We all want healthy habits. But which healthy habits are actually healthy? Well, that’s a bit tougher to know.

Sure, exercise is good, and eating vegetables is good. Eating fewer processed foods is good, and eating more of them is bad. But when we get into the specifics, things get difficult. Maybe you’re jogging to lose weight, but someone tells you to stop – it’s hard on the knees, they say. Or maybe you’re eating kale because it’s a “superfood,” and someone tells you that “superfoods” are silly and don’t exist. Wait, what? Who is right?

Well, it’s hard to say who is technically right. Scientific knowledge on some of this stuff changes all of the time: sometimes diet sodas cause cancer, and other times they don’t, and sometimes kale is a miracle food, and sometimes it’s not. But we can say who is generally right, and it’s you – because you’re using your common sense. Diet soda may or may not cause cancer, but it doesn’t do anything good for you, and regular soda – with its tons calories – is definitively bad for you. And kale may or may not be “super” among foods, but it certainly isn’t bad for you, and eating leafy greens is always a good thing. When it comes to making good health decisions, common sense is what it’s all about.

Ah, naturally

Quick, what’s good for you: natural things or artificial things?

Your gut reaction is probably natural things, and that’s good! You’re right – usually. This is why we make decisions about our health based on common sense. It works.

Of course, you can point to plenty of inedible plants to prove that not all natural things are good for you. Don’t eat poison berries! And plenty of artificial things are great – you wouldn’t want to live in a world without penicillin. But with our common sense, we can see that natural is usually better. So when you have the choice to eat organic produce or choose a natural supplement over an artificial one, you know what to do: use your common sense.

Speaking of natural things, it’s nice that we’re finally living in a world where at least a few states have recognized the safety and benefits of marijuana, a natural drug. But here, too, we can use our common sense. What seems healthier – eating a plant or lighting it on fire and breathing the smoke? You probably guessed that cannabis edibles are safer than smoking marijuana, and there is some evidence that you may be right. At the very least, you’re certainly not increasing any risks by choosing edibles over smoking – so, once again, your common sense has won out.

Common sense and lifestyle choices

You can apply the simple common-sense rule to almost any decision about your health. Is running really bad for you? Well, this or that scientist may say so, but common sense will tell you the truth. Running does more good things than bad, and if it really does make your knees hurt at age 80 – well, then you can thank it for helping you live until 80, which you would probably not have done if you were fat! On the flip side, if your knees hurt every time you run right now, then common sense would dictate that you replace running with a low-impact activity like swimming. Common sense would probably not suggest that you stop running and replace it with nothing, because, well, then you’d get fat (or stay that way).

You can spend a lifetime learning the ins and outs of nutrition. Our data changes every day. Just look at diet soda: it was a miraculous soda that kept us thin, and then it was a terrifying potential source of cancer, and then it was not but maybe caused you to get a sweet tooth and drink more (regular) soda overall, and now it’s suspected that both natural and artificial sugars can aid the absorption of calories and make meals eaten with sodas unhealthier. That’s a lot of science and a lot of research. The common sense approach is simpler: this bubbling brown sweet drink that can dissolve teeth is perhaps not something you should drink a whole lot of.

In short, the common sense approach helps us approximate the benefits of a huge range of nutritional knowledge, without forcing us to constantly study up. It helps us stay on the best and simplest path to health. So remember: when in doubt, rely on your common sense!