What Is Onda Plus and How Does It Work?
ONDA PLUS · COOLWAVES® · EFEM CLINIC
What Is Onda Plus and How Does It Work?
Onda Plus is a non-surgical body contouring device made by DEKA in Italy. It uses a controlled form of 2.45 GHz microwave energy, called Coolwaves®, to heat the fat layer beneath the skin while the surface is actively cooled. Understanding how it works explains both what it can do and where its limits lie: it refines contour in specific areas, but it is not a weight-loss treatment.
KEY POINTS
Onda Plus at a Glance
- Energy: 2.45 GHz microwaves delivered through handpieces with built-in contact cooling.
- Target: the subcutaneous fat layer, plus the fibrous septa involved in cellulite and collagen in the deeper skin.
- Best suited to: pinchable localised fat and cellulite appearance at a stable weight, sometimes with mild laxity.
- Timeline: change builds gradually over weeks; expert recommendations describe a course of four sessions about four weeks apart.
- Not suited to: weight loss, genuine excess skin or a concern driven mainly by loose skin or muscle.
What Is Onda Plus?
Onda Plus is the updated version of DEKA's original Onda system. Both are built on Coolwaves® technology. Onda Plus keeps the two energy-delivering handpieces, Deep and Shallow, and adds a third handpiece called PLUS, which uses rhythmic massage to support microcirculation and drainage.
At Efem Clinic, Onda Plus is one of several body technologies. We choose it when examination shows that the concern comes mainly from pinchable fat and cellulite, not from loose skin, muscle or excess skin. Reading the tissue before choosing the device is the core of The Efem Method™.
How Do Coolwaves® Work? Step by Step
1. Directed delivery
The handpiece emits microwaves in a controlled direction rather than in all directions, while its contact cooling keeps the skin surface cool.
2. Heat builds in the fat layer
At this frequency the skin lets most of the energy pass through. It is absorbed in the subcutaneous fat, where it turns into heat.
3. Fat cells are stressed
Sustained, controlled heating damages fat-cell membranes and causes them to release their contents.
4. The body clears them
Immune cells called macrophages gradually remove the damaged cells. This is why change takes weeks rather than days.
5. Septa and collagen respond
Heat also loosens the fibrous bands that pull the skin down in cellulite and contracts dermal collagen, supporting smoother texture and some firming.
What does the evidence actually show?
The evidence base is still modest. A histology study using a single animal model found fat-cell breakdown and macrophage clean-up peaking around one month after one session, with the skin surface itself unchanged. A small study of 20 women with cellulite on the buttocks and thighs reported improved cellulite scores eight weeks after a four-session course, with no side effects recorded. An international expert panel has since published practical recommendations for using the device. These are encouraging signals, not proof that every patient will respond the same way.
The Three Handpieces
| Handpiece | What it does | Typically used for |
|---|---|---|
| Deep | Delivers microwave energy at greater depth | Thicker fat layers, such as the abdomen and flanks |
| Shallow | Delivers microwave energy more superficially | Cellulite appearance, thinner fat layers and skin texture |
| PLUS | Rhythmic massage, no microwave emission | Supporting circulation and drainage during the course |
Which handpieces are used depends on the area and the tissue. We go through this area by area in our guide to which body areas can be treated with Onda Plus.
How Is It Different From Ultrasound, RF or Laser?
Most body devices use heat, but they deliver it in different ways to different layers. That is what makes one technology a better fit than another for a particular concern.
| Treatment | Energy | Main target |
|---|---|---|
| Onda Plus | Microwaves (Coolwaves®) | Localised fat and cellulite appearance |
| Ultherapy Body | Micro-focused ultrasound | Deeper tightening where skin laxity is the main issue |
| Forma Body RF | Radiofrequency | Skin tightening and tissue quality |
| Morpheus8 | RF microneedling | Skin quality, texture and stretch marks |
| Endolift | Laser fibre placed under the skin | Selected areas of laxity and small fat deposits |
When looseness rather than fat is the dominant problem, Ultherapy Body is often the more logical starting point. Our body treatment technology guide sets all the options side by side, and our article on how Forma Body RF works explains the radiofrequency approach in detail.
What a Course Looks Like
- Before: the area is examined and measured, and the doctor confirms that the concern is mainly fat or cellulite.
- During: the handpiece moves continuously over a contact medium. Most people feel deep warmth; the cooled tip keeps the surface comfortable, and settings start low and are adjusted to tolerance. Expert recommendations describe roughly 30–60 minutes for an area of about 500 cm².
