Why Autumn Is the Right Season to Start Laser Hair Removal
Laser hair removal is not one treatment but a series, spread over months, and it works best on skin that has not been in the sun. Those two facts together make October one of the best months to begin: the tan has faded, covered skin is the norm for the next few months, and a course started now is well under way, and for many areas close to complete, before the clothes get shorter again.
Laser hair removal is not one treatment but a course of them spread over months, and it works best on skin that has not been in the sun. Put those two facts together and October is one of the best months to begin: your tan has faded, you will be covered up for the next few months, and a course started now is well under way, and for many areas close to finished, before the clothes get shorter again.
Laser hair removal: the essentials
The short version
Light is absorbed by pigment in the hair and follicle and turns to heat that damages the growth structures
Light is taken up by the colour in the hair and its root, turns to heat, and damages the part that grows the hair.
Only follicles in their growth phase are fully susceptible, and hairs enter that phase at different times
Only hairs that are actively growing are fully affected, and different hairs grow at different times.
Long-term hair reduction, not a guarantee that every hair will be permanently gone
A long-lasting reduction in hair, not a promise that every single hair will be gone for good.
No tan to treat around, easy sun avoidance, and a course well advanced by the time summer arrives
No tan to work around, easy to stay out of the sun, and a course well on its way by the time summer arrives.
White, grey and very light blond hair, which contain too little pigment for the laser to target
White, grey and very light blond hair, which have too little colour for the laser to find.
Dr. Gallacher, personally, using the GentleMax Pro with its 755 nm and 1064 nm wavelengths
Dr. Gallacher does it herself, using the GentleMax Pro, which has two different laser settings.
What the laser is actually looking for
What the laser is actually looking for
The principle is selective photothermolysis, described by Anderson and Parrish in 1983: choose a wavelength that a particular target absorbs strongly and its surroundings absorb weakly, and the target can be heated and damaged while the surrounding tissue is spared. For hair removal the target is melanin, the pigment in the hair shaft and follicle. The light is absorbed, becomes heat, and injures the structures the follicle needs to keep producing hair, while a cooling system protects the skin’s surface.
The idea is called selective photothermolysis, and it was described in 1983: pick a laser light that one target takes up strongly and the tissue around it takes up weakly, and you can heat and damage the target while sparing everything else. For hair removal the target is melanin, the colour in the hair and its root. The light is absorbed, turns into heat and injures the part the root needs to keep making hair, while a cooling system protects the surface of your skin.
That explains the rule about colour. The laser needs contrast between the hair, which should be dark, and the skin around it, so dark hair on light skin is the easiest case. As skin deepens in tone, more of the light is taken up by the skin’s own pigment, and the settings and the choice of wavelength have to change to protect it. GentleMax Pro combines a 755 nm alexandrite laser, strongly absorbed by melanin and efficient on fine or light brown hair, with a 1064 nm Nd:YAG laser, absorbed less by melanin and generally the safer choice as skin tone deepens. It is cleared for permanent hair reduction in all skin types, with the wavelength matched to the person.
That explains the rule about colour. The laser needs a contrast between the hair, which should be dark, and the skin around it, so dark hair on light skin is the easiest case. As skin gets deeper in tone, more of the light is taken up by the skin’s own colour, so the laser setting has to change to protect it. GentleMax Pro has a 755 nm alexandrite laser, which is taken up strongly by colour and works well on fine or light brown hair, and a 1064 nm Nd:YAG laser, which is taken up less by colour and is usually the safer choice as skin tone deepens. It is cleared for permanent hair reduction in all skin types, with the laser matched to the person.
The history of how this was discovered, by accident, is in The Accident That Invented Laser Hair Removal.
The story of how this was discovered, by accident, is in The Accident That Invented Laser Hair Removal.
Why one session is never enough
Why one visit is never enough
Hair does not grow all at once. Every follicle cycles through a growth phase, a short regression phase and a resting phase, and at any moment the follicles on one area are scattered across all three. The laser is most effective on follicles in the growth phase, when the hair is attached and rich in pigment. A single session therefore treats only the fraction that happens to be in that phase, and the others are caught on later visits as they enter it.
Hair does not grow all at once. Every hair root goes through a growing phase, a short winding-down phase and a resting phase, and at any moment the roots in one area are spread across all three. The laser works best on roots in the growing phase, when the hair is attached and full of colour. So one visit treats only the share that happens to be growing at that moment, and the others are caught on later visits as they start to grow.
