Key Points: If your double chin remains even after losing weight, the underlying cause — subcutaneous fat versus skin laxity — determines which treatment is actually appropriate. At Sunshine Dermatology Clinic, Dr. Byunghyun Kim evaluates the structural cause of a soft or undefined jawline before recommending any device, including InMode.
Why Does a Double Chin Persist Even After Losing Weight?
Losing several kilograms through diet or exercise does not always translate to a slimmer jawline. This is a common frustration — one that Dr. Kim hears frequently in consultations. The reason is that fat loss tends to occur unevenly across the body, and the submental area (under the chin) can be one of the last regions to respond to general weight reduction.
One patient in her late twenties came to the clinic after losing more than 5 kg, only to find that her chin and jaw area looked unchanged. She had spent weeks researching lifting devices such as Ultherapy and Thermage FLX, assuming the issue was skin sagging. However, when Dr. Kim examined her manually — gently pinching the tissue beneath the chin — a soft, thick mass of fat was clearly palpable.
This distinction matters enormously. A patient researching lifting treatments for what is actually a fat-volume problem may invest time and money in a procedure that addresses the wrong layer of tissue. That is why Dr. Kim's first step in every consultation is to identify which anatomical layer is responsible before discussing any treatment option.
What Actually Causes a Blurred Jawline — Sagging or Fat?
The tissue beneath the chin is composed of distinct layers: skin, subcutaneous fat, the platysma muscle (a thin sheet of muscle covering the front of the neck), and deep fat beneath it. Understanding which layer is contributing to the fullness is essential for choosing the right approach.
In most cases of a soft, puffy-looking jawline, the primary cause is excess subcutaneous fat — the fat layer sitting just beneath the skin and above the platysma. This is the layer that can be felt when you pinch the area under the chin. If a thick, compressible mass is present, subcutaneous fat is likely the main contributor.
However, not all jawline concerns stem from this layer. A loosened or descended platysma muscle, enlarged deep fat compartments, enlarged salivary glands, or a recessed mandible (lower jaw positioned further back than ideal) can each produce a similar visual appearance but require entirely different treatment strategies. Applying a fat-reducing device to any of these other causes would not produce meaningful improvement.
Dr. Kim notes that patients sometimes arrive having already decided on a specific device after online research. In those situations, a physical examination is still performed first — because confirming the correct cause before proceeding protects both the outcome and the patient's resources.
Why lifting treatments alone may not resolve all jawline concerns
How Does InMode Address Subcutaneous Chin Fat?
When subcutaneous fat is confirmed as the primary cause, InMode is one of the devices Dr. Kim may recommend. InMode delivers radiofrequency (RF) energy into the dermis and the fat layer beneath it using two distinct handpieces — FORMA and FX — each targeting a different tissue depth.
The FX handpiece applies focused, high-intensity electrical pulses to disrupt and reduce fat cells in a concentrated area such as the submental region. This approach works by delivering targeted thermal energy into the fat layer without physically removing tissue, which means there is no incision or recovery period in the traditional sense. Individual responses vary, and the degree of improvement seen across sessions can differ from person to person.
After FX treatment, the FORMA handpiece is used to deliver controlled heat across the full facial area. This step encourages collagen remodeling in the dermis, helping the skin to adapt and tighten as the underlying fat volume gradually decreases. Without this complementary step, the skin in the treated area might feel less firm after the fat has been reduced.
Skin temperature monitoring is a key safety consideration during InMode treatment. The device displays real-time skin surface temperature, allowing the practitioner to adjust energy intensity area by area throughout the session. This helps keep the treatment within an effective range while reducing the risk of thermal injury to surrounding tissue.
What Does an InMode Treatment Course Look Like in Practice?
The patient described above completed three sessions spaced approximately three to four weeks apart. This spacing allows the tissue to respond and partially stabilize between appointments, so that each subsequent session builds on the previous result. Session frequency and total number of treatments may vary depending on individual anatomy and treatment goals.
After the first session, she was uncertain whether anything had changed — a common experience, since the initial response involves biological processes that take time to become visible. By the second and third sessions, she reported that the pinchable fullness beneath her chin felt noticeably thinner, and the contour between her jaw and neck appeared more defined when viewed from the side.
She also noted that the treatment felt less burdensome than she had expected from the devices she had originally been considering, while still delivering results she found satisfying. This kind of outcome — fewer sessions than anticipated and a lower procedural burden — is not guaranteed, but it reflects the importance of matching the treatment to the actual cause rather than defaulting to a more intensive approach.
For those whose jawline concerns stem from causes other than subcutaneous fat — such as platysma laxity, deep fat, or skeletal structure — Dr. Kim explains that InMode would not be the appropriate recommendation, and alternative approaches would be discussed instead.
When Is InMode Not the Right Choice for Jawline Concerns?
InMode FX is designed to target subcutaneous fat. If the fullness beneath the chin is caused by a different anatomical factor, the device is unlikely to produce the change a patient is hoping for. This is why a physical assessment — rather than a device selection — should always come first.
Possible alternative causes include platysma (broad neck muscle) descent or laxity, which may respond better to lifting-oriented treatments. Enlarged submandibular salivary glands can also create the appearance of a full jawline and are not addressed by RF fat reduction. A recessed chin or mandible changes the perceived jaw-to-neck angle and may be better suited to filler augmentation or other structural approaches.
Dr. Kim's approach at Sunshine Dermatology Clinic is to avoid recommending procedures that are unlikely to address the actual issue, even if a patient arrives specifically requesting a particular device. This philosophy — treating what is present rather than what is assumed — is reflected in how consultations are structured, and is discussed further in the clinic's published content on unnecessary treatments.
Frequently Asked Questions
Why hasn't my double chin changed even after losing weight?
Weight loss reduces fat distributed throughout the body, but the submental area (under the chin) can be resistant to general dieting. If subcutaneous fat in that specific region is responsible, targeted treatment of that layer may be needed separately from overall weight management. Other causes — such as loose neck muscle, deep fat, or jaw structure — can also produce a similar appearance and would require different approaches.
How do I know if InMode is appropriate for my double chin?
A physical examination is typically the starting point. If the fullness beneath the chin feels like a soft, palpable mass when gently pinched, subcutaneous fat is likely the primary factor, which is what InMode FX targets. If the cause lies in other layers — such as the platysma muscle, deep fat, or jaw anatomy — InMode may not produce the expected result, and a different approach would be more appropriate.
How many InMode sessions are typically needed for the jawline area?
Session numbers vary depending on individual anatomy and treatment goals. In the example described at Sunshine Dermatology Clinic, three sessions spaced three to four weeks apart were completed. Early sessions may show subtle results that become more apparent over subsequent treatments, as the body's collagen response and fat reduction take time to develop. Individual results can differ.
Is InMode treatment painful, and is there downtime?
Most patients describe InMode as producing a warming or heating sensation during treatment rather than sharp discomfort. The FORMA handpiece is generally well tolerated, while the FX handpiece may feel more intense in localized areas. Skin temperature is monitored in real time to keep the treatment within a safe and comfortable range. Downtime is typically minimal, though individual responses vary.
What is the difference between InMode FORMA and InMode FX?
Both are handpieces used within the InMode platform. FX delivers concentrated radiofrequency energy to target and reduce fat cells in a focused area, making it suitable for localized fullness such as the submental region. FORMA delivers broader RF heat to the dermis across a wider area to support collagen remodeling and skin tightening. The two are often used together in a single session — FX to address the fat layer and FORMA to support skin quality and firmness around the treated area.