Laughter is the best medicine, or so the cliché goes. Actually, given the choice between laughter and, say, penicillin or chemotherapy, you’re probably better off choosing one of the latter. Still, a great deal of research shows that humor is extraordinarily therapeutic, mentally and physically.

Laughing in the face of tragedy seems to shield a person from its effects. A 2013 review of studies found that among elderly patients, laughter significantly alleviated the symptoms of depression [1]. Another study, published early this year, found that firefighters who used humor as a coping strategy were somewhat protected from PTSD [2]. Laughing also seems to ease more-quotidian anxieties. One group of researchers found that watching an episode of Friends (specifically, Season Five’s “The One Where Everybody Finds Out”) was as effective at improving a person’s mood as listening to music or exercising, and more effective than resting [3].

Laughter even seems to have a buffering effect against physical pain. A 2012 study found that subjects who were shown a funny video displayed higher pain thresholds than those who saw a serious documentary [4]. In another study, postsurgical patients requested less pain medication after watching a funny movie of their choosing [5].

Other literature identifies even more specific health benefits: laughing reduced arterial-wall stiffness (which is associated with cardiovascular disease) [6]. Women undergoing in vitro fertilization were 16 percent more likely to get pregnant when entertained by a clown dressed as a chef [7]. And a regular old clown improved lung function in patients with chronic obstructive pulmonary disease [8]. More generally, a mirthful life is likely to be a long one. A study of Norwegians found that having a sense of humor correlated with a high probability of surviving into retirement [9].

Unfortunately, there’s a not-so-funny footnote to all this: the people who are best at telling jokes tend to have more health problems than the people laughing at them. A study of Finnish police officers found that those who were seen as funniest smoked more, weighed more, and were at greater risk of cardiovascular disease than their peers [10]. Entertainers typically die earlier than other famous people [11], and comedians exhibit more “psychotic traits” than others [12]. So just as there’s research to back up the conventional wisdom on laughter’s curative powers, there also seems to be truth to the stereotype that funny people aren’t always having much fun. It might feel good to crack others up now and then, but apparently the audience gets the last laugh.

The Studies:

[1] Shaw, “Does Laughter Therapy Improve Symptoms of Depression Among the Elderly Population?” (PCOM Physician Assistant Studies dissertation, 2013)

[2] Sliter et al., “Is Humor the Best Medicine?” (Journal of Organizational Behavior, Feb. 2014)

[3] Szabo et al., “Experimental Comparison of the Psychological Benefits of Aerobic Exercise, Humor, and Music” (Humor, Sept. 2005)

[4] Dunbar et al., “Social Laughter Is Correlated With an Elevated Pain Threshold” (Proceedings of the Royal Society B, March 2012)

[5] Rotton and Shats, “Effects of State Humor, Expectancies, and Choice on Postsurgical Mood and Self-Medication” (Journal of Applied Social Psychology, Oct. 1996)

[6] Vlachopoulos et al., “Divergent Effects of Laughter and Mental Stress on Arterial Stiffness and Central Hemodynamics” (Psychosomatic Medicine, May 2009)

[7] Friedler et al., “The Effect of Medical Clowning on Pregnancy Rates After In Vitro Fertilization and Embryo Transfer” (Fertility and Sterility, May 2011)

[8] Brutsche et al., “Impact of Laughter on Air Trapping in Severe Chronic Obstructive Lung Disease” (International Journal of Chronic Obstructive Pulmonary Disease, March 2008)

[9] Svebak et al., “A 7-Year Prospective Study of Sense of Humor and Mortality in an Adult County Population” (The International Journal of Psychiatry in Medicine, June 2010)

[10] Kerkkänen et al., “Sense of Humor, Physical Health, and Well-Being at Work” (Humor, March 2004)

[11] Rotton, “Trait Humor and Longevity” (Health Psychology, July 1992)

[12] Ando et al., “Psychotic Traits in Comedians” (The British Journal of Psychiatry, May 2014)