The Brazilian Butt Lift (BBL) is a cosmetic procedure that reshapes the body using a patient’s own fat to enhance the volume and contour of the gluteal area. This fat transfer process creates a rounder, fuller silhouette and often improves the hip-to-waist ratio. The procedure is popular because it uses autologous tissue, providing natural-looking results. However, individuals who consider themselves “skinny” or have a low body mass index (BMI) often question whether they possess the necessary body fat for this augmentation.
Why Donor Fat is Essential
The BBL relies on a two-step process requiring a viable supply of fat. The first step involves liposuction, where fat is harvested from donor sites such as the abdomen, flanks, or thighs. The harvested tissue is then purified to isolate healthy fat cells before the second step: strategic injection into the buttocks.
A sufficient volume of transferable fat is a prerequisite for a successful and noticeable enhancement. Surgeons typically aim to transfer fat ranging from 200 cc to 800 cc per side, depending on the desired outcome. This volume must account for natural loss; on average, at least 25% of the transferred fat does not survive the grafting process and is reabsorbed by the body. The primary challenge for patients with low body fat is finding enough harvestable material to achieve a projected outcome that meets their expectations after cell reabsorption.
Techniques for Low BMI Patients
The approach for individuals with low body fat is often referred to as a “Skinny BBL.” This technique modifies the traditional procedure, focusing on maximizing the yield of fat from scarce reserves. Surgeons employ advanced liposuction methods, such as high-definition liposuction, utilizing smaller cannulas to gently extract fat. This careful harvesting helps preserve the viability of the limited fat cells collected.
To secure enough material, the surgeon may harvest fat from multiple donor sites. These areas often include the upper back, inner thighs, and arms, in addition to the typical abdomen and flanks. The goal in these cases is often more about body contouring than massive volume addition. By strategically slimming the surrounding areas, like the waist and flanks, a more defined and projected gluteal contour is achieved.
The volume of fat transferred in a Skinny BBL typically ranges from 300 cc to 700 cc in total. This smaller volume is precisely placed to refine the shape, smooth out hip dips, and slightly increase projection while maintaining a balanced look. Patients must have realistic expectations, understanding that the outcome will be a subtle, proportional enhancement rather than a dramatic change in size.
Determining Surgical Candidacy
Surgical eligibility for a Brazilian Butt Lift is determined by evaluation, with Body Mass Index (BMI) serving as an initial screening tool. While there is no universal minimum, many plastic surgeons require a BMI above 18 or 19, and often prefer a minimum of 20, to ensure enough fat is available. The BMI range ideal for BBL candidacy is between 18.5 and 30, as this balances fat availability with lower surgical risk.
A physical examination is important, as candidacy relies heavily on the distribution of fat tissue. A surgeon must identify sufficient pockets of harvestable fat, even if a patient’s overall BMI is low. An individual may be thin but still carry small, localized fat deposits that can be utilized for a subtle enhancement.
Overall health and a stable weight are important factors in determining eligibility. Patients must maintain a consistent weight, as significant weight fluctuations can compromise the survival of the transferred fat cells. For very lean patients who slightly miss the fat threshold, specialists may advise a controlled weight gain of 10 to 20 pounds before the procedure to increase the harvestable volume. This weight must then be maintained after the surgery to ensure the long-term survival of the grafted fat.
Other Options for Augmentation
For individuals too lean to provide donor fat, or who do not wish to undergo liposuction, alternative methods for gluteal augmentation are available. Gluteal implants offer a reliable solution for increasing projection and volume, regardless of a patient’s body fat percentage. These implants, typically made of soft, solid silicone, provide a substantial increase in size. Implants are often the only option for a dramatic result in very thin patients with a BMI below 20.
Non-surgical alternatives provide enhancement for those seeking minimal change or who lack the fat for a BBL. Injectable dermal fillers, such as poly-l-lactic acid (Sculptra), stimulate the body’s own collagen production to gradually increase volume over time. While they offer limited volume compared to fat transfer, fillers can improve the appearance of hip dips or provide a mild lift. Another option is the use of injectable donor fat products, such as AlloClae, which provide volume without the need for the patient’s own fat harvesting.