Woman touching her cheek and studying her skin in a bathroom mirror

Red light therapy before and after: what to expect, week by week

What does red light therapy before and after really look like?

Gradual. In controlled trials, the changes were measured over weeks: a home LED mask improved crow's feet scores against a sham mask at 8, 12 and 16 weeks, and another trial measured better skin roughness and collagen density after 30 sessions. Before-and-after photos online are uncontrolled, so treat them as stories, not evidence.

Part of the Glow Protocol guide. Start here: The Glow Protocol

Five things worth knowing

Think in months. The trials ran from four weeks of sessions to 12 weeks of home use.
Photos online are not controlled. Lighting, angle and other products all change a picture.
Trials used blinded raters and sham devices. That is what separates a real change from a hopeful one.
Frequency comes from the maker. Brands suggest 3 to 5 sessions a week; two of the trials used two.
Your own photos are your best evidence. Take them the same way every time.

Why online before-and-after photos can mislead

A before-and-after photo shows two moments. It does not show what else changed between them.

Lighting and angle. Soft front light hides lines. Overhead light deepens them.
Makeup and filters. Either can change a photo more than any device.
Other products. A new moisturizer, sunscreen habit or prescription may have started in the same weeks.
Selection. People share their best results. You rarely see the photos where nothing changed.

Trials handle this with a comparison group and blinding. In Park 2025, half the participants used a sham mask, and independent raters scored the results. In Wunsch 2014, the photographs were evaluated blind against a control group. In Lee 2007, only one side of each face was treated, and one group received a sham light.

Illustration of three blocks of skin under red light, each cut open to show a collagen network denser than the one before — *Trials measured collagen changes over weeks of sessions, not days. Illustration, not measured data.*

What the trials found, week by week

When	What was measured	Trial
Weeks 1 to 4	A course of LED sessions twice a week for four weeks, with a three-month follow-up. Wrinkles fell by up to 36% and elasticity rose by up to 19% against baseline. The abstract does not break the result down week by week.	Lee 2007, 76 people with facial wrinkles
Week 8	Crow's feet scores significantly better with a home LED mask than with a sham mask.	Park 2025, 60 adults aged 30 to 65
Week 12	Still significant. This was the last week of use. Independent raters recorded an improvement rate of 86.2% in the mask group, a 69.5% difference from the sham group.	Park 2025
Week 16	Still significant at a follow-up visit, four weeks after use of the mask stopped.	Park 2025
After 30 sessions	Twice-weekly sessions. Better complexion, skin feeling, roughness and ultrasound-measured collagen density than controls.	Wunsch 2014, 136 volunteers (113 treated, 23 controls)

A few honest notes on reading this table.

The earliest sham-controlled difference reported here is at week 8. That comes from the one trial that tested a home mask, which used 630 nm red and 850 nm near-infrared light.

Thirty sessions at two a week is about 15 weeks. That is our arithmetic. The Wunsch abstract reports sessions, not weeks, and it tested large-area light sources, not masks.

The Lee figures are maximums against baseline. The trial also took skin samples and found a marked increase in collagen and elastic fibers in all three treatment groups.

Brands may quote shorter timelines. CurrentBody says its mask shows visible results in as little as 4 weeks. That is the brand's statement.

How long does red light therapy take to show results?

Plan on at least 8 weeks. In the sham-controlled trial of a home LED mask, crow's feet scores were significantly better than sham at 8, 12 and 16 weeks. Another trial used twice-weekly sessions for four weeks, and a third assessed results after 30 sessions. No trial here reported a change within days.

How often should you use red light therapy?

Follow your device's instructions. HigherDOSE suggests 10 minutes 4 to 5 times a week, or 20 minutes 3 to 4 times a week, for its mask. CurrentBody suggests 10 minutes, 3 to 5 times a week. In two of the trials, sessions were twice a week. More time per session is not something these trials tested.

Pick days you can keep. A schedule you follow for 12 weeks tells you more than a burst of daily sessions you drop after two.

How to track your own before and after

Take a baseline photo before your first session. Bare, clean face.
Fix the setup. Same room, same light, same distance, same time of day, same expression. Daylight from a window in front of you works well.
Shoot three angles. Front, left and right.
Repeat every four weeks. Weeks 0, 4, 8, 12 and 16 match the trial timelines above.
Log your sessions. A note on your phone is enough.
Change one thing at a time. If you start a new serum in week 3, you will not know which one did what.
Compare week 0 with week 8 or later. Day-to-day comparisons are noise.

