Red Light Therapy for Stomach: Waist, Skin and Stretch Marks
Red light therapy for stomach goals works on the skin and the tissue just beneath it: trials have measured small, short-term drops in waist circumference and some improvement in the look of stretch marks, while body weight stayed about the same. It is best treated as an add-on to exercise, skin care and medical advice, not a way to lose weight. Below: each belly goal, the waist and stretch mark studies, pregnancy and C-section rules, light depth, trial settings and panel set-up.
Key takeaways
- In a placebo-controlled trial of 67 adults, 635 nm laser light on the waist, hips and thighs three times a week for 2 weeks reduced waist circumference by 0.98 inches. Jackson, 2009
- In a sham-controlled trial of 40 adults, light on the waist, waist measurements fell about 0.4 to 0.5 cm per session more than with sham, while weight and BMI did not change. Caruso-Davis, 2011
- In a 2024 trial on old white stretch marks, 808 nm light gave a median 40% patient-rated improvement at 3 months, which the authors found statistically comparable with fractional CO2 laser. Hafez, 2024
- Computer modelling of human skin puts the deepest light penetration at about 5.4 mm, with longer wavelengths reaching further. Ash, 2017
- Cleveland Clinic says red light therapy "appears to be safe" in the short term when used as directed. Cleveland Clinic
What can red light therapy for stomach skin help with?
People put light on the belly for five main reasons: waist measurements, firmer skin, stretch marks, period cramps and digestion. The evidence is strongest for small changes in waist measurements and the look of stretch marks, and the light acts on the skin rather than the organs underneath.
| Goal | What the research shows | Read more |
|---|---|---|
| Waist size | Small drops in circumference over 2 to 6 weeks of clinic sessions; weight barely changed | This article, and our weight loss guide |
| Loose skin | Light can firm skin quality; it does not remove surplus skin | Our loose skin guide |
| Stretch marks | A small trial found old white marks looked better after 8 to 12 sessions of 808 nm light | This article, and our scars guide |
| Period cramps | Small trials of red light on the lower belly reported less pain | Our period cramps guide |
| Digestion | Early work in mice and one case report only | The depth section below |
Every study in this article applied light to the skin from outside the body.
Does red light therapy for belly fat work?
Trials of red light therapy for belly fat measured small reductions in waist circumference, not weight loss. Weight and BMI barely moved in the studies that tracked them.
A bariatric surgeon quoted by Prevention said light is "more for body contouring than weight loss". Prevention, 2025 Three trials did most of the work on the waist, all with red lasers at or around 635 nm.
- Jackson, 2009: a double-blind, placebo-controlled trial of 67 adults with a BMI of 25 to 30. Three sessions a week for 2 weeks on the waist, hips and thighs. Jackson, 2009
- Caruso-Davis, 2011: 40 healthy adults, light or an inactive device on the waist twice a week for 4 weeks. Blinded photo ratings improved by 1.21 points on a 0 to 3 scale. Caruso-Davis, 2011
- Thornfeldt, 2016: 54 adults, once a week for 6 weeks, with no comparison group. Weight went from 79.0 to 78.3 kg, which the authors called not clinically meaningful. Thornfeldt, 2016
In the cell work behind the 2011 trial, fat cells released stored fat "without inducing lipolysis or cell lysis". Caruso-Davis, 2011 That is a working explanation, and researchers are still testing it.
Some waist studies that appear in searches, such as a 2020 Mayo Clinic pilot, used green 532 nm lasers. Croghan, 2020 They are a separate evidence base from red light. For the full trial list, exercise studies and fat freezing, see our guide to red light therapy for weight loss.
How many inches did the waist trials measure, and did the change last?
In the placebo-controlled trial, the waist alone came down 0.98 inches after 2 weeks of sessions. The changes were measured right after short courses, and part of them returned within weeks.
Across the waist, hips and thighs combined, the treated group lost 3.51 inches against 0.684 inches with placebo. Jackson, 2009 Two weeks after the last session, the treated group had regained 0.31 inches in total.
