Fat transfer, also called autologous fat grafting, is a surgical procedure that moves fat from one part of your body to another. Fat is harvested through liposuction from an area where you have excess (commonly the abdomen, thighs, or flanks), processed to isolate healthy fat cells, then injected into an area that needs volume. It’s used for both cosmetic and reconstructive purposes, and because the material comes from your own body, it doesn’t trigger an immune response.
How Fat Transfer Works
The procedure happens in three stages: harvesting, processing, and injection. During harvesting, a surgeon uses liposuction to remove fat from a donor site. The collected fat then goes through a purification step to separate viable fat cells from blood, oil, and damaged tissue. Finally, the purified fat is injected in small amounts into the target area using fine cannulas.
Several processing methods exist, including spinning the fat in a centrifuge, filtering it, rolling it on absorbent gauze, or simply letting gravity separate the layers. Centrifugation concentrates the stem cells and progenitor cells within the fat, which may improve long-term graft survival, but spinning too aggressively can damage the fat cells. Gentler methods like filtration and gauze rolling cause less trauma to the tissue. No single processing technique has proven clearly superior to the others.
Once injected, the transferred fat survives through a two-phase process. First, the fat cells absorb oxygen and nutrients from surrounding tissue through simple diffusion, similar to how a transplanted plant draws moisture from new soil before its roots take hold. Cells on the outer edges of the graft survive well during this phase, while cells deeper in the center often die off. In the second phase, new blood vessels grow into the graft, a process that determines how much fat ultimately survives. The body sends stem cells and inflammatory signals to build this new blood supply, and once it’s established, the graft becomes living, integrated tissue.
How Much Fat Survives
Not all transferred fat makes it. Survival rates range from about 30% to 83%, depending on the technique used, the area treated, and individual biology. For breast procedures, published survival rates fall between 34% and 82%. Facial fat grafting shows a similar range of 30% to 83%. A commonly cited clinical expectation is that roughly 70% of transferred fat remains intact after the initial settling period.
This variability is one reason fat transfer sometimes requires more than one session. Surgeons often plan for some degree of reabsorption and may slightly overfill the treatment area to compensate, or schedule a follow-up procedure several months later to refine the result.
Where Fat Transfer Is Used
The procedure has a wide range of applications across both cosmetic and reconstructive surgery.
- Face: Restoring volume lost to aging in the cheeks, temples, under-eye hollows, and around the mouth. Much of facial aging comes from fat tissue shrinking beneath the skin, so replacing fat directly addresses the underlying cause rather than just filling wrinkles.
- Breasts: Used for primary augmentation, correcting asymmetry, and recontouring after cancer surgery. Volumes typically range from 100 to 300 mL per breast in a standard session, though some surgeons inject 300 to 600 mL or more depending on the patient’s anatomy and goals.
- Buttocks: Often called a Brazilian butt lift, gluteal augmentation with fat transfer avoids implant-related complications like capsular contracture, migration, or implant exposure.
- Hands: Replacing volume loss on the backs of the hands, where thinning tissue makes veins and tendons more visible with age. Fat transfer here improves both volume and skin quality.
- Scars and deformities: Fat grafting has been used to treat burn scar contractures, post-traumatic scars, and congenital conditions. The regenerative properties of the stem cells within fat tissue can improve skin quality and texture beyond what simple volume filling achieves.
Fat Transfer vs. Dermal Fillers
For facial rejuvenation, the main alternative to fat transfer is injectable fillers made from hyaluronic acid or similar manufactured materials. Fillers are done in an office visit with minimal downtime and work well for early-stage volume loss, which is why they’re the go-to option for many people starting in their 30s. Results from fillers typically last up to two years before the material is absorbed and the treatment needs repeating.
Fat transfer is more involved. It requires liposuction, a surgical setting, and a longer recovery. But the fat itself is essentially free to obtain (you already have it), and results that survive the initial settling phase can last for many years. The tradeoff is that fat grafting is more technically demanding and less predictable in terms of exactly how much volume will remain. For larger areas like the breasts or buttocks, fillers aren’t practical, making fat transfer the clear choice.
Recovery Timeline
Recovery involves healing at both the donor site (where fat was removed) and the treatment area (where it was injected). You can expect swelling, bruising, and soreness at both locations in the first week. By one to two weeks, these symptoms are noticeably improving, and most people with desk jobs can return to work. By two to three weeks, you can generally resume all regular activities, including exercise. Incision sites may still appear red but should be healed, and any residual bruising on the face can be covered with makeup.
The results you see immediately after the procedure aren’t final. Swelling distorts the appearance in the early weeks, and some of the transferred fat will be reabsorbed over the following months. It generally takes about six months to see your true, settled result. After that point, the fat that has survived and developed its own blood supply is considered permanent, though it will age naturally along with the rest of your body.
Risks and Complications
Fat transfer is generally considered safe, but it carries the risks inherent to any surgical procedure, including infection and seroma (fluid buildup). The complication most specific to fat grafting is fat necrosis, where transferred fat cells die and form firm lumps or oil-filled cysts under the skin. This occurs in roughly 2% to 18% of procedures. In one study of breast fat grafting patients, 23% developed a palpable mass at a median of 10 months after the procedure. Most of these turned out to be benign fat necrosis or oil cysts, though a small number required biopsy to rule out other causes.
Fat necrosis lumps can sometimes be left alone if they’re not bothersome, or they can be drained or surgically removed. In the context of breast procedures, these lumps can show up on mammograms and require additional imaging to distinguish them from concerning findings, which is worth knowing if you’re considering breast fat transfer.
The most serious risk associated with fat transfer, particularly in buttock augmentation, is fat embolism, where fat enters a blood vessel and travels to the lungs. This is rare but potentially life-threatening, and it’s the reason buttock fat grafting carries stricter safety guidelines around injection depth and technique.
Who Is a Good Candidate
The basic requirement is straightforward: you need enough excess fat to harvest. A surgeon will evaluate your abdomen, flanks, and other potential donor sites to determine whether there’s sufficient material. Very lean individuals may not have enough fat to achieve meaningful results, particularly for larger-volume procedures like breast or buttock augmentation.
Ideal candidates are in good overall health and at a stable weight, with a BMI of 30 or less to reduce the chance of surgical complications. Weight stability matters because the transferred fat behaves like fat anywhere else in your body. If you gain weight after the procedure, the grafted area can enlarge. If you lose significant weight, you may lose some of the transferred volume along with it.