It’s no secret that obesity rates worldwide have skyrocketed. While body positivity and “health at every size” movements are gaining popularity and scientific credibility, healthy weight loss can still support your health overall. Additionally, it’s okay to want to lose weight.
Truthfully, there is no magical solution to weight loss – quick fixes often do more harm than good. Losing weight requires eating fewer calories than you burn, hitting your protein goals, following a good exercise program, increasing your NEAT (your everyday movement outside of exercise), and sleeping well.
Having said that, sometimes diet and exercise alone aren’t enough, especially when your efforts plateau. This is why things like red light therapy (RLT), a non-invasive body-sculpting trend, are gaining traction.
I’ve already written a comprehensive article about the pros and cons of red light therapy.
Today, I’ll explore the science behind red light therapy for weight loss. While many weight loss “hacks” are exaggerated, there are credible studies supporting RLT – and it requires no downtime.
So, is it a game-changer, or does it belong in the trash along with the junk fat-burning remedies you’ve tried?
Red light therapy, or photobiomodulation (PMB), bathes specific parts of your body in low-energy red light waves from low-level lasers and red light-emitting diodes (LEDs) to stimulate tissue healing.
It’s also known as cold laser therapy because red light doesn’t generate heat.
However, not all light wavelengths are effective. RLT uses clinically proven red light ranging from 620 to 700 nanometers. Invisible near-infrared (NIR) light waves – from 800-880 nm – also fall under the red light therapy umbrella and penetrate deeper into the skin.
While red light therapy may sound like a new-age spa treatment, it’s backed by science.
So, what does RLT do?
Red light targets cytochrome C photoreceptors in the mitochondria (the energy-producing factories of your cells) (1). This triggers the mitochondrial electron transport chain to make more energy molecules called adenosine triphosphate (ATP). ATP production ramps up during a session and may remain elevated for up to 48 hours afterward.
More ATP helps your tissues to repair, rejuvenate, and function more efficiently.
Research supports RLT for improving collagen production, wound healing, exercise performance, chronic pain, blood flow, and inflammation. Now, evidence suggests RLT may shrink fat cells, target problem areas, and improve body composition when used with other healthy weight loss strategies. Plus, at-home RLT devices allow more people to access the treatment than ever before.
When I first heard about red light therapy for weight loss, I was skeptical. But there is research supporting its effectiveness.
In a 2016 study, researchers used red LEDs to target the waist, hip, thigh, and upper abdomen. Although it was a small study, most participants lost at least 4.5 inches after receiving just one treatment per week for six weeks. Another 2018 study on obese women found that combining red light therapy with exercise three times per week improved body mass index, body fat mass, lean mass, visceral fat, and waist circumference.
I’ll admit, I’m still skeptical about the bold claims that RLT “blasts away” fat. That said, red light laser therapy may actually shrink fat cells. But there must be a catch, right?
Let’s look at the weight loss benefits of RLT and how it works.
If you’ve been extreme dieting and doing hours of cardio, your metabolic rate may be under strain.
Red light therapy ramps up ATP production, which may increase your metabolic rate. In simple terms, it helps your cells burn energy more efficiently.
It’s more of a theory because we don’t fully understand how red light therapy works for fat loss. However, it makes sense considering what we know about how RLT stimulates mitochondrial activity. It may give your metabolism an edge without putting in a ton of effort.
RLT may shrink fat cells, leading to “spot reduction” fat loss.
Studies on RLT have shown that red light waves between 635–680 nm release fatty acids from adipocytes or fat cells (2). Basically, RLT makes the fat cells “leaky”, helping your body metabolize and excrete lipids. This may make it a viable non-invasive alternative to liposuction for body contouring and cellulite reduction.
Shrinking fat cells doesn’t mean they disappear – they still hang around waiting to store fat, so don’t sleep on your other lifestyle changes.
Weight loss always results from a calorie deficit – eating fewer calories than you burn. However, cravings for high-calorie foods and an inability to recognize fullness cues often derail your efforts and result in weight gain.
Red light therapy in the morning may reduce hunger by regulating appetite-regulating hormones like leptin and ghrelin. Leptin is the hormone that decreases appetite, while ghrelin stimulates appetite. This study on sleep-restricted individuals found that red light therapy (used with green light) reduced hunger.
Look, the research on this is in the early stages, and we don’t fully understand why RLT affects appetite. However, I can’t help but think red light therapy influences appetite via the circadian rhythm. The circadian rhythm also controls appetite, digestion, and hormone secretion. However, most of us get way too much artificial blue light exposure (especially at night). This creates a kind of circadian dysregulation that’s f-ing up our appetite and increasing the numbers on the scale. I think red light therapy may help to counteract this modern problem (but it’s a theory for now).
