How to get rid of chubby cheeks, lost face fat and make your Face Slimmer. “chubby cheeks” where the face is rounded and has a particular fullness to it. As the skin ages, the chubbiness turns into sagging tissue near one’s cheeks, jaw, and chin. Causes of Chubby Cheeks 1. Being overweight. 2. Lacking the necessary nutrients in your body. 3. High consumption of salt, sugar and carbs. 4. Water retention resulting from a bad choice of diet and constant dehydration. 5. Sleeplessness and high-stress