The Science Behind Skin Tightening & How At-Home Skincare Devices Can Firm Up Saggy Skin

The Science Behind Skin Tightening & How At-Home Skincare Devices Can Firm Up Saggy Skin

Skin aging refers to the deterioration in the quality of the skin with age caused by the synergistic effects of chronological aging, photo-aging, environmental factors, and hormonal deficiency. The process of skin aging involves a reduction in the number of vessels that supply the skin and fibroblasts that synthesize collagen, resulting in skin laxity and the formation of wrinkles over time. Noninvasive skin tightening measures have been increasing in popularity for those looking to treat skin laxity and de-wrinkle saggy skin, offering little to no serious complications that might be caused by invasive cosmetic procedures. Many skin-tightening devices work by heating the dermis until it reaches a temperature that unravels the intramolecular hydrogen bonds connecting collagen fibers. As a result, collagen fibers start reorganizing and contracting into forms that are tighter than they were before receiving the treatment. Additionally, the heating process increases fibroblast growth and production which stimulates neocollagenesis, a natural component in the process of wound repair.

Emerging technologies in the skin rejuvenation and repair field include photorejuvenation, radiofrequency (RF), and electrical muscle stimulation (EMS), all of which has their own unique mechanism for generating anti-aging effects. Although these advanced techniques were known and used before in the medical field, they were only recently introduced as non-invasive, relatively safe treatments to reduce fine lines, tighten loose skin, aid in the wound healing process, improve skin color and thickness, and treat other signs of photoaging. With the growing interest in using these techniques to generate anti-aging benefits without surgical intervention, and supporting studies in addition to statistics that demonstrate their efficiency and safety in this regard, easy-to-use skincare devices have been commercially available for individuals to purchase and get similar benefits to professional therapies. In this guide, we will walk you through the origins of these skin-tightening techniques, how they work to rejuvenate and repair skin, their safety level, and how at-home devices can be a safer, more consistent solution to reverse signs of aging and maintain results.   

LED Light Therapy: A NASA Technology for Boosting Collagen Production

Light-emitting diode (LED) light therapy was initially developed by the National Aeronautics and Space Administration (NASA) for the purpose of experimenting with plant growth in space, but it was only recently introduced in the aesthetic field as a non-invasive, nonthermal procedure to improve skin feel and appearance. The depth at which LED lights penetrate the skin depends on the type of wavelength. LEDs trigger biological processes in the skin that eventually result in less inflammation and acne, smoother fine lines, and tighter skin, depending on the wavelength of light used. The following are the three different wavelengths of LED light that are now used for skin rejuvenation and repair purposes.   

  • Blue light (wavelengths around 450 to 495 nm) has relatively short waves and only superficially penetrates the skin, regardless of the intensity of the light source. The epidermis of the skin absorbs blue light then porphyrins become stimulated, producing intracellular singlet oxygen and killing bacteria as a result. This wavelength is commonly used to treat acne. 

  • Red light (wavelengths around 620 to 750 nm) has longer waves compared to blue light, but it still superficially penetrates the skin at the cellular level, with around eighty percent of the energy being absorbed in the first two centimeters. It works on stimulating the production of two essential proteins in the skin: collagen and elastin. Red light energy increases cellular turnover and superficial circulation by increasing the number of mitochondria, which boosts the production of ATP as a result.

  • Near Infrared (NIR) light (wavelengths around 810 to 850 nm) has longer waves compared to both blue and red lights, penetrating the skin at a greater depth. NIR can improve Adenosine triphosphate (ATP) production in the human body which can lead to improvement in overall health by speeding up the wound healing process, reducing inflammation, and boosting immune health. Besides health benefits, NIR helps reverse signs of aging by stimulating fibroblast activity and creating new proteins for collagen and elastin as a result.

Patients can receive the treatment at a clinic or opt for an at-home LED light device. Given that LED light therapy does not use ultraviolet (UV) light and hence does not cause skin damage or burns, both at-clinic and at-home treatments are mostly safe for people with no certain health conditions or who are not on certain medications that increase skin sensitivity to light. “For the most part, these LED light therapies appear to be relatively safe, at least in the short term,” says Dr. Elizabeth Buzney, assistant professor of dermatology at Harvard Medical School.

Radio Frequency (RF): Nonsurgical Facelift with Electromagnetic Radiation

Radiofrequency (RF) skin tightening is a noninvasive treatment during which RF electrodes are externally applied to the target area. When the radiofrequency energy is applied to the skin, it gets into the tissue at a depth of a few millimeters. The RF current passes through the epidermis and makes its way to the collagenous tissue in the dermis and subcutaneous fat. The treatment aims to achieve a relatively strong collagen contraction effect by heating deep dermal collagen, which enhances skin tightening and improves deep wrinkles. “Radio Frequency is a type of electromagnetic radiation at a specific frequency range. A wavelength is the distance between two peaks of a wave. The frequency is how many wavelengths form in one second,” explains Dr. Cassandra Bankson, a certified skincare expert and medical aesthetician and founder of San Francisco-based company CBLLC. “We categorize these different frequencies and wavelengths in the electromagnetic spectrum. Radio frequencies are the lowest energy electromagnetic radiation. They have a longer wavelength and likewise a lower frequency because each wavelength takes longer to complete. Radiofrequency involves using energy from these waves to heat the deep layer of your skin known as your dermis. This heat stimulates the production of collagen. Collagen is the most common protein in your body, and stimulating it can improve signs of wrinkles and sagging skin.”

