I’ve been reading a lot lately about bacteria, both the kind that make us sick and the “good” kind that we need in (and on) our bodies to keep us healthy. It’s a fascinating topic, and one thing is certain: Bacteria (and other microbes as well) are not always the enemy.

When it comes to saying healthy, maintaining a proper balance of microbial life is probably as essential as eating five-a-day or exercising or not smoking–or any of the other things we spend so much time fussing about. The microscopic community that we think of as our bodies is in a delicate balance, and when that balance gets off, things often do not go well from our larger perspective. It is a very good idea to accommodate our resident “animalcules” (as Anton van Leeuwenhoek called microbes when he first spied them with his homemade microscope).

So the logical response is to eat yogurt, right? And kefir and all sorts of other foods fortified with probiotics? Well, that seems to be the conclusion reached by most health-related articles and books on this topic. I’m certainly not arguing with yogurt (or kefir either). It’s good stuff; it’s been around for centuries as a part of many traditional diets that seem to be quite healthful. It tastes awfully good, too (I just had a bowl of it for breakfast). Same with kefir and several other foods that contain various types of bacteria. They are good, sound, traditional foods.

But when it comes to all those “foods” that are fortified with this-and-that hard-to-pronounce bacteria and marketed as probiotics, essential for your health—that’s just the latest in supermarket hype, so take care. Keep in mind that balance is everything. Yogurt has been around forever, but the folks in lab coats only recently discovered which bacteria make it yogurt. They don’t know yet what microbes live within us and can’t yet say exactly what we need in there and what we don’t. Eat a good diet, and include yogurt and other such foods if you like them. But don’t let clever marketing cause you to stop eating food and start eating “products.”