A Brazilian Butt Lift, or BBL, is made entirely of your own body fat. Unlike implants made from silicone or other synthetic materials, a BBL uses fat harvested from elsewhere on your body through liposuction, then purified and injected into your buttocks. It’s a fat transfer procedure, which means the only material being added to your body is tissue you already have.
Where the Fat Comes From
The fat used in a BBL is harvested from areas where you naturally carry excess. The abdomen is the most common donor site because it tends to hold the highest volume of soft, graftable fat. The flanks (love handles), lower and mid-back, and thighs are also frequently used. For leaner patients, surgeons may pull from smaller deposits in the upper thighs or even the arms.
The choice of donor site depends on your body type, fat distribution, and skin quality. Previous surgeries or scar tissue in an area can reduce the amount of usable fat. Surgeons also factor in the cosmetic benefit of removing fat from a given spot, since the liposuction itself reshapes your silhouette. This dual sculpting effect is part of what makes the BBL popular: you lose volume where you don’t want it and gain it where you do.
How the Fat Is Harvested
Before liposuction begins, the surgeon injects a solution called tumescent fluid into the donor area. This is a mix of saline (sterile saltwater), a local anesthetic to numb the tissue, a small amount of adrenaline to constrict blood vessels and reduce bleeding, and sodium bicarbonate to buffer the acidity. The fluid swells the fat layer, making it easier to remove while minimizing blood loss and bruising.
A thin tube called a cannula is then inserted through small incisions to suction out the fat. Gentle harvesting techniques help keep the fat cells intact, which is critical because damaged cells won’t survive after transfer.
How the Fat Is Purified
Raw liposuction aspirate isn’t pure fat. It contains blood, tumescent fluid, oil from broken fat cells, and other debris. Before injection, this mixture needs to be cleaned so that only healthy, intact fat cells are reintroduced to the body.
The most widely used method is centrifugation, where the harvested material is spun at controlled speed to separate viable fat cells from everything else. The heavier blood and fluid settle to the bottom, the oil from ruptured cells floats to the top, and the usable fat collects in the middle. Other surgeons use gravity sedimentation (letting the layers separate naturally over time), washing with saline, or filtering through sterile gauze or metal sieves. The goal with any method is the same: isolate the highest concentration of living fat cells to maximize how much survives long-term.
What Happens After Injection
The purified fat is injected into the buttocks in tiny droplets spread across multiple layers of tissue. This technique matters enormously. Small deposits placed near healthy, blood-rich tissue can absorb oxygen and nutrients through diffusion while they establish their own blood supply, a process called neovascularization. Large clumps of fat, by contrast, can’t get nutrients to their center fast enough. The core cells die off, potentially forming cysts or hard lumps, and the volume is lost.
In the days and weeks after surgery, the transferred fat transitions from depending on diffusion to developing its own network of blood vessels. Once that happens, the fat cells are essentially permanent residents. Not all of them make it. It’s normal for 30 to 40 percent of the transferred volume to be reabsorbed by the body in the first few months. What remains after about six months is generally stable for years.
Smoking and nicotine use significantly reduce fat graft survival by restricting blood flow. Without adequate circulation, the new fat cells can’t build the vascular connections they need, and more of the graft dies off.
Recovery Materials That Protect the Results
After the procedure, you’ll wear medical-grade compression garments over the liposuction sites. These aren’t regular shapewear. Stage 1 garments are softer and accommodate foam pads that distribute pressure evenly over freshly suctioned areas during peak swelling. Stage 2 garments provide firmer compression as healing progresses, and Stage 3 garments offer lighter support in the final weeks. The key design detail: these garments compress the donor sites without squeezing the buttocks, since pressure on the newly grafted fat could displace cells or cut off their developing blood supply.
Most patients also use a specially designed pillow or cushion to avoid sitting directly on their buttocks for several weeks. The goal is to protect the fragile fat grafts during the critical window when they’re still establishing blood flow.
Why Safety Matters With This Procedure
Because a BBL is made of your own tissue, there’s no risk of allergic reaction or implant rejection. But the procedure carries a unique and serious risk: fat embolism. If fat is accidentally injected into or near a large blood vessel in the buttocks, fat droplets can travel to the lungs and block blood flow. A 2017 survey published in the Aesthetic Surgery Journal estimated the risk of a fatal or nonfatal fat embolism at 1 in 1,473 procedures, with the risk of death specifically at 1 in 3,448. For comparison, the overall mortality rate for cosmetic surgery in accredited facilities is roughly 1 in 55,000.
Those numbers made the BBL the highest-risk elective cosmetic procedure at the time. Since then, major plastic surgery organizations have issued updated safety guidelines emphasizing that fat should be injected only into the layer just beneath the skin, not deep into or below the gluteal muscle where large vessels are located. Surgeon training and technique are the most significant safety variables.