"Are Happier People Actually Healthier"
More than 60 years ago, the World Health Organization defined health
as a "state of complete physical, mental, and social well-being
and not merely the absence of disease or infirmity."
Just because you're not depressed doesn't necessarily mean you're happy.
But if you look in the medical literature, there are 20 times more studies
published on health and depression than there are on health and happiness.
In recent years, though, research on positive psychology has emerged --
what we can do to increase our success, functioning, and happiness,
all inherently good in themselves, but are happier people, healthier people?
There is growing evidence that positive psychological well-being
is associated with reduced risk of physical illness.
But it's not surprising that healthier people are happier than sick people.
The intriguing issue is whether psychological well-being protects
against future illness or inhibits the progression of chronic disease.
To figure out which came first, you'd have to get more than just a snapshot in time.
You'd need prospective studies, meaning studies that go forward in time,
to see if people start out happier do indeed live longer.
And, yes, a review of such studies suggests that positive psychological
well-being has a favorable effect
on survival in both healthy and diseased populations.
But not so fast.
Yes, positive states may be associated with less stress and inflammation,
and more resilience to infection, but positive well-being may also
be accompanied by a healthy lifestyle that itself reduces the risk of disease.
Happy people tend to smoke less, exercise more, drink less, and sleep better.
So maybe happiness leads to health only indirectly.
However, the apparent protective effect of positive psychological well-being
persisted even after controlling for all these healthy behaviors,
meaning effectively even at the same level of smoking, drinking,
exercise, and sleep, happier people did seem to live longer.
Ideally, to definitively establish cause-and-effect
we'd do an interventional trial in which participants are assigned
at random to different mood levels and tracked for health outcomes.
It's rarely feasible or ethical to randomly make some people's lives miserable
to see what happens, but if you pay people enough
you can do experiments like this. It's been thought that people
who typically report experiencing negative emotions are at greater risk
for disease, and those who typically report positive emotions are at less risk,
so they decided to test this using the common cold virus.
Three hundred thirty-four healthy volunteers were assessed
for how happy, pleased, and relaxed they were,
or how anxious, hostile, and depressed.
Subsequently, they were given nasal drops containing cold rhinoviruses
to see who would be more likely to come down with a cold.
Who would let someone drip viruses in their nose?
Someone paid $800, that's who.
Now just because you get exposed to a cold virus doesn't mean
you automatically get sick, because you have an immune system
that can fight it off, even if it's dripped right into your nose.
The question is whose immune system fights better?
In a third of the bummed out folks their immune systems failed
to fight off the virus and they came down with a cold,
but only about one in five got a cold in happy group.
Maybe it's because those with positive emotions slept better,
more exercise, lower stress? No, it appears even after controlling
for the healthy practices and levels of stress hormones,
happier people still appear to have healthier immune systems,
a greater resistance to developing the common cold.
Works with the flu, too. They repeated the study with the flu virus,
and like in the earlier study, increased positive emotions was associated
with decreased verified illness rates.
These results indicate that feeling vigorous, calm, and happy
may play a more important role in health than previously thought.