In the 2011 trial, people whose weight stayed within 1.5 kg had 2.15 cm less waist after 8 sessions. Caruso-Davis, 2011 Weight, BMI and blood pressure did not change, and no side effects were reported.
In the open study, the waist was 1.8 inches smaller and the upper abdomen 1.3 inches smaller two weeks after the course. Thornfeldt, 2016
These trials were small and short, and each tested one clinic device. A narrative review concluded light works best as an add-on for people who are already active. PMFA Journal Keeping any change depends on diet and exercise.
Can red light tighten loose belly skin after weight loss or pregnancy?
Light can firm skin quality, but it does not tighten loose skin. It will not take up surplus skin left after a large weight loss or a pregnancy.
Belly skin after major weight loss has more area than the body needs, and studies of it have found depleted collagen. Light works on the quality of the skin that is there, not on its amount. Our guide to red light therapy for loose skin sets out what firming can and cannot do, and expects 8 to 12 weeks of regular sessions.
A dermatologist quoted by Prevention said light can make skin look firmer and less saggy, and that overuse can irritate the skin. Prevention, 2025 After a pregnancy, start only once you have finished breastfeeding and a doctor agrees.
Does red light help stretch marks on the stomach, and do new or old marks respond better?
Light and laser treatments can make stretch marks less noticeable, though no treatment removes them. New red, pink or purple marks respond better than old white ones.
The NHS says laser and light treatments may improve how stretch marks look but "will not get rid of them". NHS The American Academy of Dermatology calls stretch marks permanent "Like any scar" and says in-office treatments can make them less noticeable. AAD
The closest light trial tested old white marks, about 7 years old on average, in 30 people with skin types III and IV. Hafez, 2024
- Light: 808 nm near-infrared, held 50 cm from the skin, median 14.27 minutes.
- Schedule: 8 to 12 sessions, 2 to 3 a week, over 4 to 6 weeks.
- Result: median patient-rated improvement of 40% at 3 months, against 70% with fractional CO2 laser.
- Comparison: the authors found the two statistically comparable, and the light group reported no side effects in months 1 and 2.
Our guide to red light therapy for scars and stretch marks covers creams and other options. If you use a prescription cream or take any medicine, check with your pharmacist or doctor first, because our precautions rule out use with photosensitising medication.
Can you use red light on your belly while pregnant, breastfeeding or trying for a baby?
No. Our precautions rule out use during pregnancy, and the panel manual also lists breastfeeding and preparing for pregnancy among its warnings.
This matters most for the stomach, because the light falls directly over the abdomen. The rule is about the person in front of the panel, so a partner can keep using it.
The AAD also advises checking with your doctor before any stretch mark treatment while pregnant or breastfeeding. AAD Our article on red light therapy while pregnant explains when to start again after the birth.
When can you use red light on a C-section or tummy tuck scar?
Only once the wound has fully closed and your surgeon, doctor or midwife agrees. Never use light over stitches, staples, an open wound or broken skin.
After a C-section, the breastfeeding rule applies too, so wait until you have finished breastfeeding as well. Then the scar routine applies: bare, clean skin and regular sessions over 8 to 12 weeks.
For timing after any operation, see our guide to red light therapy after surgery.
Can red light on the lower belly ease period cramps?
Small trials of 610 to 630 nm light on two points of the lower belly, 20 minutes a day for about 5 days each cycle, reported less period pain. The research is promising and still early.
Our guide to red light therapy for period cramps has the trials, the placement and the settings. Do not use a heat pad and the panel on the same skin at the same time.
How deep does light reach into the belly, and can it help digestion?
Red and near-infrared light work in the skin and just beneath it: modelling puts the deepest penetration at about 5.4 mm. Longer wavelengths reach further, which is why near-infrared goes deeper than red.
In the modelling study, "Penetration depth increases with increasing wavelength." Ash, 2017 A study of 30 people found 830 nm passed through skin better than 660 nm, and skin tone changed how much got through. Girasol, 2021
Early work in mice and a single case report suggest light on the abdomen may shift gut bacteria, and this has not been tested in controlled human trials. Bicknell, 2019
See a doctor, not a light device, for any of these:
- Pain: severe or persistent stomach pain.