Prep your skin, and where hydration fits

Start each session with clean skin, and follow your device's instructions on anything else. Afterward, use your usual moisturizer, and sunscreen in the daytime.

Where hydration fits. Hydrated skin performs better. By that we mean the skin's own condition: its water content, its barrier and its elasticity.

That is separate from the light. Hydration does not make red or near-infrared light go deeper. In lab optics research on mouse skin, an agent that drew water out of the skin reduced light scattering.

What the evidence says about skin's own water:

In a placebo-controlled trial of 40 adults, 120 mg of oral hyaluronic acid a day for 12 weeks improved outer-layer water content, water loss and elasticity. Wrinkle assessment improved too.
A systematic review of six studies found a slight rise in outer-layer hydration with extra water, mainly in people who drank little. It rated the evidence weak.

One practical point for tracking: if you start red light and a hydration habit in the same week, your photos cannot tell you which did what.

Is red light therapy safe to use for months?

The trials reported LED light as well tolerated. Lee 2007 reported no adverse effects. Park 2025, which ran 12 weeks of use with a follow-up at week 16, described its home mask as safe, well tolerated and painless. A 2013 review noted an almost complete absence of side effects.

Follow the maker's instructions on eye protection and session length. Check with your doctor first if you are pregnant, take medication, or have a skin or eye condition.

What red light therapy does not do

It does not change skin in days.
It does not match the photos you see online. Those are uncontrolled, and often the best case.
It has not been tested here for everything it is sold for. The trials in this article measured wrinkles, elasticity, roughness and collagen. None studied cellulite, gums or eczema.
It does not treat skin conditions. See a dermatologist for acne, eczema or a rash.
It is not made stronger by hydration.

Make it a Glow Protocol

Before. Start with clean, dry skin, unless your device's instructions say otherwise.
During. Follow the maker's session length and weekly schedule.
After. Go back to your usual routine: moisturizer, and sunscreen in the daytime.
Daily. Hydration is the layer underneath, every day. That is Step 0. It supports the skin's own water content. It does not make the light work better.

H2Glow is Step 0: the hydration layer underneath the routine. It does not make any device work better. See the full Glow Protocol.

Where H2Glow fits

H2Glow is Step 0: what is inside your skin before anything goes on it. One stick has 17 actives, including 250 mg of sodium hyaluronate, 40 mg of rice phytoceramides, electrolytes and 1,500 mg of glycine, proline and lysine, collagen's amino acids.

Its job is the skin's own water and barrier, not the light. No study has tested H2Glow, alone or alongside red light therapy.

Frequently asked questions

How long does red light therapy take to work?

In the sham-controlled trial of a home LED mask, crow's feet scores were significantly better at 8, 12 and 16 weeks. Plan on at least 8 weeks of regular sessions.

How often should you do red light therapy?

Follow the maker. HigherDOSE suggests 10 minutes 4 to 5 times a week or 20 minutes 3 to 4 times a week. CurrentBody suggests 10 minutes, 3 to 5 times a week. Two of the trials used sessions twice a week.

Are red light therapy before-and-after photos real?

Some are, but they are uncontrolled. Lighting, angle, other products and choosing the best result all shape a photo. Controlled trials use sham devices and blinded raters to rule those out.

What results did the trials actually measure?

Fewer wrinkles, better elasticity, smoother skin and higher collagen density. One trial measured wrinkle reductions of up to 36% against baseline. Another found crow's feet improved in 86.2% of mask users.

Can you see results from a red light mask in 4 weeks?

CurrentBody says visible results in as little as 4 weeks, which is the brand's statement. One trial ran sessions for four weeks, but the earliest sham-controlled difference reported here was at 8 weeks.

Does red light therapy work on the neck, cellulite, gums or eczema?

The trials in this article did not study those. For eczema or any skin condition, see a dermatologist.

Do results last after you stop?

Lee 2007 followed people for three months after a four-week course, but its abstract does not say how results held at that point. We do not have a clear answer from the evidence here.

Does being hydrated improve red light results?

Not through the light. Hydration does not make light go deeper. It supports your skin's own water content, barrier and elasticity, which is a separate benefit.