In a never-ending quest to retain a youthful glow, stars like Gwyneth Paltrow and Sofia Vergara hold fast to their steady diet of lasers. However, like any cosmetic procedure, stepping in front of a laser without the right information may be too intimidating for some. Thanks to New York-based dermatologist, Dr. Dendy Engelman, she reassures us that laser doesn't have to be all that scary. In fact, it can be an effective, low-lift way to look young and treat many concerns. Here, she breaks down the basics of laser, from when to use Fraxel to look like Jennifer Lopez, to the basics of hair removal and how to treat stretch marks.

What are laser facials and how do they work?
Photo facials is what we call them when we are using light based devices to treat the skin. It's very different than what you would think of a traditional facial, which would be like cleansing and peels and microdermabrasion. This is going deeper into the skin to help target pigment and what we call erythema or redness, so we use a broad range of light. It's not specifically a laser, because lasers use specific nanometers of wavelengths of light and that's what laser stands for, Light Amplification Stimulation Emission of Radiation. So, if it's not a specific wavelength—if it's a broad band IPL, Intense Pulse Light, or BBL, Broadband Light—then it's not really a laser, it's a light-based device that we use for photo facials. And because it's a broad range of light, it can target more than one thing. So not all lasers are created equal, some target brown, some target red, some target water to help with wrinkles. Whether you have underlying rosacea or sunspots or if you have a birthmark, things like that, it will be targeted and you will see benefits from it. There's no break in the skin with photo facials so you don't have any downtime or recovery, and when we don't have downtime that's great, but it also means that we probably need more than one treatment. So some of the bigger lasers that get really good results is like one treatment and you are done. When they are less aggressive, the caveat is we have to trade more treatments for no downtime. So usually for photo facials, I do that on a lot of brides, a lot of people who are getting ready for big events, a reunion or whatever, then we'll do three to five treatments once every 3 to 4 weeks.

What are the benefit of laser facials?
Your skin just looks more glowy, it's very pretty. The brown spots, if you had any, may look a little bit darker right afterwards but that's a good response to the light, and then they'll start to flake off or just microscopically release over the next week to 10 days and so that's why it's more of a process because you're getting gradual reduction of color versus resurfacing where it all flakes off. We don’t laser beauty marks or moles to ensure they can monitored appropriately for change.

Is it for all skin types?
No, the furthest I would go with IPL or BBL with the photo facials is skin type 3, maybe 4.

What about problematic skin?
Anecdotally and in some of the laser medicine literature, they will say that light obviously helps with breakouts and that's why you see those Neutrogena monster masks and things like that. They are LED, Light Emitting Diode, so there are different forms of light that are supposed to target either inflammation or target the the follicle and lower the amount of bacteria that causes acne. So, in that way people with acne do respond well and I have some girls who are allergic to everything under the sun or they're so sensitive they can't use the oral or topical medicines that we traditionally prescribe and so that's our only hope. They come in for laser treatments, and that's the concept behind Skin Laundry or some of these places, that are using different lasers.

Who is an ideal candidate for Fraxel laser?
We used to not even talk about Fraxel until people were like 50 or 60 because it was a difference of laser and it was corrective than preventive. If you double your collagen when you don't have very much left at 60, it doesn't make that much of difference. So this is the way that a lot of celebrities keep young, I mean it's crazy the way J.Lo looks like she does at 48 years old, she's amazing.

Can you over laser?
Yes you can, especially if you are in a questionable skin type. There all also laws of diminishing returns at some point where you're like, what are we treating on this perfect skin today? And if you don't know your laser parameters, if you don't respect the power of the device, you can really do harm and that't why we see people who get burned. Even the laser hair centers, I'll get girls in who've been blistered and burned. There are a lot of physics involved, it's not just like follow the pamphlet and put in the settings, which people want to make it so easy and it's not.

Are there treatments that work against laser facials?
You wouldn't want to do a big glycolic peel and then laser, because you have already disrupted some of the epidermis, and then you're going to expose it to more injury. So you want to time those things out if you just had a chemical peel or microdermabrasion.

Do you trust at home laser gadgets?
I do trust them. I trust them for safety because they had to go through rigorous testing in order to do that. We do know that light does help on some level, and my acne patients who are really inflamed and want to step it up a whole other level and they are willing to purchase that, fine. I don't think you need the $400 ones—light is light at that level, so if you want something extra, I do recommend that. I feel like any company who has a lot of funding like a L'Oréal or Neutrogena are the ones who will put their money where their mouth is. You have to find other ways to get self-care at some point, it is better than nothing in some cases if you don't have access to doctors.

How does laser hair removal work?
Ideally, it seems counterintuitive that dark hair is the easiest to treat, but it is. And light hair does not respond to laser because there is no target, so the laser has to have a target in the dermis to hit. So if this is white and this is white, it doesn't have any target to absorb the heat to destroy the follicle. So that's why, even if someone bleaches their hair, if it looks light on the surface but it has pigment at the base, then the laser will go through the skin and selectively hit that. So for lighter hair, it's still electrolysis only, which is so antiquated, but it's the only thing that will give permanent reduction. There are creams that will slow the growth phase, but if you are going to invest that much, either do electrolysis or do laser so that you put that towards something more permanent versus a lifetime of slowing down hair growth, because it doesn't stop it, it just slows it down.

What time of year is the best to start laser hair removal?
We are in the height of laser season right now, when the sun is not bright, it's not that warm, and you have time for recovery. Because what you don't want to do is put sun on a freshly lasered face or skin, because it will have a risk of hyper pigmentation, the skin is more sensitive. It's like baby skin that's remodeling, so just like how we don't put babies in the sun, we wouldn't put baby skin in the sun.

How does laser treat stretch marks?
There are two different types of stretch marks, one are the red ones which are new that have recently been stretched—we see that in a lot of pregnant women or guys who are starting a body building program and they bulk up too quickly—we will treat with Pulsed Dye Laser. So the laser that targets the red, basically it heats that target and that destroys the vessel, the endothelium, the casing of the blood vessel that's there and then it collapses. That's how we can do varicose veins, people who have those strawberry birth marks, things like that. So same concept, you have to pick, if it's for red, we use the vascular laser, if it's for brown we use the pigment laser. So when they're bright and red, we use the red laser and that one's called Pulsed Dye Laser, PDL. And that does pretty well to calm it down because it's acutely inflamed and the skin will usually respond and not leave those white stretch marks that are old. And that's where the skin has been stretched to the point where the collagen bundles aren't as intact and it looks thinner. Those we have to do a Fraxel laser, where we are restructuring the skin and pouring controlled injury into areas to stimulate more collagen.

Is that stretch mark removal permanent?
I've gotten it to where they are virtually imperceptible, but it's just very hard to go back to perfect skin because there's been injury there. Just like how you can have people that have these amazing looking scars, but it's still a scar if you are are really looking.

What are some fears people have when it comes to trying laser?
Pain, efficacy, cost and Google. Anytime I mention Fraxel and they are all on board, and they come back and want a whole other consultation because they have looked at images, if you don't go to someone who knows what they are doing, it can be too much.