Dreaming about obesity or a sudden change in your size is very common. It often suggests that you are not comfortable with the look that you present to the world. If you are extremely obese in your dream, the message could be that you are overindulging in an area of your life that you need to scale back on. You may also be trying to put a few layers of insulation around your personality for other reasons.
For example you may be trying to shield yourself from hurt from someone in your life. Or you may be putting up a guard for other reasons. If you are obese and dream of this symbol, the message could be showing you ways to get yourself out of this situation. If you are very skinny and experience this in your dream, the message is that your health may be impaired if you do not attempt to put more weight on. Low self-esteem may be the message as well if you dream of being obese, and are unsure of the reason why.