This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
10 Apr 2023
PONE-D-23-07622Evaluating the Effectiveness of Laser Hair reduction using a Home use Laser in comparison to a Diode LaserPLOS ONE
Dear Dr. Mpofana,
Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.
Please submit your revised manuscript by May 25 2023 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at gro.solp@enosolp. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.
Please include the following items when submitting your revised manuscript:
A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.
If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.
If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.
We look forward to receiving your revised manuscript.
Kind regards,
Michael R Hamblin
Academic Editor
PLOS ONE
Journal Requirements:
When submitting your revision, we need you to address these additional requirements.
1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at
https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and
https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf
Additional Editor Comments:
You must be clear about the difference between laser and IPL. The mechanisms of action need to be further explained. The limitations must be further discussed. Additional references are required as mentioned
[Note: HTML markup is below. Please do not edit.]
Reviewers' comments:
Reviewer's Responses to Questions
Comments to the Author
1. Is the manuscript technically sound, and do the data support the conclusions?
The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.
Reviewer #1: Yes
**********
2. Has the statistical analysis been performed appropriately and rigorously?
Reviewer #1: I Don't Know
**********
3. Have the authors made all data underlying the findings in their manuscript fully available?
The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.
Reviewer #1: Yes
**********
4. Is the manuscript presented in an intelligible fashion and written in standard English?
PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.
Reviewer #1: Yes
**********
5. Review Comments to the Author
Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)
Reviewer #1: The title is inaccurate and misleading. It should read: "Evaluating the effectiveness of laser hair reduction using a home-use intense pulsed light device in comparison with a professional diode laser"
There must be a distinction between 'laser' and 'intense pulsed light' as they are radically different technologies and this must be maintained throughout the article to avoid misunderstanding.
The mode of action in the introduction needs to be clarified and expanded.
Retinal injury is not the only risk, consider the pigmented iris!
In the discussion, there is insufficient reference to published data on safety of home-use IPL devices (see attachment).
Te statements about loss of skin contact and light spillage require clarification and expansion (see attachment).
The text about US FDA 510k pre-marketing clearance of the devices used in this study relates only to permission to sell a product in the USA based on predicate information and has no relevance to this study. Reference FDA clearances is correctly used in the conclusions.
The Conclusions need to be revised and expanded to include limitations of this study e.g. small sample size, need for more randomised, controlled studies, etc .(see attachment).
Several important references are missing including recent publications in international peer-reviewed journals including:
Trelles M, Ash C, Town G. Clinical and Microscopic Evaluation of Long-Term Epilation Effects of the iPulse Personal Home-Use Intense Pulsed Light (IPL) Device. J Eur Acad Dermatol Venereol. 2014; 28(2):160-168.
Town G, Botchkareva N, Uzunbajakava N, Nuijs A, van Vlimmeren M, Ash C, Dierickx C. Light-based home-use devices for hair removal: Why do they work and how effective they are? Lasers Surg Med. 2019; 51:481-490. Early View online: https://onlinelibrary.wiley.com/doi/10.1002/lsm.23061.
Hatterskey AM, Kiernan M, Goldberg D, Dierickx C, Sliney DH, Haedersdal M. Nash JF. Assessment of adverse events for a home-use intense pulsed light hair removal device using postmarketing surveillance. Lasers Surg Med 2023; Mar 8. doi: 10.1002/lsm.23650.Online ahead of print.
Town G, Ash C, Dierickx C, Fritz K, Bjerring P, Haedersdal M. Guidelines on the safety of light‐based home‐use hair removal devices from the European Society for Laser Dermatology. J Eur
Acad Dermatol Venereol. 2012;26(7):799–811. https://doi.org/10. 1111/j.1468-3083.2011.04406.x
**********
6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.
If you choose “no”, your identity will remain anonymous but your review may still be made public.
Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.
Reviewer #1: Yes: Godfrey Arthur Town Ph.D.
**********
[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]
While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at gro.solp@serugif. Please note that Supporting Information files do not need this step.
Submitted filename: PLoS ONE Manuscript_Review 1.docx
Click here for additional data file.(75K, docx)
Do devices for at-home laser hair removal work? Understanding the Technology Behind Home Laser Hair Removal. Short Answer – Yes, they do work.
Before diving headlong into the home laser hair removal world, let's take a closer look at how these devices work. As mentioned earlier, they target hair follicles using laser or IPL technology. The concept is simple, yet the science behind it is fascinating.
Laser hair removal emits a focused beam of light that penetrates the skin and targets the melanin (pigment) in the hair follicles. Melanin is responsible for giving hair its colour, and it acts as a natural conductor of the laser's energy. When the melanin absorbs the laser's energy, it transforms into heat. This heat, in turn, damages the hair follicles, inhibiting their ability to produce new hair.
The laser's wavelength is crucial in this process. It must be precisely tuned to target the melanin without harming the surrounding skin. This is why home laser hair removal machines often come with different settings or intensity levels, allowing you to adjust the treatment according to your skin and hair colour.
