As you age, you will notice not only changes in your skin but also the accumulation of fat in various parts of your body. Fat accumulation in undesirable areas occurs gradually over time.
One of the most common areas this is seen is under the chin. Accumulation of adipose tissue under the chin, along with redistribution/sagging of the fat pads in the face can give you a very prominent double chin or “jowling” appearance. You do not have to be overweight for this to happen to you.