Chewing gum strengthens the jaw muscles, leading to a more defined and sculpted face.

noli's read

Chewing gum actively engages the masticatory muscles, particularly the masseters. A randomized controlled trial (RCT) conducted by researcher Schimmel and his team confirms that chewing exercise measurably increases bite force and the thickness of these muscles. However, the idea that this will radically redraw facial contours to achieve a sculpted jawline is highly exaggerated. The visual definition of the jaw depends primarily on genetic bone structure and the distribution of adipose tissue, two factors that chewing does not influence. Furthermore, there are no observational or clinical studies directly linking gum chewing to aesthetic improvement of the lower face. On the contrary, excessive practice can overload the jaw joint and cause uncomfortable muscle tension in daily life.

the sources

No named source held this one up — that absence is part of the verdict.