Impact of Humor
While the research specifically looking at the impact of humor on heart health has only recently begun, what has been done is consistent with the findings discussed above for other sources of positive emotion (actually, one source - optimism) and suggests that humor can play an important role in promoting cardiac health in both healthy individuals and those who have already suffered a heart attack.
• Preventing Heart Disease. The first study to deal with this question was conducted in 2000 by Michael Miller, at the University of Maryland Medical School. Dr. Miller matched (by age) 150 people who had already had a heart attack or had undergone coronary artery bypass surgery with 150 individuals with no prior history of heart disease. The group which had had a heart attack was found (using a self-report questionnaire) to be 40% less likely than the heart-healthy individuals to laugh in a variety of different situations.117 An example of one of the situations is as follows: "If you were eating in a restaurant with some friends and the waiter accidentally spilled a drink on you, would you a) not find it particularly amusing, b) be amused but not show it outwardly, c) smile, d) laugh, or e) laugh heartily?"
|
The heart-attack group also reported feeling more anger and hostility. Their reduced laughter is not surprising in view of this second finding, since most people laugh less when they're angry. It is tempting to conclude that the group with no heart-disease suffered fewer heart attacks because they found more humor in life and laughed more. As with any correlational study, however, we can't really draw this conclusion. The study just establishes a significant association between laughter and heart attacks. It could also be that people were more angry and laughed less because they had had a heart attack in the past.
In addition to showing less laughter, individuals with CHD scored significantly lower on a measure of sense of humor. In fact, a weaker sense of humor predicted CHD even when the data were adjusted for other factors known to contribute to good/poor cardiac health, including hypertension, cholesterol level, cigarette smoking and family history of CHD.118 Also, as with the findings discussed above, individuals with a stronger sense of humor scored lower on a measure of anger/hostility. So this initial research certainly supports the idea that humor and laughter help sustain a healthy heart.
• Facilitating Recovery from Heart Disease. One exciting study has demonstrated the importance of keeping your sense of humor when you've already suffered a heart attack.119 This is a real challenge, since such life-threatening events generally rob people of their sense of humor and fun in life. People who had already suffered a myocardial infarction (heart attack) were randomly assigned to two groups before going through a standard cardiac rehab program for a period of a year. Some patients just went through the regular rehab program, going to the hospital three times a week. Others also watched a comedy video while they were there for their rehab procedure. Each patient got to choose the video watched, so they presumably selected one that was funny to them.
At the end of one year, the comedy-watching group had suffered significantly fewer additional heart attacks during the 12-month period, along with fewer episodes of cardiac arrhythmia. As noted earlier, the patients who watched comedy videos also had significantly lower blood pressure (there were no blood pressure differences between the groups at the beginning of the study). So humor plays an important role in promoting cardiac health even if you've already had a heart attack.
How Does Humor Promote Cardiac Health?
• By Reducing Stress-Linked Cardiovascular Reactivity. As noted above, we have known for years that the anger, tension and anxiety that generally go along with high stress have a negative impact on the heart, making a significant contribution to both CHD and hypertension.120 Barbara Fredrickson and her colleagues at the University of Michigan have done a series of studies suggesting that humor and other sources of positive emotion have the power to overcome this link. One of their studies, for example, showed that after negative emotion (and its accompanying increased cardiovascular reactivity) had been induced by watching a film, watching a subsequent humorous film produced a quicker recovery to the baseline of cardiovascular reactivity than did either a negative or neutral film.121 These researchers concluded that positive emotions (humor being only one path to positive emotion) appear to restore one to a state of physiological equilibrium following negative emotion or stress. This finding is of special importance, given the generally accepted view that chronic activation of the sympathetic nervous system (e.g., due to anger or feeling constantly "driven" to achieve, as discussed above in connection with the "Type A personality") may lead to cardiovascular disease.122
|
Fredrickson has argued, based on a series of studies along these lines, that humor - and positive emotion in general - undoes the lingering physiological reactivity that goes along with negative emotion. She has completed several experiments which support this view. In each case, a high-arousal negative emotion was first produced (activating the sympathetic nervous system). Subjects then watched a film that induced joy (high-activation positive emotion), contentment (low-activation positive emotion), neutrality, or sadness. In three different samples, subjects in both the high- and low-activation positive emotion conditions showed more rapid cardiovascular recovery from negative emotional arousal than subjects in the other two groups.123
In one of these studies, a humor video was used as the high-activation source of positive emotion. Subjects who watched the humor video showed significantly faster cardiovascular recovery than those who watched either a neutral or sadness-inducing video.124 So, as these researchers noted, the positive emotion associated with humor does have "the ability to regulate lingering negative emotional arousal."