- After: temporary redness, warmth, tenderness or mild swelling can occur. Most people go back to normal activities the same day.
- Over the course: sessions are usually spaced about four weeks apart, and change is assessed weeks after the final session, not the next morning.
Stable weight matters. If your weight is still changing, focusing first on sustainable weight management usually gives a clearer picture of what any body treatment can add.
Who Should Not Have Onda Plus?
The expert recommendations list several situations in which Onda Plus should not be used, including:
- Pregnancy, and breastfeeding in the months after delivery
- A pacemaker, heart implant, or deep brain or sacral nerve stimulator
- Heart failure, kidney or liver failure, or severe vascular disease
- Current or recent cancer, poorly controlled diabetes, or an organ transplant
- Active infectious disease
- Unrealistic expectations
Blood thinners, recent steroid use and varicose veins call for extra caution, and results are generally better closer to a healthy weight. Just as important is the tissue question: if the concern is really loose skin, muscle separation or excess skin, Onda Plus is the wrong tool. Our guide to telling loose skin, fat and muscle apart explains how we make that distinction.
Frequently Asked Questions
What is Onda Plus?
Onda Plus is a non-surgical body contouring device by DEKA that uses controlled 2.45 GHz microwave energy, known as Coolwaves®, to target localised fat and the appearance of cellulite, with some effect on mild skin laxity.
Is microwave energy safe for the body?
The microwaves used are non-ionising energy, which is different from X-ray radiation. The handpiece directs the energy and cools the skin surface. Safety depends on correct patient selection, which is why certain conditions such as pregnancy or a pacemaker rule the treatment out.
Does Onda Plus hurt?
Most people describe deep warmth rather than pain. Settings are started low and adjusted to tolerance, and the cooled handpiece keeps the surface comfortable.
Where do the treated fat cells go?
Damaged fat cells are gradually cleared by the body's own immune cells over the following weeks. This is why results build progressively rather than appearing straight away.
What is the difference between Onda and Onda Plus?
Both use Coolwaves® technology with Deep and Shallow handpieces. Onda Plus adds a third handpiece, PLUS, which uses rhythmic massage to support circulation and drainage.
Does Onda Plus help with cellulite?
It can improve the appearance of cellulite because heat acts on the fibrous bands involved. Cellulite has several causes, so improvement is gradual and complete clearance should not be expected.
Will Onda Plus help me lose weight?
No. Onda Plus is not a weight-loss treatment. It is used for stubborn localised fat and contour when weight is stable, and a change on the scale is not the expected outcome.
How many sessions are usually needed?
Expert recommendations describe a course of four sessions about four weeks apart, but the plan depends on the area, fat thickness, cellulite appearance and how your tissue responds.
Sources and Further Reading
- Hoffmann K, et al. Microwave-Energy-Based Device for the Treatment of Cellulite and Localized Adiposity: Recommendations of the "Onda Coolwaves" International Advisory Board. Bioengineering. 2024;11(12):1249. Expert review and recommendations. doi:10.3390/bioengineering11121249
- Zerbinati N, et al. New System Delivering Microwaves Energy for Inducing Subcutaneous Fat Reduction: In-Vivo Histological and Ultrastructural Evidence. Open Access Macedonian Journal of Medical Sciences. 2019;7(18):2991–2997. Single-animal histology study. PubMed Central (PMC6910790)
- Di Pietro A, et al. Effectiveness of microwaves in the treatment of cellulite: a preliminary study. Journal of Plastic and Pathology Dermatology. 2019;15(3):171–179. Small study of 20 women. PDF hosted by the device distributor
This article is for general information. Suitability, treatment planning and the degree of change you can expect vary with anatomy, tissue, health status and individual response, and online information does not replace a personal medical assessment.
Is Onda Plus the Right Technology for Your Concern?
You don't need to choose a device before your assessment. Send us photos of the area that bothers you, and we can look together at whether it is mainly fat, loose skin, muscle or a mix, and whether Onda Plus fits that goal.
About Dr. Abdurrahman Efem
Dr. Abdurrahman Efem
Dr. Abdurrahman Efem is a medical aesthetic physician specializing in facial rejuvenation, non-surgical aesthetic treatments, and regenerative medicine. His approach focuses on enhancing natural beauty through personalized treatment plans designed around each patient's unique features and goals. Dr. Efem works with both local and international patients, emphasizing balanced, natural-looking results and long-term aesthetic wellbeing. This content has been prepared or medically reviewed by Dr. Abdurrahman Efem to ensure accuracy and relevance.
