Being thin does not automatically mean that you are not a candidate for submental liposuction. Some people are naturally predisposed to keeping a small pocket of fat underneath the chin even when they have very little body fat elsewhere. Liposuction is specifically intended to address localized fat deposits that don't respond to weight loss or exercise. That said, in someone who is already quite lean and has only a small amount of fullness, I would be very conservative. The question isn't simply, “Can I remove this fat?” but rather, “Is there enough fat to remove that the improvement will justify the risks of the procedure?” Your recessed chin is an important part of the picture You mentioned that your chin is somewhat recessed and that the fullness underneath it makes that more noticeable. That's an important observation. A relatively small or recessed chin can make the area underneath the chin look fuller even when there isn't much actual fat. In some patients, improving the projection of the chin can create a stronger jawline and a better chin-to-neck transition without needing to remove much fat. Chin position and submental fullness are often evaluated together when planning facial contouring. So I wouldn't automatically assume that liposuction alone is the best answer. Could a small amount of liposuction help? Yes, potentially. If there is a discrete, pinchable pocket of subcutaneous fat and you have good skin elasticity, very conservative submental liposuction can be effective even in a thin person. The key is avoiding over-treatment. Removing too much fat from an already lean face can create contour irregularities or make the skin look less supported. Skin elasticity is an important part of determining how well the area will contract after liposuction. And because your concern seems relatively subtle, I would much rather see a small improvement with a natural contour than try to completely eliminate every bit of fullness. What if the fat pocket is too small for lipo? There are nonsurgical options for small amounts of submental fat, including deoxycholic acid injections such as Kybella. However, these aren't automatically better just because they don't involve surgery. They can cause significant swelling and generally work best in patients with a clearly defined, mild-to-moderate amount of fat and reasonably good skin tone. In a very thin person with a small amount of fat, I would be particularly cautious about trying to treat a tiny area repeatedly if the actual issue is primarily chin projection rather than fat. Your “thumb test” is actually interesting The fact that you can improve the appearance substantially by gently pushing the tissue upward suggests that the contour is influenced by the soft tissue beneath the chin, but it doesn't tell us exactly how much of that tissue is fat versus skin, muscle, or the underlying chin anatomy. That's why photographs alone can be misleading. The most useful assessment would be looking at your profile and three-quarter views, feeling the thickness of the submental tissue, and evaluating your chin projection and neck angle together. If your chin is genuinely recessed, even a modest improvement in chin projection can sometimes make the neck look cleaner and the chin look more defined. My overall thought Based on your description, I wouldn't rule you out for very conservative chin liposuction simply because you're 5'4" and 120 pounds. Your weight itself isn't the issue. What would make me cautious is the combination of very little fat + a somewhat recessed chin. In that situation, I would want to be certain that the fullness you're seeing is actually fat that can be meaningfully reduced, rather than trying to liposuction away a contour that is primarily related to your skeletal anatomy. Sometimes the best result comes from treating the relationship between the chin and the neck, rather than focusing exclusively on removing fat. And importantly, you don't need to have a dramatic “double chin” to benefit from subtle contouring—but the improvement should be realistic and proportional to what is actually there.