That is the reason for the spacing. Hair on the face cycles faster than hair on the body, so sessions on the face are usually a few weeks apart, commonly four to six, and sessions on the legs, back or chest are further apart, often eight to twelve weeks. Guidance from the American Academy of Dermatology describes roughly two to six treatments for many patients, and some need more, depending on the area, the hair, the skin tone and the device. With each session the treated hairs come back finer, lighter and sparser, and the interval between visits generally lengthens.
That is the reason for the gaps. Hair on the face grows in faster cycles than hair on the body, so visits for the face are usually a few weeks apart, commonly four to six, and visits for the legs, back or chest are further apart, often eight to twelve weeks. Guidance from the American Academy of Dermatology describes about two to six treatments for many people, and some need more, depending on the area, the hair, the skin tone and the laser. With each visit the treated hairs come back finer, lighter and thinner, and the gaps between visits usually grow longer.
It also means the series cannot be hurried. Treating more often than the cycle allows does not reach more follicles, it only irritates the skin.
It also means the course cannot be rushed. Treating more often than the growth cycle allows does not reach any more roots. It only irritates the skin.
Why autumn is the right time to begin
Why autumn is the right time to begin
The first reason is the tan. Laser energy absorbed by tanned skin competes with the hair for the same light, which raises the risk of burns, blistering and pigment change, and recent tanning or sunburn is a standard reason to defer treatment. By October most tans have faded, so treatment starts from the skin’s true baseline. The second reason is sun avoidance. Treated skin should be kept out of strong sun and tanning between sessions, which is easy to do in the cooler months and hard to do in July.
The first reason is the tan. Laser energy that is absorbed by tanned skin competes with the hair for the same light, which raises the risk of burns, blisters and colour change, and a recent tan or sunburn is a normal reason to wait. By October most tans have faded, so treatment starts from your true skin colour. The second reason is staying out of the sun. Treated skin should be kept out of strong sun and tanning between visits, which is easy in the cooler months and hard in July.
The third is the calendar. Visits on the face are a month or so apart and visits on the body two to three months apart, so a course takes many months whatever the area. Beginning in October means that by the time summer arrives, perhaps five or six sessions on the face and three or four on the body have already been done, and the first summer of bare skin comes with much less hair to deal with. Starting in May instead means breaking the course for every holiday and every tan, and not seeing the benefit until the following year.
The third is the calendar. Visits on the face are about a month apart and visits on the body two to three months apart, so a course takes many months whatever the area. Starting in October means that by the time summer arrives, perhaps five or six visits on the face and three or four on the body have already been done, and your first summer of bare skin comes with much less hair to deal with. Starting in May instead means breaking off the course for every holiday and every tan, and not seeing the benefit until the following year.
There is a practical bonus for people whose hair causes recurrent razor bumps or ingrown hairs. Reducing the hair reduces the problem, and doing so during the months when skin is covered and calm is easier than doing it in the middle of summer.
There is a practical bonus for people whose hair causes razor bumps or ingrown hairs. Less hair means less of the problem, and it is easier to get there during the months when your skin is covered up and calm than in the middle of summer.
Preparing, and what to avoid
Getting ready, and what to avoid
Preparation is short and specific. Avoid tanning, including sunbeds and self-tanning products, because they put colour where the laser is looking. Shave the area before treatment, since shaving leaves the hair root in place, and do not wax, pluck or use depilatory creams in the weeks before, because they remove the very hair the laser needs to find. Use sunscreen on the treated area, and tell the physician about medicines, recent isotretinoin use, cold sores and any tendency to scar.
Getting ready is short and specific. Avoid tanning, including sunbeds and self-tan products, because they put colour exactly where the laser is looking. Shave the area before treatment, since shaving leaves the hair root in place, and do not wax, pluck or use hair-removal creams in the weeks before, because they take away the very hair the laser needs to find. Use sunscreen on the treated area, and tell your doctor about any medicines, recent isotretinoin, cold sores and any tendency to scar.
Afterwards, expect temporary redness and some swelling around each follicle, usually settling within a day or two. The treated hairs often seem to keep growing for a week or two and then shed, which is normal and is not new growth. Keep the area out of the sun, avoid heat and friction for a day or so, and shave rather than wax between visits.
