And then he asked a question that all of us, at some point in our lives, should have thought to ask: “Why do they put directions on shampoo? I mean, if you don’t know how to wash your hair, should you really be standing naked under hot, running water by yourself?”

This newsletter, as Daily readers know, is dedicated to exploring the great disruption that’s happening in healthcare and medicine, and probing the ever-expanding science of well being. But there’s a dirty little secret it’s time to share: All of the new whiz-bang technology that inventors come up with—and all of the efforts to shape public health policy for the better—won’t amount to much if people don’t have the basic smarts and sense to take care of themselves.

Yesterday, as a case in point, the CDC released an update on the number of American middle and high schoolers who smoke or otherwise use tobacco. That number, happily, went down from 2015 to 2016 (mostly due to a decline in e-cigarette usage). But as the new FDA Commissioner, Scott Gottlieb, pointed out: That still leaves 3.9 million smoking, vaping, and hookah-sparking kids out there. (Not to mention a few weird pipe smokers in the chess club.) Every day, more than 400 young Americans “become daily cigarette smokers,” Gottlieb says.

As for basic smarts about food and nutrition, Americans seem to be starting from an even lower base. Witness a few telling data points that the Washington Post’s Caitlin Dewey scooped up yesterday as well. “Seven percent of all American adults believe that chocolate milk comes from brown cows,” she reported, citing a survey commissioned by the Innovation Center of U.S. Dairy. “If you do the math, that works out to 16.4 million misinformed, milk-drinking people,” Dewey said—or a population roughly the size of Pennsylvania’s.

Previous studies she cited found that rather large shares of teens (and, in some cases, adults) apparently don’t realize that onions and lettuce are plants, that hamburgers generally derive from cows, and that cheese is made from milk. (The full piece is well worth reading.)

All this said, there’s no doubt an ambitious young developer is hard at work on a technofix for this very problem: maybe a smartphone app you can point at a taco supreme and have it tell you exactly what’s in it—and whether it’s animal, vegetable, or mineral.

Until then, however, maybe we ought to do a better job of teaching the basics of health and wellness in fifth grade. And a little primer on shampooing wouldn’t hurt either.

This essay appears in today’s edition of the Fortune Brainstorm Health Daily. Get it delivered straight to your inbox.