• By Supporting a Healthy Inner Lining of Arteries. What else is there about humor and laughter that would reduce your risk of a heart attack? We saw in a previous section that stress and negative emotion cause a form of arterial dysfunction in which the endothelium of blood vessels shows reduced capacity to dilate/enlarge when called upon to do so. Dr. Michael Miller speculated at the time of his 2000 study that positive emotion might have just the opposite effect, increasing the ability of an artery to dilate when conditions call for it to do so. He noted in 2000 that "We don't yet know why laughing protects the heart, but we know that mental stress is associated with impairment of the endothelium, the protective barrier lining our blood vessels. This can cause a series of inflammatory reactions that lead to fat and cholesterol build-up in the coronary arteries and ultimately to a heart attack."125 Humor and laughter might somehow reverse these effects.
To check out this possibility, he completed a follow-up study in which he examined the effect of humor and laughter on the endothelium itself. He had subjects watch both a stress-inducing and funny video (with a two-day time lapse between videos). Some watched the former first, while others watched the latter first. He used the same blood pressure cuff procedure described above. That is, a standard arm blood pressure cuff was used to restrict blood flow for a period of time. When the cuff is removed, there is a sudden increase in blood flow in the brachial artery of the arm. Another device measured how well the artery responded (dilated) to accommodate the increased surge of blood. Watching a comedy movie segment led to a 22% increase (average across subjects) in blood flow in comparison to a pre-established baseline for each subject. This endothelium-relaxation effect occurred in 19 of the 20 participating subjects. Watching a stressful movie segment (the opening scene of Saving Private Ryan) had the opposite effect, leading to vasoconstriction and a 35% (average) decrease in blood flow.126 This amounts to a greater than 50% difference in the extent of artery dilation in response to the stressful and funny films. Dr. Miller noted that the magnitude of changes observed in the endothelium in response to humor is similar to those associated with aerobic exercise.
If this relaxation or dilation of blood vessels occurs in response to humor in a laboratory setting, it must also be occurring in everyday life among individuals with a good sense of humor - people who find more humor and laugh more at the office, with their family, etc. In both cases, the relaxation effect counters the ongoing artery constriction and associated elevation of blood pressure that accompanies stress.
|
Relaxation of the inner lining of arteries, then, (and the increased blood flow that results from this) may be the means by which humor and laughter help sustain a healthy heart. This is consistent with the finding that humor and laughter produce muscle relaxation, and the easing of psychological tension in the process. A direct result of this increased blood flow (associated with blood vessel dilation), of course, is lower blood pressure. The health risks associated with high blood pressure are well-established.
Nitric oxide (not nitrous oxide, or laughing gas) also appears to be produced when blood vessels expand. This reduces clotting and inflammation - a clear benefit in sustaining healthy arteries - while emotion-induced contraction of the endothelium is associated with increased cortisol, which may cause clotting.
An individual who has a better developed sense of humor, and is able to use humor to both minimize the level of stress experienced and more quickly reduce stress when it does occur, has blood vessels which go through fewer of the endless cycles of vasoconstriction and dilation which occur when we are frequently stressed through the day. Every rise in blood pressure puts extra stress on the inner walls of your arteries and may eventually lead to small tears in the walls. While your body does initiate a series of actions to repair the walls when such tears occur, there is every reason to think that in the long run this process leads to the eventual development of atherosclerotic plaque. If enough plaque builds up within coronary arteries, a heart attack may occur. Humor and laughter, then, can play a crucial role in slowing down this process.
• By Pulling You Out of a Negative Mood and Substituting a Positive Mood in its Place. Depression and emotional distress were shown earlier in this section to be significant predictors of mortality due to heart-related problems among both individuals in good and poor cardiac health. Humor's power to sustain a positive mood and substitute a positive for a negative mood if you're already angry, depressed, anxious or sad is discussed below. Given the ability of positive emotion to reduce cardiovascular reactivity, this mood-altering power of humor undoubtedly contributes to its ability to support a healthy heart.