Researchers found that radiofrequency devices can be effective for improving wrinkles volume via the stimulation of fibroblast collagen production. A systematic review published in May 2021 tested the effectiveness of home-based RF devices for skin rejuvenation and repair. After one treatment, the results revealed that the eyebrow-to-hairline distance was reduced by 1.521cm, with no reported adverse events. Another home-based RF device was tested on 45 patients. They were all treated five times a week for four weeks. Following the treatment, they received maintenance therapy two times a week for seven weeks. The skin of treated subjects was significantly improved in terms of elasticity and firmness, with no reported pain by the participants except for mild transient. A 2022 study aimed to compare the anti-aging benefits of home-based RF beauty devices with those of commercially available anti-aging cosmetics. This randomized, controlled, split-face trial tested the effects on 33 women aged 35–60 years throughout a time period of 12 weeks with 5 repeated measurements that are at baseline, 2, 4, 8, and 12 weeks. The experimental group was signified by one randomly-selected side of the face, which was the at-home RF device. The other side of the face was considered the control group, which was treated using the commercially available anti-aging cosmetic. After evaluation, participants in the experimental group saw a significant improvement in wrinkles, skin thickness, color, and radiance.  

Electrical Muscle Stimulation (EMS): Achieving a Sculpted Look By Activating Facial Muscles 

Electrical muscle stimulation (EMS) is based on the application of electrical current forms with the aim of artificially activating muscles. Those electrical current forms have been long applied to the whole body or just locally to induce involuntary muscle contraction in the treated area, producing an effect on the target muscle similar to exercising but without the patients feeling the discomfort. Essentially, EMS strengthens and maintains muscle mass by facilitating the passive activation of motor units and inducing synchronous recruitment of muscle fibers. This technology gives relatively deep stimulation to the facial muscles. 

On the other hand, microcurrent devices and facials are based on the use of low-grade electrical currents to stimulate muscles and skin, purportedly building up face muscles and lifting and tightening the skin. Microcurrent has a variety of applications and functions, such as the stimulation of blood circulation and skin wound healing, improvement of muscle functions, reduction of inflammation, and more. This non-invasive, mostly safe therapy is believed to provide treated patients with anti-aging benefits at a relatively low cost. Research also suggests that microcurrent can speed up wound healing by increasing blood circulation to the treated area and reducing inflammation. In fact, ES therapy has been used to promote wound healing for decades. In 2002, the American Food and Drug Administration approved the clinical use of ES devices in the treatment of certain types of chronic wounds that standard wound therapies had failed to treat. When comparing professional microcurrent devices to at-home devices, the first tends to be more powerful than the latter and gives patients more noticeable results in a shorter amount of time. For more regular and safe use, however, individuals should opt for at-home devices with weaker currents to get similar effects to professional microcurrent treatment. 

As someone seeking to tighten and de-wrinkle sagging skin at home with no surgical intervention or thermal injuries, you do not have to purchase separate devices for getting the anti-aging benefits of the three different skin-tightening technologies: photorejuvenation, radiofrequency (RF), and electrical muscle stimulation (EMS); the EvenSkyn® Lumo is a clinical-grade anti-aging and skin-tightening handset that incorporates these technologies into one, easy-to-use handset, delivering noticeable results within three weeks of use. 


Beilin G. Home-use TriPollar RF device for facial skin tightening: Clinical study results. J Cosmet Laser Ther. 2011 Apr;13(2):69-76. doi: 10.3109/14764172.2011.552607. PMID: 21401380.

Chaudhary M, Khan A, Gupta M. Skin Ageing: Pathophysiology and Current Market Treatment Approaches. Curr Aging Sci. 2020;13(1):22-30. doi: 10.2174/1567205016666190809161115. PMID: 31530270; PMCID: PMC7403684.

Cohen M, Austin E, Masub N, Kurtti A, George C, Jagdeo J. Home-based devices in dermatology: a systematic review of safety and efficacy. Arch Dermatol Res. 2022 Apr;314(3):239-246. doi: 10.1007/s00403-021-02231-0. Epub 2021 May 3. PMID: 33938981; PMCID: PMC8918178.

O’Connor, Kelly, Prasanthi Kandula, Michael Kaminer. 2021. "Non-surgical skin tightening" Plastic and Aesthetic Research. 8: 64.

Shu X, Wan R, Huo W, Li Z, Zou L, Tang Y, Li L, Wang X. Effectiveness of a Radiofrequency Device for Rejuvenation of Aged Skin at Home: A Randomized Split-Face Clinical Trial. Dermatol Ther (Heidelb). 2022 Apr;12(4):871-883. doi: 10.1007/s13555-022-00697-y. Epub 2022 Mar 6. PMID: 35249173; PMCID: PMC9021338.

The University Corporation for Atmospheric Research (UCAR). "Wavelength of Blue and Red Light." Accessed July 11, 2023. 

Whelan HT, Smits RL Jr, Buchman EV, Whelan NT, Turner SG, Margolis DA, Cevenini V, Stinson H, Ignatius R, Martin T, Cwiklinski J, Philippi AF, Graf WR, Hodgson B, Gould L, Kane M, Chen G, Caviness J. Effect of NASA light-emitting diode irradiation on wound healing. J Clin Laser Med Surg. 2001 Dec;19(6):305-14. doi: 10.1089/104454701753342758. PMID: 11776448.

Xu X, Zhang H, Yan Y, Wang J, Guo L. Effects of electrical stimulation on skin surface. Acta Mech Sin. 2021;37(12):1843-1871. doi: 10.1007/s10409-020-01026-2. Epub 2021 Feb 6. PMID: 33584001; PMCID: PMC7866966.

Yoo HJ, Park S, Oh S, Kang M, Seo Y, Kim BG, Lee SH. Effects of electrical muscle stimulation on core muscle activation and physical performance in non-athletic adults: A randomized controlled trial. Medicine (Baltimore). 2023 Jan 27;102(4):e32765. doi: 10.1097/MD.0000000000032765. PMID: 36705372; PMCID: PMC9875983. 

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