How Does Fat Transfer Work?

Episode summary

Fat transfer moves a patient's own fat from a donor area to another part of the body to add or refine volume. Because the transferred tissue must establish a blood supply, not all of it necessarily survives. New York City board-certified plastic surgeon Darren M. Smith, MD, FACS explains what this means for planning and expectations.

Originally published July 14, 2020. Techniques, prices, and outcome estimates discussed are historical examples, not current quotes or guarantees.

Key takeaways

🔬 The graft is living tissue.

Dr. Smith explains how transplanted fat initially depends on the surrounding tissue before developing a blood supply.

🔎 Harvesting and placement are distinct steps.

The episode describes obtaining fat with liposuction, preparing it, and placing it in a recipient area.

🔬 Fat transfer has several uses.

Examples include facial volume, breast reconstruction, breast augmentation, and selected combinations with other operations.

🔎 Retention is variable.

Some fat can be absorbed, and another procedure may be considered after the result settles.

🔎 The intended volume change matters.

Dr. Smith discusses donor-fat availability and why fat transfer alone may not match the goals of someone seeking a large breast-size increase.

Questions this episode answers

Will all transferred fat remain?

No. The recording emphasizes that survival is incomplete and variable, which affects the eventual volume and symmetry. Its numerical retention estimates should not be treated as a personalized forecast.

Can fat transfer replace breast implants?

It can be considered for selected volume and contour goals, but the episode describes limits related to available donor fat and the amount retained. Dr. Smith also discusses combining an implant with fat transfer to refine particular areas of the breast.

Why is a BBL discussed separately?

The episode highlights the distinctive risks of gluteal fat grafting, including fat embolism. Current context: the 2022 multisociety safety statement supports real-time ultrasound guidance to help keep fat placement above the gluteal muscle fascia. This does not eliminate risk. Read the ASPS joint safety statement alongside this archival discussion.

🔗 Related reading and consultation

Facial fat grafting | Fat-transfer breast augmentation | Request a consultation

Educational information; suitability, retention, recovery, and risk vary. Show notes updated September 30, 2026.

Original show notes

Fat is a funny thing. Sometimes we can't stand it, but sometimes it is the key to achieving stunning aesthetic results. Fat transfer expert and board certified NYC plastic surgeon Dr. Darren Smith dives in.

[00:08] I'm board certified New York City plastic surgeon, Dr. Darren Smith, and this is plastic surgery before and after. Your source for the real deal about plastic surgery procedures, news about trends in aesthetic medicine, and candid sessions with industry insiders. We hope you enjoy today's episode. How does fat grafting work? Well, let's back up for a second and talk about what fat grafting or fat transfer actually is. So fat grafting is the process by which we harvest fat from one part of the body and use it in another part of the body. Now this is essentially a form of cellular transplantation, meaning we're taking tissue from one part of the body, in this case it's fatty tissue or adipose cells, and repurposing it to serve a function elsewhere in the body.

[01:02] And the difference between fat transfer and what you might kind of classically think of as organ transplantation, like a kidney transplant or a liver transplant, is that with those operations, you are taking a kidney and its blood vessel and hooking that blood vessel up to the blood vessel at the recipient site so that blood can pump from the recipient site into the end organ, in that case, the kidney. Whereas in a fat graft or a fat transfer, you're not hooking up any blood vessels. You're dealing with individual cells. So initially, we are relying on the environment of those cells to be able to provide the same services as blood vessels. So we need those cells to get oxygen from their environment and we need them to be able to get rid of waste products without the direct connection of a blood supply. So they do that.

[01:57] by essentially releasing waste products into their environment and taking in the nutrients and oxygen that they need from their environment for the first several days after they're transplanted. And ultimately, new blood vessels do grow into these cells and they start to function like many organ transplants once they do have an independent blood supply. So sorry for getting into the weeds there with the science, but all of this is to say that fat transfer or fat grafting is essentially a form of cellular transplantation from one part of the body to another. And fat transfer or fat grafting has had all kinds of uses. It's very popular in breast reconstruction. If we need a little more volume in the reconstructed breasts, we simply harvest that from one part of the body and add it to the breasts to make them a little more of a luminous or to improve their shape. We can use similar strategies in breast augmentation either to.

[03:03] enhance the appearance of a breast implant based breast augmentation or to do a breast augmentation with fat grafting or fat transfer on its own. Both of those things are fairly popular now. One of my favorite uses for fat grafts is in facial rejuvenation and we can use fat to rejuvenate the face in several different ways. One of the main things that leads to the classic appearances of facial aging is the loss of facial volume. So Instead of using fillers to increase facial volume and improve facial structure, we can actually use fat grafts and transfer fat from elsewhere in the body to the face to create a more youthful appearance. We can also use fat grafting for facial rejuvenation in combination with a facelift. So where a facelift is excellent for dealing with skin laxity and we can reposition the deeper tissues of the face, there is a limit.

