology that can pair with devices up to 800 feet away. The SoundAngel speaker itself isn’t water-resistant, but it comes with a waterproof case for protection in less-than-ideal conditions.

Buy it: Amazon

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

The Meteoric Rise—and Tragic Fall—of NASA's Skylab

NASA // Public Domain
NASA // Public Domain

On May 14, 1973, NASA launched Skylab, the first American space station. It fell to earth six years later, burning up in the atmosphere on July 11, 1979.

Skylab itself was a heavily modified third stage of a Saturn V rocket—the same system we used to send Apollo missions to the moon. The station was huge, measuring more than 80 feet in length, with a 21-foot diameter. During launch, Skylab 1 suffered major damage to its solar array, which delayed the launch of the Skylab 2 crew (originally intended to launch the day after Skylab itself reached orbit). The Skylab 2 mission was modified to include repair work to the solar power system and installation of a solar heat shield, as the original one was lost during launch. The Skylab 2 crew launched on May 25, 1973.

The Skylab missions resulted in new information about long-term space habitation (including an awesome space shower). The first crew spent 28 days in space; the second crew more than doubled that at 59 days; and the final crew (Skylab 4) spent 84 days up there. That last record was not broken by an American for two decades. Skylab also focused on solar science, Earth science, and microgravity experiments.

Skylab was something of a bridge between the Apollo and Space Shuttle programs. Indeed, Skylab was supposed to be serviced (and its orbit boosted) by the first Shuttle, but it wasn't ready in time. Skylab's orbit decayed, eventually causing it to disintegrate and fall to Earth over the Indian Ocean on July 11, 1979. Chunks of the station made a bit of a fireworks display streaking through the atmosphere, and ultimately littered a swath of Australia. No injuries were reported from the falling debris, though media coverage of the reentry was intense.

Here's a short NASA documentary on Skylab, explaining the story of the station. Have a look:

If you'd like to relive the launch, here's live TV coverage from that day:

And if you'd like to learn more about its crash, and what it taught NASA moving forward, watch this:

This story has been updated for 2020.