Find out more about how RLT regulates the circadian clock in this article on the red light therapy pros and cons.
Chronic inflammation is a roadblock to losing weight. It’s linked to insulin resistance and metabolic syndrome. If you’re inflamed, your weight probably won’t budge.
Red light therapy may help to lower inflammation by triggering low-level stress in your cells, known as hormesis. This healthy form of stress helps your cells adapt and, in the process, stimulates anti-inflammatory molecules.
Research indicates that RLT may decrease inflammation in actively inflamed cells. It may even improve glucose tolerance by increasing insulin sensitivity.
Muscle tissue is thermogenic – the more muscle you have, the more calories you can burn just by existing. So, you want to maintain muscle mass while losing fat.
Red light therapy may help you meet this goal by improving your body composition.
We know red and NIR therapy may increase muscle mass when used with a regular training program (3). Plus, a study on obese women found three weekly sessions of phototherapy, and physical exercise, reduced fat mass while increasing total skeletal muscle mass.
When it comes to slimming down specific areas, this double-blind, placebo-controlled study found that red light laser therapy three times per week for two weeks reduced waist, hip, and thigh circumference. Furthermore, research shows that RLT treatments may reduce upper arm fat. At the end of the study, those in the RLT group lost an average of 3.7 cm in arm circumference, compared to just 0.2 cm in the placebo group.
Most studies on RLT for “spot reduction” show some benefit. However, RLT is not a magic bullet for achieving a toned physique. But it may give you an edge when combined with other lifestyle changes.
Exercise is one of the foundations of successful fat-burning. Luckily, this is another area where red light therapy can indirectly support weight loss. It stimulates energy production, giving your mitochondria-rich muscles more fuel to maximize your workout.
This study in athletes found RLT improved exercise endurance. Plus, the athletes reported better sleep quality, which is crucial for muscle growth and recovery. The faster your muscles recover, the easier it is to work out regularly.
Overall, RLT is a fantastic companion to aerobic and resistance training for weight loss – as this placebo-controlled study found.
While red light therapy may not be a magic bullet for weight loss, it may increase calorie burning, target fat cells, regulate hunger, reduce inflammation, and improve body composition when used with other healthy lifestyle choices.
Most studies on RLT for fat loss have focused on low-level laser therapy (LLLT) in a clinical setting. In general, these studies use 20-30 minute sessions done 1-3 times per week. For example, this study used a multi-head red laser device on the skin for 20 minutes every other day over two weeks. The results showed a significant 1.12-inch, 0.7-inch, and 1.17-inch reduction in the circumference of the waist, hips, and thighs respectively.
If you choose to use RLT at a medispa or weight loss clinic, you can access high-intensity red light lasers. During sessions, you shed your clothes, slip on a robe, and lie down as a clinician painstakingly passes a handheld cold laser device over the thighs, arms, belly, hips, and buttocks.
Having said that, LED devices for home use are sought-after by those who don’t dig the idea of lying naked while a stranger looks at their jiggly bits. While red LEDs may not work as well as professional laser equipment, research does support their use. So, it’s a viable and convenient option.
You want a medical-grade device that combines red and near-infrared light waves to penetrate adipose tissue. More specifically, look for red light in the 635 nm range and near-infrared light therapy waves in the 800-880 nm range.
A smaller handheld LED device may provide a higher light intensity and better access to stubborn fat areas. However, smaller devices also require more sessions to cover the targeted areas. On the other hand, large LED panels can cover a larger surface area but should be six inches away from your skin during a session. Unfortunately, this means some light reflects off the skin instead of being absorbed.
The good news is red light body wraps and belts could be a better option for targeting the legs, belly, and arms. They give better coverage, are lightweight, and can be directly applied to the skin to increase light penetration. Plus, you can do other things as they’re hands-free. I recommend reading, meditation, breathwork, listening to podcasts, catching up on email admin, or checking in with your family while you do RLT.
Losing weight in a healthy way (focusing on fat loss while maintaining muscle mass) has great health benefits – from more energy and better mobility to a healthier cardiovascular system and reduced risk of diabetes. In addition, RLT offers other benefits like improved sleep, reduced aches and pains, and healthier skin.
We have a whole article to answer this one. Check out the list of the best red light therapy devices out there.