On the other hand, intense Pulsed Light (IPL) devices use a broad spectrum of wavelengths to target the melanin in the hair follicles. While they work similarly to lasers, IPL technology is less focused and may be less effective for particular skin and hair types. Laser hair removal devices are generally considered more precise and powerful.
Before we delve deeper into the effectiveness of home laser hair removal machines, let's take a moment to understand what precisely these devices are and how they operate.
A laser hair removal machine is a specialised device that removes or reduces unwanted body hair using concentrated light energy. The technology is based on selective photothermolysis, a process that targets specific tissues (in this case, hair follicles) using a particular wavelength of light. This enables the laser to precisely and safely target hair follicles without causing harm to the surrounding skin.
The process begins by emitting a highly concentrated light beam, typically from a diode, Alexandrite, or Nd:YAG laser. The melanin in the hair follicles then absorbs the light energy, which converts the light into heat. The heat generated is sufficient to damage or destroy the hair follicles, inhibiting their ability to produce new hair.
It's essential to note that laser hair removal is a science-based treatment, and the technology has been refined and perfected over the years. Initially, laser hair removal was performed only by medical professionals in specialised clinics.
However, technological advancements and increased demand have led to the development of home laser hair removal devices, allowing individuals to carry out treatments safely and conveniently in their homes.
As the popularity of home laser hair removal grew, different types of devices emerged in the market.
Laser Hair removal machine uses a focused, coherent single wavelength of light. A laser source emits the light.
The most common lasers used in at-home laser hair removal machines are diode, Alexandrite, Intense Pulsed Light (IPL), and Nd:YAG lasers.
Each type of laser has its specific advantages and is suitable for different skin and hair types. Here are some types of home laser hair removal devices:
IPL (Intense Pulsed Light) Devices:
How do they work? IPL devices use broad-spectrum light to target the melanin in the hair follicles. IPL light heats and damages the hair follicle and inhibits future hair growth.
Popular Brands: Bareskin IPL Device
Diode Laser Devices:
How do they work? The Diode laser devices emit a concentrated light beam. The light is absorbed by the melanin in the hair follicles, disrupting their growth.
Popular Brands: Tria Beauty Hair Removal Laser.
Nd:YAG Laser Devices:
How do they work? Nd:YAG lasers penetrate the skin. Nd:YAG light goes deeper into the skin, making them suitable for a broader range of skin tones.
Popular Brands: Silk'n Infinity.
Alexandrite Laser Devices:
How do they work? Alexandrite lasers: The Alexandrite lasers target hair follicles, inhibiting growth through focused energy. They are effective for lighter skin tones and target the melanin in the hair follicles to reduce hair growth.
Popular Brands: Iluminage Touch.s.
Home laser hair removal devices have various features to ensure safety, efficiency, and user-friendliness. Some of the key features you may find in these devices include:
1. Skin Tone Sensor: Many devices are equipped with a skin tone sensor that analyses your skin colour and recommends the appropriate treatment intensity. This helps to prevent potential adverse effects on darker skin tones, which may be more prone to burns or pigmentation changes.
2. Adjustable Intensity Levels: Devices often come with adjustable intensity settings, allowing you to customise the treatment according to your comfort level and skin sensitivity.
3. Treatment Modes: Some devices offer different treatment modes, such as glide or stamp modes. Glide mode allows continuous treatment over larger areas, while stamp mode provides precise treatment for smaller or sensitive areas.
4. Built-in Cooling Systems: To enhance comfort during treatment sessions, specific devices have integrated cooling systems that soothe the skin and reduce discomfort caused by the laser's heat.
5. Safety Mechanisms: Home laser hair removal devices typically incorporate safety mechanisms to ensure proper use, such as a skin contact sensor that only activates the laser when the device is in contact with the skin.
With the variety of home laser hair removal devices available, choosing the right one for your needs can be overwhelming. Here are some tips to help you make an informed decision:
1. Consider Your Skin and Hair Type: As mentioned earlier, the effectiveness of the treatment depends on the contrast between your skin and hair colour. Choose a device suitable for your specific skin tone and hair colour to maximise results.
2. Read Reviews and Research: Before purchasing, read customer reviews and conduct thorough research on different devices. Look for reputable brands with positive feedback and ensure the device is FDA-cleared for safety.
3. Seek Professional Advice: If you have any doubts about the suitability of home laser hair removal for your skin and hair type, consult with a dermatologist or a licensed laser technician. They can provide personalised recommendations and ensure your safety during the treatment process.
4. Device Size and Ergonomics: Consider the size and ergonomics of the device, especially if you plan to use it on larger body areas. A lightweight and comfortable device will make the treatment process more manageable and enjoyable.
As the saying goes, "Rome wasn't built in a day," and the same holds true for hair removal. While home laser hair removal machines can produce excellent results, setting realistic expectations from the start is crucial.
Hair removal is a gradual process that requires patience and persistence. You won't achieve silky-smooth skin after just one session. Most manufacturers recommend a series of treatments over several weeks or months to see noticeable results. Hair grows in different cycles, and the laser can only target hairs during their active growth phase. Therefore, you need multiple sessions to catch all the hairs at the correct growth stage.
