Melanin, not energy parameters determine laser success

A 2001 medical paper by some researchers whose work has always impressed me confirms that dark hair is probably the most important factor in laser effectiveness. Their studies on lasered skin showed that penetration “appeared to be a function of wavelength and not fluence.”

</font><blockquote><font size=“1” face=“Verdana, Helvetica, sans-serif”>quote:</font><hr /><font size=“2” face=“Verdana, Helvetica, sans-serif”> Studies reported to date have shown a good depilatory response from patients treated with the normal mode ruby laser (NMRL) over 12 weeks, but a low response over a time period greater than this.

The implications of this study are that it is probably the presence of the correct chromophore in large enough amounts which is required for successful permanent depilation to occur. </font><hr /></blockquote><font size=“2” face=“Verdana, Helvetica, sans-serif”>PubMed: Topping, 2001 (Ruby laser skin penetration study)

Maybe true, but that study was based on Ruby lasers. Can that be generalized to the other lasers?

My experienced shows that fluence is important as is hair color of course. When my upper arms were treated with 28 Joules I had very disappointing results with very little hair reduction. At the next treatment session (which was done at no charge) I had much better results when the fluence was increased to 40 Joules.

No doubt hair pigment is imortant to though. I have some white hairs that absolutely will not respond to the laser and the technician told e to expect that.


Ruby laser light is abosrbed more by melanin, so it may be more of a factor with rubies. Unfortunately, the British researchers who are doing all the best work are using rubies for their experiments. I wish they’d branch out!