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Lots of people eat too much, smoke cigarettes, don't exercise, are depressed, have diabetes, and have cholesterol plaques in their hardening arteries—while others of the same age are thriving.
But this grouping of factors relevant to heart disease is a very misleading mish-mash. Health professionals and laypeople alike commonly make a serious error that leads to less than optimal treatment and interventions.
Smoking, over-eating, and physical inactivity are risk factors for disease, including heart disease. If you’re a regular smoker and you spend your days lounging around stuffing your face with cookies, your risk of disease goes up—way up. Still, there are many obese, sedentary smokers who stay healthy for many years. Risk factors increase your risk but are not perfect predictors. Most people with lung cancer are smokers—but most smokers do not get lung cancer.
But smoking, over-eating, and physical inactivity are also more than risk factors; they are causes of disease. The relevant scientific studies are difficult to do, and the causal inferences are complicated to make, but there is convincing evidence that if we intervene to create a population of non-smoking, active, fit individuals, we will have a much healthier population—healthier meaning less disease like diabetes and atherosclerosis and less premature mortality. People will thrive and live longer.
Recently, a number of experts have cited depression as a risk factor for heart disease. You may have seen the headlines in the news. The claim emerges because depression is reliably correlated with heart disease. If you are clinically depressed, you are more likely to have heart disease and have worse outcomes. It is also well established that if you are happy and have a high sense of subjective well-being, you are less likely to have heart disease.
The problem? There is little reason to think that depression is a significant cause of heart disease.
This means that many strategies for treating depression will not reduce risk of heart disease. In fact, there are many excellent studies showing that treating depression can make you feel better and function better, but not do anything for your heart.
Many people believe that happiness leads to health, and that depression leads to disease because, observably, the two often appear hand-in-hand. This does not mean that happiness is a direct cause of good health, or that depression is a direct cause of disease.
In much research by ourselves and others, and reported in part in our book on The Longevity Project, Dr. Leslie Martin and I have found that in most cases, it is something else—some other set of characteristics—that makes someone both happier and healthier. This distinction is tremendously important, because it affects what you should do to maintain and improve health. If you are clinically depressed, cognitive-behavioral therapy and anti-depressant pharmaceuticals can sometimes work wonders to get your life back on track. But you should not worry that the depression itself is wrecking your health.
Not many of us can (or would want to) live the Hollywood utopian ideal in which we spend all our days laughing with friends and loved ones while prancing through orchards and fields picking flowers and berries. Sometimes it is appropriate and healthy to be angry, sad, or disgusted.
Negative emotion is not cigarette smoke.
We as individuals have limited time—and our society, limited resources—to spend on health promotion and disease prevention. We need to understand the true causes of good health. The evidence is solid that social ties and physical activity are real causes of good health, but laughter merely a correlate. The science-based advice is to get out there and do things with others. If you do that, don’t worry about the laughter; it will take care of itself.
The Longevity Project, which explains the long-term pathways to thriving, was published in paperback edition by Plume (see http://www.howardsfriedman.com/longevityproject/) and is also available on Kindle and Nook. The book also contains self-assessment quizzes to help you figure your current trajectory.
Copyright © 2014 Howard S. Friedman, all rights reserved.
Photo of Blueberries in Hand By Seney Natural History (http://creativecommons.org/licenses/by-sa/2.0), via Wikimedia Commons: http://commons.wikimedia.org/wiki/File:Blueberries_in_Hand_%287686094500%29.jpg