Afterwards, expect some redness and small bumps of swelling around each hair, usually settling within a day or two. The treated hairs often seem to keep growing for a week or two and then fall out, which is normal and is not new growth. Keep the area out of the sun, avoid heat and rubbing for a day or so, and shave rather than wax between visits.
What the laser cannot do
What the laser cannot do
It cannot treat hair that has no pigment. White, grey and very light blond hair absorb little of the light, so conventional lasers respond poorly to them, and electrolysis may be the better option for those hairs. It cannot promise that every hair will be permanently gone: the accurate description is permanent reduction, with some regrowth possible, particularly where hormones are driving the hair, and an occasional maintenance session is sometimes sensible.
It cannot treat hair that has no colour. White, grey and very light blond hair take up very little of the light, so lasers respond poorly to them, and electrolysis may be the better choice for those hairs. It cannot promise that every hair will be gone for good: the accurate description is a lasting reduction, with some regrowth possible, especially where hormones are driving the hair, and an occasional top-up visit is sometimes sensible.
Being clear about this at the start is part of the consultation. The aim is a substantial, lasting reduction that makes daily shaving, waxing and plucking unnecessary for most people, and the plan is set for the individual, with the area, the hair and the skin tone all taken into account.
Being clear about this at the start is part of the consultation. The aim is a big, lasting reduction that means most people no longer need daily shaving, waxing or plucking, and the plan is set for you, taking your area, your hair and your skin tone into account.
Questions patients ask
Does laser hair removal hurt?
Does laser hair removal hurt?
Most people describe a brief snapping or stinging sensation, like a rubber band, and the skin is cooled during treatment to protect it and keep it comfortable. Sensitivity varies by area, with the upper lip and bikini line usually more sensitive than the legs.
Most people describe a quick snap or sting, a bit like a rubber band, and your skin is cooled during treatment to protect it and keep you comfortable. It varies by area, with the upper lip and bikini line usually more sensitive than the legs.
Is it really permanent?
Is it really permanent?
The accurate term is permanent hair reduction. Many follicles are disabled for good, but not every one, and some hair can return, particularly where hormones are involved. The result is a lasting reduction, with an occasional maintenance session if it is wanted.
The accurate term is permanent hair reduction. Many hair roots are put out of action for good, but not every one, and some hair can return, especially where hormones are involved. The result is a lasting reduction, with an occasional top-up visit if you want one.
Can I shave between sessions?
Can I shave between visits?
Yes, and it is the preferred way to remove hair between sessions, because shaving leaves the root in place. Waxing, plucking and depilatory creams should be avoided, since they remove the hair the laser needs to target at the next visit.
Yes, and it is the best way to deal with hair between visits, because shaving leaves the root in place. Avoid waxing, plucking and hair-removal creams, since they remove the hair the laser needs to find at the next visit.
Is it safe for darker skin?
Is it safe for darker skin?
It can be, when the wavelength and settings are chosen for the skin. GentleMax Pro is cleared for permanent hair reduction in all skin types, and its 1064 nm wavelength is absorbed less by skin pigment. A consultation matters particularly for darker skin, because the margin for error is smaller and the plan is individual.
It can be, when the laser and settings are chosen for your skin. GentleMax Pro is cleared for permanent hair reduction in all skin types, and its 1064 nm setting is taken up less by the skin’s own colour. A consultation matters especially for darker skin, because there is less room for error and the plan is made for you.
What can I do about white or grey hairs?
What can I do about white or grey hairs?
Conventional lasers respond poorly to white, grey and very light blond hair because there is too little pigment to absorb the light. Electrolysis, which treats each follicle individually, may be the better option for those hairs, and it can be used alongside laser for mixed areas.
Lasers do not work well on white, grey or very light blond hair, because there is too little colour for the light to find. Electrolysis, which treats each hair root one at a time, may be the better choice for those hairs, and it can be used alongside laser where the hair is mixed.
- Anderson RR, Parrish JA. Selective photothermolysis: precise microsurgery by selective absorption of pulsed radiation. Science. 1983;220(4596):524-527. Source
Where to go next
Talk it through with a physician first.
Every plan starts with an assessment of your skin, your anatomy and what you actually want to change.
This page is general health information, not medical advice. It cannot tell you whether a treatment is right for you. Approved uses, risks and results differ from person to person, and product labelling changes. Ask us at Dermatology and Laser Centre about your own situation, or make an appointment, and seek urgent care for any serious symptom.