[04:00] to how much volume change and volume repositioning we can do with a facelift because if you've already lost a lot of fat from your face, you can't create that fat from nowhere. Whereas with fat grafting, you have a whole new kind of flexibility. So you can reposition the facial foundation with the facelift. You can redrape the skin to be exactly where you'd like it to be, to have a nice youthful contour. But now you have this really great source of volume in the form of fat from elsewhere in the body and we can do fat grafting at the same time as a facelift to both build that foundation and also increase facial volume, build a really nice youthful appearance. So in terms of the nitty gritty of how does fat transfer work or how does fat grafting work, we perform liposuction from what we refer to as the donor site, which is the area that we're going to grab those fat grafts from. So that's often the abdomen or the waist or the inner thigh or anywhere with a little extra bulk that you'd like us to steal. And we can often do that very gently. We don't need the power assisted liposuction for this. And we can often do it with a tiny incision, you know, often smaller than the size of a pencil eraser. So the fat is gently harvested causing almost no discomfort.

[05:16] we then process that fat. And when I say process the fat, the goal here is to make the fat into a paste that will have a very small particle size so that it easily glides into the donor area. And it can have accessibility to all those nutrients that we were talking about earlier without being caught in big clumps of fat. And we do this by passing the fat in syringes through a device that essentially exposes the fat to smaller and smaller diameter channels. So these are almost like funnels that have progressively smaller diameters. So in order to get through the fat particles have to get smaller and smaller and over time by doing multiple passes like this we form that fat graft into a nice uniform smooth paste for fat transfer into the donor site.

[06:09] And after we've done this and we've gotten out the extra oils and other fluid that we don't necessarily want as part of our fat graft, and we do this by gently rolling the fat graft over special absorbent pads, we take that fat, load it into very small syringes, and we fit those syringes with very small diameter fine cannulas, which are blunt tipped, and they have the lumen or the hole off to the side. So this provides a very safe comfortable injection experience. And we then simply deposit these processed fat grafts into the recipient site. And depending on the area that we're targeting with these fat grafts, we're using extremely fine cannulas and the access points to insert these cannulas are often made with a needle. So there is really often no visible score at all at the recipient site for a fat graft. And once that fat graft has been placed, it's essentially a waiting game.

[07:08] we need to provide an optimal environment for those fat grafts, those individual fat cells or adipocytes to be able to take on nutrients from their environment like we were speaking about earlier until new blood vessels grow to supply them directly. And the key to doing this well is to again be using a very small fat particle size and placing only very small quantities of fat with each pass of the cannula to ensure that it's exposed to the largest surface area possible of surrounding tissue so that it can on the one hand take in as much oxygen and nutrients as it needs and also on the other hand get rid of as much waste as it has to until it has its own dedicated blood supply. And because these fat transfer these or these fat grafts are essentially cell transplants or tissue transplants, it's not guaranteed that all of the fat that we transfer is going to survive. In fact, in most cases and in most locations, we say that about 50 to 60% of the fat that we transfer on average is going to survive permanently. So in a lot of instances, we'll end up deliberately overgrafting or overfilling the recipient area. So we get the result that we're looking for once that fat does partially resorb. So fat grafting is a very dynamic process, and what we like to say is that by about six months after the procedure for fat transplantation or fat grafting, that's when you can really get a sense of what the final result will be like. So no matter how much fat you're putting in, you're gonna lose the percentage of it, like we mentioned about...

[08:47] you know, 40 to 50 percent isn't going to make it. And by the time you get to about six months, you have a good sense of what that final result is going to look like. And we often go into fat grafting procedures with the expectation that we're going to have to do a second round of fat transfer after, you know, six months or so, so that we have the flexibility to evaluate the result and then add a little extra fat here or there to tweak things and really get it perfect. I didn't mention, you know, one of the really most popular kinds of fat transfer that's done right now when I was speaking about where we're doing fat transfer a little earlier in the episode, because this kind of fat grafting really kind of stands on its own as its own procedure. And that is fat transfer to the buttocks or the Brazilian buttock lift or BBL.

[09:36] And this is where we're taking fat from elsewhere in the body, often large volumes of fat from the abdomen or the waist or the flanks, and we're then transferring it to the buttocks. And this is different because this is a very large, often volume of fat transfer. And the goal here is to improve the shape or the size of the buttocks or their projection or their perkiness. And while the same principles do hold here for Brazilian buttock lift or BBL, as with the other kinds of fat transfer we were discussing earlier, it deserves to be singled out and highlighted because this is a procedure that is actually a lot more dangerous than a lot of other aesthetic surgery procedures, including other kinds of fat grafting procedures. And the reasons for this aren't completely understood.