- Bleeding: any unexplained bleeding.
- Other signs: vomiting, fever or a sudden change in bowel habits.
- Stretch marks with other changes: the NHS advises seeing a GP if large stretch marks come with more fat on the chest and tummy and slim arms and legs. NHS
What settings did the stomach and waist studies use?
The waist trials used 635 nm clinic lasers for about 20 to 60 minutes a session, 1 to 3 times a week, for 2 to 6 weeks. The stretch mark trial used 808 nm light 2 to 3 times a week for 8 to 12 sessions.
| Study | Light | Minutes per session | Sessions a week | Weeks |
|---|---|---|---|---|
| Jackson 2009, waist, hips, thighs | 635 nm laser | About 20 | 3 | 2 |
| Caruso-Davis 2011, waist | 635 to 680 nm laser | About 30 | 2 | 4 |
| Thornfeldt 2016, waist and upper abdomen | 635 nm diodes | 30 front and 30 back | 1 | 6 |
| Hafez 2024, white stretch marks | 808 nm diode, at 50 cm | Median 14.27 | 2 to 3 | 4 to 6 |
| Period cramp trials, lower belly | 630 nm LED patches | 20 | About 5 days per cycle | 3 cycles |
The 20-minute figure for the 2009 trial comes from the PMFA review. Clinic laser minutes and distances do not transfer directly to a panel. What carries over is the pattern: bare skin, red and near-infrared light, 2 to 3 sessions a week, and a review after several weeks.
How do you use a Kivorla panel on your stomach?
Stand or sit with your belly bare about 12 inches from the panel, goggles on and eyes closed, and run the red and near-infrared channels for 10 to 15 minutes. For the waist, do the front, then turn and do the back, 2 to 3 times a week per area.
The 9-Spectrum Red Light Therapy Panel carries 480, 590, 630, 660, 670, 810, 830, 850 and 1060 nm, each dimmable from 1 to 100%. Its 630 and 660 nm channels sit either side of the 635 nm used in the waist trials, and 810, 830 and 850 nm sit close to the 808 nm of the stretch mark trial. The panel measures 640 x 230 mm, about 25 x 9 inches.
- Position: hang it on a door or wall with the included door hook, pulley, hanging cables and screws, so its centre is level with your belly, or stand it upright on the floor.
- Distance: about 12 inches, the panel's distance for a broad area. The 6 inch distance is for a single small spot.
- Channels: 630, 660 and 670 nm on; 810, 830 and 850 nm on; 480 and 590 nm at their lowest. Continuous light is fine; avoid flashing at 3 to 30 Hz.
- Timer: 10 to 15 minutes per area, set with the controller. If no time is set, the panel stops at 5 minutes.
- Skin: bare and clean, with creams and lotions removed. The surface stays at or below 40°C; warm is fine, hot means stop.
- Eyes: goggles on and eyes closed for the whole session; never look into the panel.
- Tracking: measure with a tape at navel level, weekly, at the same time of day, before the session, and take photos in the same light.
To start gently, use a shorter timer (it starts at 1 minute) or turn each channel down from 100%. Leave at least 6 hours between 30-minute sessions, and keep up regular exercise: light works alongside training, not instead of it.
The 4-Wavelength Red Light Therapy Mask is a full-face shell for the face only, so it is not used on the stomach.
Do not use the panel if you are pregnant, breastfeeding or preparing for pregnancy, have epilepsy or seizures triggered by light, have a thyroid condition or take thyroid medication, take photosensitising medication, have had sunburn on your body in the past 2 weeks, have broken skin on the area, or have Fitzpatrick skin type V or VI. It is not for use while asleep. Goggles and a controller are included.
Standard shipping to the US, UK and Germany is free. Read the precautions before ordering. Under our return and refund policy, returns are accepted within 30 days: an unopened device with its seals intact is refunded less a 10% restocking fee, and an opened device that is undamaged and complete is refunded less 20%.
Kivorla devices are general wellness devices, not medical devices, and are not a treatment for obesity, stretch marks or digestive problems. See a doctor for persistent stomach pain, bleeding or a change in bowel habits, and before using light after pregnancy or surgery.