Whenever my son drops food on the floor, he wants to eat it. He tries to use the "5-second rule," saying food is safe to eat if it's picked up 5 seconds or less after it hits the floor. Is that true?
– Roslyn

No, it's never a good idea to eat food that has been dropped. The 5-second rule is just wishful thinking — bacteria can attach to food as soon as it hits the floor. And foods with wet surfaces, like an apple slice, pick up bacteria even more easily than things like a cookie.

Even food that's picked up quickly can be contaminated. Visibly dirty floors are obvious hazards, but those that look clean can harbor bacteria too. Some germs can survive on floors for a long time, and of course it's impossible to see them.

So what are you to do with that delicious piece of whatever that just slipped from your grasp? The safest choice is to throw it out.