[10:28] But part of the issue is that there are very large blood vessels in the buttocks and when large volumes of fat are injected into the buttocks this can cause a fairly steep pressure gradient or put a lot of pressure on the buttocks and that can force fat into those large blood vessels in the buttocks which can then travel to the heart and be very dangerous even lethal in the form of what's called a fat embolism. A fat embolism is when fat gets into the circulatory system and cuts off blood supply to other parts of the body. So the Brazilian buttock lift or BBL or fat transfer to the buttocks is kind of a unique procedure in that its risk profile is much higher than the risk for fat grafting to other parts of the body or other cosmetic surgery procedures in general. So it just deserves to be mentioned on its own and you know when you are considering having this procedure it's especially important to go to a board certified plastic surgeon who has real expertise in fat grafting and a proven safety track record specifically with this procedure. The other question we frequently get with regards to fat transfer is how much does fat transfer cost or how much does fat grafting cost and this is something that varies a great deal and as we've discussed with other procedures the factors that come into play here is the experience level of your surgeon the geography of where you're having your procedure performed, the volume of fat that you're having transferred, the location of the fat that you're having it transferred to, and the overall complexity of the procedure. But to make things simple by way of comparison, I think it's reasonable to expect to pay in Manhattan, and that's what I'll use for reference because I have a New York City-based plastic surgery practice.

[12:22] for a focused area of fat grafting. Let's say somebody wants to use fat grafting to augment their cheeks and the procedure is done under local anesthesia. That's something that I think you can reasonably expect to pay anywhere from $3,000 to $6,000 for, again, depending on the experience level of your surgeon. Another area that I'd like to touch on specifically here is fat grafting through the breasts. And this is a topic that requires special mention because the breasts obviously are usually a paired structure, meaning you have a right breast and a left breast. And we've previously mentioned that we don't know for sure how much fat is going to survive with a given fat grafting procedure. So if we're using fat to augment the breasts, it follows that we can't be sure that even if we put the same amount of fat on both sides, we're going to have the same amount of fat permanently survive in each breast. So to make sure we get good symmetry, you really need to go into one of these fat grafting procedures to the breasts with an open mind to having a secondary fat grafting procedure.

[13:31] The other thing to know about fat grafting to the breast is that while it's very appealing in a lot of ways to look at fat grafting as a primary way to do breast augmentation, you know, maybe you don't need a breast implant if you're using fat, it really takes a significant amount of fat to increase your breast size as much as you might like to. So as a framework for reference, we usually say that to increase the breasts by a cup size you have to increase the volume of the breast by 100 to 150 cc or milliliters and that is a significant amount of fat. For example in a standard liposuction case of the abdomen I'm usually taking between 600 cc or milliliters and a liter of fat from the abdomen.

[14:25] and after processing about half of that fat is actually useful for transplantation so if we're taking you know at most a liter of fat out of the abdomen during a liposuction procedure we're going to have about 500 cc or 500 ml of usable fat for fat grafting. And assuming we're going to be grafting the breasts pretty much symmetrically, that gives us 250 cc or 250 ml per side of fat. And then if we remember that we said that about half of that fat on average is going to last in a permanent way. that means that just 125 cc of fat is going to last in a meaningful way. So in a standard liposuction case where we're taking a significant volume of fat from the abdomen, that's about a liter, we're going to end up with about 125 cc of fat that's going to stick around on each side. And if you recall, on average, that to go up an entire cup size, we need between 100 and 150 cc of fat.

[15:31] That means that for this fat grafting procedure where we're taking a fairly hefty amount of fat from the stomach, a whole liter, we're only going to be able to go up a cup size. So again, the fat transfer method when used in isolation for breast augmentation might be okay for those that want a modest improvement. But if you're looking to go up significantly in your breast size, for the most part, you should really be looking at an implant-based breast augmentation, which can certainly be augmented by a fat graft if you want to manipulate specific aspects of the breast shape. For example, sometimes people will have an implant-based breast augmentation and then have fat grafting to the upper pole of their breasts to really kind of highlight that fullness. But fat transfer on its own may not be the best approach to a breast augmentation if you're looking for a really large increase in breast volume. So there you have it. That is more or less the skinny on fat transfer or fat grafting.

[16:34] And we hope that that's kind of explained how fat grafting works, specifically fat grafting for breast augmentation and fat grafting for facial rejuvenation or facial volume, and also fat grafting to the buttocks in the form of a Brazilian buttock lift. So fat grafting is a very powerful procedure, but we really have to kind of understand the nuances to make sure that we're delivering the optimal results that you want to be seeing. Thanks for listening, and don't forget to subscribe, share the show, and head over to DarrenSmithMD.com for more real-world plastic surgery talk.

Original Captivate episode. Original release date: 2020-07-14. The recording is the source for the transcript and episode discussion. Later context in the written summary is identified separately.

• Facial fat grafting
• Fat-transfer breast augmentation
• Request a consultation
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• Dr. Smith’s background and training