There's one study that suggested a half-hour of regular cardio exercise every day can be as effective as a prescription of Zoloft for improving your mental health.

One famous study had subjects get normal sleep for two days, then deprived sleep for a week (deprived wasn't zero hours of hours of sleep, it was five hours of sleep), and then you go back to normal sleep. And what you find is that, during that week of deprived sleep, subjects' mental health tanks—almost to the point that it looks like their mood levels had hit clinical depression.

Our phones are an incredible distractor ... Your brain could be paying attention to the dinner you're having with a friend of yours, or it knows that on the other side of that phone is every baseball statistic ever invented, the contents of every album and museum in the world, every political quote, every tweet, porn, cat videos. Your brain knows that there's a really exciting alternative that it could be paying attention to at anytime.

If you stick people, say, in a waiting room, and you give them access to their cell phones, even if they're not necessarily using them, they smile at the people around them 30% less than if they didn't have their cell phones around them.

One of my favorite famous studies on social comparison actually looked at Olympic athletes and Olympic medal winners. And what they did was they looked at who's the happiest on the Olympic medal stand. And what they find, which is surprising, is the person who wins the bronze is actually much, much happier than the person who wins the silver.

The act of scribbling down 3-5 things you're grateful for can significantly improve your well-being in as little as two weeks.

There's also evidence that exercise can have a long-standing effect on your well-being. So, you do, say, a half-hour of cardio Monday morning, the data suggests that little bump in endorphins... that will still be there with you, if you do it Monday at 9 AM, until around Tuesday at, like, 1 PM.

If you look at those spiking rates of depression and anxiety, the kink in the curve of these things going up seems to happen around the same time that the iPhone was introduced and started to go viral.

There is definitely a genetic component to happiness, but it's much smaller than we think. In terms of what's called heritability.... it seems like heritability is around 40% for happiness.

One statistic suggests that among college-aged folks... we've seen depression double in the last nine years.