All I know about cholesterol is that HDL should be high and LDL should be low. I don’t know what cholesterol actually does in your body. Is LDL low enough below some threshold, or is lower always better? Can LDL be too low? Also, what are triglycerides? And why isn’t the “total cholesterol” line on … Continue reading Optimal Cholesterol

In my last two posts on sleep, I reviewed the long-term health benefits of getting enough sleep and how you can get more if you don’t get enough already. In this final post on sleep, I’ll review tentative evidence about the possibility of going beyond just getting enough sleep, not by getting more sleep, but … Continue reading Sleep Part III: Competitive Sleeping

If you have disposable income, you have a moral obligation to give some significant fraction of it to people who have a lot less than you do. The moral imperative here is to make other people better off, not to make yourself feel warm and fuzzy. The corollary to the imperative to give, then, is … Continue reading Fork It Over

Now that I’m thoroughly convinced I’ll be healthier if I get at least seven hours of sleep a night, I want to maximize the quality of that sleep. For this post, I want to find experiments that put common sleep advice to the test. Call it 'Mythbusters: Sleep." I think some people get so obsessed … Continue reading Sleep Part II: How to Sleep Better

After posting about the natural experiment that showed everybody is more productive if everybody sleeps more together, I read the book Why We Sleep by Matthew Walker, a professor at UC Berkeley. It’s an exciting read and I decided to track down the original studies behind the parts of the book about living a longer … Continue reading Sleep Part I: Long-Term Health Benefits of Sleeping 7 Hours per Night

How can we know what food is healthy? Proving any causal relationship in nutrition is nearly impossible. I highly recommend this Freakonomics episode about how unreliable nutrition studies are. It’s not that the people studying nutrition aren’t smart, it’s just impractical to conduct the kinds of experiments we’d need to prove anything. What we need are … Continue reading Potato Chips Are the New Olive Oil

Most observational studies can’t separate correlation from causation, but one of my favorite Freakonomics episodes ever is about an observational study that used time zone boundaries as a natural experiment to estimate the causal effect of sleep on earnings. First, they note prior research that found a negative correlation between sleep and wages attributed to … Continue reading Always Be Sleeping