Additionally, individual responses to the treatment may vary. Some people may experience significant hair reduction after a few sessions, while others may require more treatments to achieve similar results. Factors such as genetics, hormonal levels, and lifestyle can all influence how your body responds to the treatment.
Now, let's delve into the research and real-world experiences to assess the effectiveness of home laser hair removal machines. Numerous clinical studies have demonstrated the efficacy of laser hair removal for both professional and home-use devices.
A study published in the "Journal of Cosmetic and Laser Therapy" examined the effectiveness of home-use IPL devices on female facial hair. The researchers found that the IPL treatment led to significant hair reduction and improved patient satisfaction.
Another "Dermatologic Surgery" study evaluated the long-term hair reduction effects of home-use IPL devices on various body areas. The results showed a noticeable reduction in hair growth, with 60-70% of participants experiencing at least a 50% reduction in hair counts.
In addition to scientific research, countless users have shared their success stories with home laser hair removal devices. Many report smoother skin with less hair growth over time, leading to increased confidence and convenience in their grooming routines.
However, it's essential to remember that individual results may vary, and some users may experience better outcomes than others. The effectiveness of the treatment can depend on factors such as the device's quality, the user's adherence to the treatment schedule, and their skin and hair characteristics.
Several factors can influence the success of your home laser hair removal journey. Let's take a closer look at some of the critical elements that can impact your results:
1. Skin and Hair Color: As mentioned earlier, the contrast between your skin and hair colour plays a significant role in the effectiveness of the treatment. The ideal candidate is someone with fair skin and dark hair, as the laser can more effectively target the hair follicles. People with darker skin or lighter hair might find the results to be less noticeable or require more sessions.
2. Hair Thickness and Density: Thicker, coarser hairs tend to respond better to laser treatment compared to fine, vellus hairs. Similarly, areas with higher hair density might require more treatments to achieve desired results.
3. Hormonal Factors: Hormonal imbalances can affect hair growth patterns. For example, conditions like polycystic ovary syndrome (PCOS) can lead to excessive hair growth, making hair removal more challenging. Addressing underlying hormonal issues may be necessary for optimal results.
4. Device Quality: Not all home laser hair removal machines are created equal. Higher-quality devices with more advanced technology and better construction are generally more effective and safer. Investing in a reputable and FDA-cleared device can significantly impact your hair removal experience.
5. Consistency and Patience: To see the best results, consistency is key. Regular treatments, spaced according to the device's guidelines, are essential. It's also important to be patient and understand that hair reduction takes time and several sessions.
Safety should always be a top priority when using home laser hair removal machines. While these devices are generally safe for personal use, there are essential safety considerations to keep in mind.
1. Skin Sensitivity and Patch Test: Before your first complete treatment, perform a patch test on a small area of your skin to check for any adverse reactions or sensitivity. Wait at least 24 hours to ensure no adverse effects before proceeding with the entire treatment.
2. Eye Protection: Most home laser hair removal devices come with safety goggles or shields to protect your eyes from intense light. Always wear the provided eye protection during treatments to avoid eye damage.
3. Sun Exposure and Tanning: Avoid excessive sun exposure and tanning before and after laser treatments. Sunburned or tanned skin can be more sensitive and prone to adverse reactions during treatment.
4. Pregnancy and Medical Conditions: If you are pregnant, have specific medical conditions, or are taking certain medications, consult with a healthcare professional before using a home laser hair removal device.
5. Tattoos and Moles: Avoid treating areas with tattoos or moles with the home laser device, as the laser's energy can cause pigment changes or harm the surrounding skin.
While home laser hair removal devices can be highly effective for many individuals, there are instances where professional help is recommended or necessary.
1. Unsuitable Skin and Hair Types: If you have dark skin or light hair or if you are unsure about your skin and hair type, seeking professional advice is wise. Laser technicians and dermatologists have access to more advanced devices that can accommodate a broader range of skin and hair colours.
2. Complex Areas: Some areas of the body are challenging to treat at home, such as the face or genitals. Seeking professional help for these delicate areas can ensure safety and effectiveness.
3. Persistent Hair Growth: If you do not see the desired results with home treatments, a licensed laser technician or dermatologist can assess your situation and recommend alternative solutions.
4. Sensitive Skin or Medical Concerns: Professional guidance can help determine the best course of action and reduce the risk of adverse effects if you have sensitive skin or specific medical conditions.
In conclusion, home laser hair removal machines are effective and can significantly reduce hair over time. However, managing your expectations is essential and understanding that results may vary depending on individual factors.
By choosing the best device for your skin and hair type, being consistent with your treatments, and following safety guidelines, you can achieve smoother, hair-free skin from the comfort of your home. But remember, when in doubt or encountering any concerns, consulting with a professional can provide personalised guidance and ensure the best possible outcome. Here's to embracing the convenience and confidence of effective home laser hair removal!
This article has been medically reviewed by: Dr. Walters (MD)