Technically called microlipo injection, cosmetic fat injections are a popular procedure that involves removing excess fat from one area of the body and injecting it into another portion.
The main goal of the treatment is not to get rid of excess fat, but using the body’s own fat to increase the volume of sunken or creased skin. 
This is different from other procedures that involve injections, such as collagen and Botox.
The Procedure
Often, the treatment is done inside the doctor’s office under local anesthesia. Depending on the extent of the treatment, the procedure can last from 30 to 90 minutes.
First, antiseptic is applied to two areas: the portion where fat will be removed and the target area that will receive the fat injections. With a syringe or cannula (a thin hollow tube), fat cells are harvested from the buttocks, stomach, or thighs.
Once the fat cells are suctioned, they are processed and purified so that no foreign materials that may pose risks can be included in the transfer. The fat is then injected beneath the skin into the treatment area.
While results can be evident right after the operation, it’s important to know that the effects are temporary because transplanted fat cells will die without blood supply in three to four days. The transferred fat may also be reabsorbed by the body, thus undergoing this treatment may be a gamble.
Enhancing the Face
Fat injections have worked well for augmenting lips, removing laughter and frown lines, and plumping up hollow cheeks.
Facial fat injections are done in thin layers starting behind the muscle groups and then working forward. After the initial fat transfer, patients are then encouraged to have several more treatments over the next couple of months because of the natural absorption of the transferred fat. The recovery period is relatively short and the fat donor area is mostly the only place where there will be swelling and bruising.
As for lip augmentation, tiny, punch-like incisions are made at one corner of the patient’s mouth. The surgeon then uses one to two millimeters of fat cells and gently works them into the upper and lower lips for a plumping effect.
Fat Transfer vs Dermal Fillers: Which Is Better?
One common question is whether fat transfer or dermal fillers like Juvederm® or Restylane® are better for facial volume restoration. Both have their advantages—fillers offer convenience and predictability, while fat injections use the body’s natural tissue, making them less likely to trigger allergic reactions.
Additionally, fat transfer may last longer than synthetic fillers and is often more cost-effective over time for patients needing larger volume correction. However, fat grafting requires a more complex procedure and carries the risk that a percentage of the transferred fat may be reabsorbed by the body.
Buttock Augmentation Through Fat Transfer
Patients who can spare some fat deposits in their body can also choose fat injections to increase the size of their buttocks. This procedure is more commonly called the Brazilian butt lift.
Here, the surgeon places fat cells at dozens of levels to the patient’s rear. In most cases, the procedure limits physical activities a patient can make.
Ideal Candidates
Not all patients are good candidates for this treatment. The ideal candidate is considered to be someone in good health and does not smoke.
They should also be able to comply with aftercare instructions and be prepared for multiple sessions. In addition, patients must have excess fat in various parts of the body. Otherwise, another type of cosmetic plastic surgery may be performed instead.
Advantages
The possible complications involved in fat injections are typically minimal. The fat is gathered from the patient’s own body, so there is no risk of the body rejecting the transplant. The results are also instantaneous and do not last for a long time, so patients always have control over their looks.
How Long Do Fat Injections Last?
Although results from cosmetic fat injections can be seen immediately, their longevity depends on several factors, including technique, patient metabolism, and lifestyle habits. In many cases, 30% to 50% of the injected fat is reabsorbed within the first few months.
However, the fat that survives and develops a new blood supply can remain in place for several years. This is why doctors often recommend multiple sessions to build lasting volume gradually. Following post-procedure instructions and maintaining a stable body weight can help prolong results.