Sadly, these claims have been disproven by Snopes and deemed a money making or “clickbait” scheme. However, there are a couple of reasons why aluminum foil on the doorknob might be a good idea.
Being home alone often causes our minds to play tricks on us, hearing or seeing things that aren’t there. However, scary things happen, and we’re less equipped or more vulnerable when we’re home alone. For example, it has been suggested that putting aluminum foil on a door knob can help reduce your risk of intrusion, and there are several reasons why.
Purportedly, this makes it more difficult to grip the doorknob or pick the lock. Additionally, the aluminum foil will make a crinkle noise if someone is trying to get in, alerting you and giving you more time to respond.
Meanwhile, rubber bands were also recommended to help secure the aluminum foil to the door. Simply wrap a few around the handle after the foil has been securely wrapped around the doorknob.