Diode Laser Hair Removal vs IPL Hair Removal – Which is best?
I've noticed a lot of laser hair removal clinics state things like:- "Laser is much more effective than IPL" without referring to any reputable sources to back up their claims.
This led me to wonder whether there were any truths to these statements or whether the clinics are simply using this as part of their marketing spiel without any scientific evidence to back it up. In this article, you'll learn the truth (as backed up by scientific data) about which hair removal treatment is the most effective:
Diode vs Laser - What are the Differences Between the Two Treatments?
Without being too technical, lasers are a concentrated beam of light at a specific wavelength. The diode laser, for instance, is set to a wavelength of between 800 and 810nm. The other types of laser, alexandrite, ruby and Nd:YAG, each have their own set wavelengths.
IPL, on the other hand, doesn't have a specific wavelength and instead emits non coherent light in the range of 550nm and 1200nm. You can consider this the "shotgun" approach to hair removal - the IPL device will emit a broad spectrum of light over a large variety of wavelengths in a pulse like fashion.
There is no doubt that both technologies have been proven effective for hair removal. However, there is less certainty over which technology is better, and that's what I wanted to investigate.
The Study - 15 Female Patients with Underarm Hair Removal Treatment
In 2010 a study was performed on 15 female subjects with Fitzpatrick skin type of I to III. None of the study participants had skin types of IV, V or VI. The Fitzpatrick table is shown below for illustration:-
Hair Color (darkest)
White or very pale
Blue, grey, green
Always burns, never tans
Pale white with beige tint
Chestnut or dark blond
Always burns, sometimes tans
Beige to light brown (olive)
Sometimes burns, always tans
Light to moderate brown
Rarely Burns, always tans
Medium to Dark Brown
Rarely burns, tans more than average
Dark brown to black
Each of the participants agreed to having Axillary hair (more commonly known as underarm hair) removal performed.
Diode laser treatment was performed in the left Axilla and IPL treatment was performed in the right Axilla. This essentially meant that the underarm was divided into two halves, one half for the laser treatment and the other for IPL for a direct comparison.
3 treatment sessions were performed with intervals ranging between five and eight weeks between each session. Five weeks after the final session, photos were taken and patients were asked to decide which treatment they thought worked the best. On top of this, hair counts were taken.
The study concluded that both methods of hair removal were as effective as each other. Patient reports and hair counts show that both methods of hair removal were effective for hair reduction at five weeks after the final treatment.
However, the study concluded that IPL was more painful and produced more side effects than the diode laser. The final conclusion from the study is quoted below:-
"Based on the studied sample, and according to the described parameters, the DL caused less pain and fewer side effects compared to the IPL. Both methods significantly reduced hairs, and neither method proved more effective than the other"
Source: The use of 810 nm diode laser versus intense pulsed light (filter 695 nm) in axillary epilation: a comparative study (2010)
One big limitation of this study, in my mind, is that no further analysis was done beyond five weeks after the final treatment. It would have been very interesting to see how the results fared after a long period of up to 6 months after that final treatment.
Only Pale Skin Types
The test was only carried out on patients who had a skin type profile of I, II or III on the Fitzpatrick scale.
For darker coloured skin tones of IV and above on the Fitzpatrick scale, neither diode or IPL hair removal treatments are effective or recommended. However, there is another laser, the Nd:YAG laser, that has been proven both safe and effective for dark coloured skin.
Patient Number too Low
15 participants is too small a number to draw any solid conclusion.
Conflicting Study (2008)
A similar study in 2008 with 9 women considered the efficacy of diode laser hair removal against IPL. In this study, the treatment area was the face rather than the underarm and results were gathered 6 weeks after the third treatment as opposed to five weeks.
The results of this study showed the the diode laser was more effective while being responsible for greater discomfort and side effects from the treatment than the IPL device.
Conclusions from the Studies - It's Complicated
It would be really great to be able to point at one of these treatment methods and proclaim its superiority over the other. However, as is often the case, it's more complicated than that.
From the limited studies that have been done to compare the efficacy of diode laser hair removal with IPL it seems that there are a lot of variables at play. Only when these variables are more closely controlled will we be able to build up a more precise picture.
For instance, while it may seem that these two studies mentioned in this article are similar, in many ways they aren't. Perhaps the most important dissimilarity was the fluence setting on both the diode laser and the IPL machine.
The fluence setting, along with the duration of light exposure, is ultimately responsible for the amount of thermal damage that is caused in the follicle. Obviously, thermal damage is a crucial part of the hair removal process.
Another dissimilarity was the equipment used. The studies used different brands of laser and IPL machines - this would almost certainly invalidate a direct comparison between the two studies.
As with most things in science and biology - there are many shades of grey rather than a simple black and white.
Deciding which Device to Use
Firstly, it should be said that in a normal situation it isn't up to you to decide what type of hair removal treatment is best. This should be up to your dermatologist or hair removal practitioner to decide (usually during a free initial consultation).
However, here are some important factors to consider:-
- Dark Skin types: If you have darker than skin type IV then your only option is either the Alexandrite or Nd:YAG laser. IPL machines are not safe for such dark skin tones, neither is the diode or ruby laser
- Home hair removal: If you want to do hair removal from home then you'll have to use an IPL kit. To my knowledge, there aren't any laser devices that can be purchased for use in the home. The only devices deemed safe and cleared for home use by the FDA are IPL machines.
Final Concluding Remarks
As a final concluding remark - if you have lighter skin tone and darker hair then you'll probably be fine with either laser hair removal or IPL.
There have been a lot of scientific studies to prove that both IPL and laser hair removal are effective to the degree of an average reduction of >70% at three months after treatment.
Unfortunately, a lot of the rhetoric online about which of two treatment methods are better is biased due to an inherent conflict of interest. Furthermore, scientific studies that are neutral aren't very comprehensive and thus far from conclusive.
What are your experiences with IPL or laser hair removal? Share your experiences in the comments below - I would be very interested to hear from anyone who has gone through either of these treatments.