Let's say you'd like to be healthier but you're overwhelmed by reading all of the conflicting magazine articles and books regarding what's the healthiest way to eat, exercise, improve your sleep, avoid toxins, boost your immunity, have better sex, prevent damage to skin and eyes and ears and whatnot, and feel secure in definitive answers.
Yeah, good luck with that.
A. J. Jacobs has made a career out of experimenting with his life -- he read the Encyclopedia Britannica for a year, he lived by (Old and New Testament) Biblical principles for a year, he did a bunch of mini-experiments, and now, he's spent two years trying to improve his health by interviewing experts and living by their advice. Mixed in are tiny anecdotes regarding his grandfather (who would have made a wonderful subject of a book), his long-suffering wife, and his little boys. Considering he's an editor at Esquire, you'd expect a few juicy work stories, but nope.
Jacobs is workmanlike; each chapter is a bit like a blog post -- a concentration on one health area with a few sub-areas and a round-up of his monthly progress. It's lightly self-deprecating, and certainly easy enough to read. At times, it's a relief that Jacobs is going to all of this effort, because it sounds exhausting, and at times depressing. And still, very little is definitive.
The problem is that science can lack certainty, so some of what Jacobs conveys is the certitude with which some experts speak and the conflicting nature of so-called experts on the same topics. He (mostly) treats out-there wackadoodles with respect, but late in the book, I found that he interviewed a man I know personally to be abusive and to have fabricated the accuracy and recency of his credentials, which makes me call into question everyone else interviewed.
So, if you like reading about people doing life experiments (as I do), this may be up your alley. You may find Jacobs annoying, which, after 300+ pages he can be, and you'll have to decide for yourself which approaches will work (or at least work for you), but it's well-written and, at worse, benign.
Warning, a few of the personal anecdotes are sad; if you're in mourning, you may want to move this to the bottom of your pile.
Finally, Jacobs does provide some great resources in case readers want to follow up on their own. So, you may not get certitude, but you may find some inspiration and options.