The recent rise of GLP-1 receptor agonists such as Wegovy and Mounjaro has brought major advances to obesity treatment. However, a rapid drop in body mass index (BMI) can be accompanied by structural changes in the skin and soft tissue. Drawing on 31 years of clinical experience in body contouring, this column examines the background of "Ozempic face" and body sagging that can follow rapid weight loss, along with the current evidence — and its limits — around regenerative strategies to address it.

1. Rapid fat cell shrinkage and changes in skin support structure

Fat is not merely a mass of tissue — it is a three-dimensional structure that helps support the skin. When medication causes fat cell volume to shrink rapidly over a short period, the extracellular matrix (ECM) beneath the dermis tends to lose elasticity, as it cannot keep pace with the rate of shrinkage. This tends to appear first in the face, often leading to hollowing beneath the cheekbones and deepening nasolabial folds — commonly referred to as "Ozempic face."

Surveys from professional societies abroad have reported a growing number of patients seeking treatment for aesthetic changes following GLP-1 medication use, along with a corresponding increase in facial fat grafting procedures. This appears to be less a matter of typical aging and more a case where the skin's support structure fails to adapt quickly enough to the pace of weight loss.

2. "Securing cells in advance" is not yet an established conclusion

Multiple studies note that the quality of transplanted cells is one important variable in planning regenerative procedures. However, the claim that "fat or stem cells harvested before starting a diet — that is, before weight loss — have greater regenerative capacity than those harvested afterward" diverges from the current body of research.

In fact, some studies report that adipose-derived stem cells harvested in an obese state show greater expression of inflammation-related factors and reduced mitochondrial function, with some of this function improving in cells harvested after weight loss. That said, other research indicates that cell characteristics do not fully return to a normal state even after weight loss, making it difficult to conclude definitively that "before is better" or "after is better."

In other words, no clinical study has directly compared transplant outcomes based on harvest timing (pre- vs. post-medication), and this remains an area where further evidence is needed.

3. The Line's approach to fat and stem cell processing

The Line applies a precise processing method designed to minimize cell damage during fat harvesting and processing, and manages tissue through its own storage system when needed.

That said, as noted above, it cannot be stated with certainty that harvesting and storing before medication produces better regenerative outcomes than harvesting afterward. The suitability of fat/stem cell storage and transplantation can vary depending on an individual's health status, rate of weight loss, and target area, so whether and when to proceed is best determined through individual consultation.

A Clinical note

"What matters more than the number on the scale is the density of your line."

Focusing solely on a lower number on the scale, at the expense of one's natural vitality, is hard to call true success. Successful weight loss is not just about achieving a thinner body — it is about completing a healthy silhouette while maintaining elasticity.

While material quality clearly matters in transplantation procedures, the notion that "pre-diet cells are simply the best material" has not yet been academically established. If you are considering — or have already started — a GLP-1 medication, it is advisable to discuss with a specialist which options may be suitable for you in preparing for the skin laxity that can follow rapid weight loss.

By Dr. Jaeho Cho (PhD in Surgery)