[enraged_camel]

Why do I need to know why laughter improves my health? This is a serious question. Do people laugh because humor helps cope with stress, which leads to better immune systems, reduced risk of heart attack and stroke, less pain during dental work and a longer life? Or do they laugh because they find something funny? I would posit that there is not a single person who read that blog post and thought "gee, I should laugh more often because it has all these health benefits!"

Perhaps that's the problem with the post in general: it is not practical. For example, instead of (or in addition to) saying that exercise is good for you, it could say "here are some exercise programs for beginners" and post links to P90X or Couch-to-5K. That way, the post could become a useful resource for people who actually want to improve their life, rather than a regurgitation of commonly-known facts.

[gknoy]

Having an explanation of why helps our bullshit detector, and lets us re-evaluate claims if the explanation's basis falters later. If someone says, "X is bad for you because of Y", that may sound plausible. If they say that "Study Z shows that X causes Y, so don't do X", it's VERY much more plausible.

More importantly, if study Z turns out to be a hoax, we can look at the claims that used that as their basis and re-evaluate them.

You make a pretty good point about ways to make the blog posts more useful, though.

[kscaldef]

    Why do I need to know why laughter improves my health? 

Because otherwise someone else on HN will say: "citation needed!"

[Cl4rity]

As another commenter says, it helps the bullshit detector. Why know why anything works? If we just follow advice blindly, it may do us no good.

Your line of questioning is all wrong. You said, "I would posit that there is not a single person who read that blog post and thought 'gee, I should laugh more often because it has all these health benefits!'"

Therein lies the flaw in your thinking. You don't read something like this and think you should laugh more just for the sake of laughing and its health benefits. Instead, you'd read something like that, understand WHY laughter has those benefits, and then make an effort to put yourself in situations where you'd be more relaxed and open to laughter, like hanging out with funny friends or taking a date to a comedy club.

In fact, you answered your own question: Why do we need to know why laughter improves health? Is it because laughter helps cope with stress?

BOOM. You answered your question.

Maybe that's one of the reasons, but if you dig deeper, maybe there are more. Then once you begin to understand how and why certain behaviors and situations affect our lives, you can adjust accordingly. Maybe you don't need to laugh all the time if you understand that laughter is primarily a coping or stress-reduction mechanism. Maybe you can go do other activities that have the same effects.

You need to think about this stuff differently.