Red light therapy is a non-invasive, drug-free therapy that’s pretty darn safe. Most people experience absolutely no side effects. To be frank, the biggest downside of RLT for weight loss is probably the cost and the time commitment. However, rare side effects may include dryness, redness, and irritation if the device is too close to the treatment area. And one study found that LLLT caused ulceration in two participants.
To minimize risks, use a reputable RLT device, follow the recommended treatment time, avoid eating a large meal before treatment, and stay hydrated before and after your session. If you have light sensitivity, use protective goggles during a session.
If you have an underlying health condition or are taking chronic medication, talk to your healthcare professional before starting any new treatment.
The belly is the most common fat storage area for most of us (especially women). This happens for various reasons, but the common offenders are insulin resistance, metabolic syndrome, and chronically high cortisol levels (aka stress).
Studies indicate that RLT is effective for slimming down stubborn belly fat. It targets adipocytes, shrinking them and giving the abdomen a slimmer and smoother appearance. The Food and Drug Administration (FDA) has approved low-level laser therapy, a form of RLT, as a non-invasive treatment for reducing waist circumference in overweight individuals (4).
This study found using low-level laser therapy between 635–680 nm for 30 minutes twice a week reduced waist circumference by an average of 2.15 cm. The results over one month were cumulative and noticeable in comparison pictures.
Although, for transparency, this study in non-obese people treated only one side of the abdomen with 650 nm red light waves. This split-abdomen study didn’t show a significant reduction in abdominal fat. That said, they only had six treatments overall.
It’s difficult to predict how much bodyweight you will lose using RLT. It depends on your starting weight, the device, the number of treatments, the treatment length, and whether you’re using RLT to support other weight loss strategies.
Unfortunately, weight loss clinics and companies selling red light therapy devices exaggerate the claims and create false expectations. That said, there’s reason to believe using RLT over the long term may result in a significant loss of inches.
Cellulite is a buildup of fat just below the skin that creates an unsightly dimpled appearance. Some people call it the “orange peel” look. While cellulite is normal, anti-cellulite treatments are still huge money spinners, especially among women.
The studies on red light therapy for reducing cellulite have been small and produced mixed results. However, evidence suggests it’s effective for fat layer reduction when used with other anti-cellulite treatments.
Overall, I wouldn’t put a ton of stock in RLT as a cellulite cure.
Weight loss often results in excess saggy skin on your belly, arms, butt, and thighs. Plus, you might have noticeable stretch marks that affect your self-confidence.
RLT can firm up the skin and increase elasticity by stimulating collagen and elastin – structural proteins that may help your skin bounce back after weight loss. While we need more research in this area, existing research shows RLT improves skin elasticity and intradermal collagen density.
Look, it won’t banish stretch marks and excess skin completely, but it may minimize how much your skin changes.
The greatest RLT benefits come from regular usage. However, more is not always better when it comes to RLT. Using it too often can have the opposite effect and stress your cells.
If you’re using a device at home, 15-20 minutes 2 to 3 times per week is plenty if you’re targeting the right areas. If it’s your first time using RLT, start with 5 minutes and gradually increase your time.
This depends on the power density, the dose, and the length of each treatment. The power density (measured in milliwatts/cm2) is the distance of the light from your skin during treatment. The closer the device is to your skin, the more photons hit your skin, and the greater the power. The dose is the power density multiplied by the treatment time. A higher dose penetrates deeper into the skin to affect fat loss.
According to studies, changes in measurements and appearance may be noticeable in as little as 4-6 weeks if you’re consistent.
A 2020 study looked at the effects of twelve red light therapy treatments at different intervals – three times weekly for a month, twice weekly for six weeks, or once weekly for three months. Interestingly, the best weight loss results were in those who had RLT treatments twice weekly for six weeks. It reduced waist circumference, body mass index, and body fat mass. Participants also noticed greater body confidence at the end of the study.
Some studies have even shown benefits after just two weeks. That said, you’re more likely to need regular treatments over 10 to 12 weeks for noticeable differences. But, if you use RLT as a standalone therapy, you won’t see a transformation if you still eat crap and stay sedentary.
There’s no doubt red light therapy holds promise as a low-risk weight loss tool. However, the clinical trials on fat reduction have been small and short-term, with few control groups. It’s not a great look.
Overall, when it comes to weight loss, small changes add up – like walking to the store instead of driving, getting to bed an hour earlier, or replacing starchy foods with fiber-rich veggies. It’s the same with red light therapy; it may give you the extra boost you need on your health and wellness journey.
Finally, consult a healthcare professional before starting RLT to determine if it’s for you.