Danielle Pavliv, Sandy Wang and Varuna Srinivasan, National Center for Health Research
Wouldn’t it be great if we could each shed a couple of inches off our waist without having to diet or exercise? For years, millions of Americans have tried pills, injections, “natural” herbs, and even berries that are supposed to help us shed pounds. Unfortunately, these usually don’t work.
The latest magical way to lose weight is infrared light, also known as “red light therapy” or “low light therapy”
Infrared therapy is also suggested for pain management, jaundice, eczema, wrinkles, scars, improved blood circulation, and to help wound and burns heal faster. That doesn’t mean it actually works for any of those things. But in this article, we’re focusing on whether it works to help you look thinner. 1
Light therapy uses near infrared light, usually from lasers, lamps, or tanning bed-like devices. The patient is told to either lie down or sit in front of the light for a specific amount of time on a regular basis (usually once a day). One popular device is the infrared body wrap, consisting of large silicone bandages or pads that emit infrared light around the legs, torso and arms. In addition, patients are told that red light therapy is supposed to improve the appearance of cellulite and help shape the body.
If it sounds too good to be true, it probably is. There is little scientific evidence supporting the claims that infrared light, whether administered by lamp, laser or while in a body wrap, can help people lose weight or shape their body. Nevertheless, in 2010, the FDA cleared a laser called Zerona, manufactured by Erchonia Medical Inc., which uses red light therapy to remove “unwanted” fat without surgical procedures. This device is not approved by the FDA – it is “cleared for market”, which is a different cleaning service process that does not require that a device be proven safe or effective. Since 2010, several devices using the same technology have been cleared for marketing in the U.S. for body contouring and fat reduction. 2
Light therapy has been tested in clinical trials of patients, but these studies were not as scientific as they would need to be to prove safety or effectiveness. Most studies have few patients who have very similar demographics. Since the patients and clinicians know that the patient is being treated, and in most studies the patients getting treatment weren’t compared to patients getting a different treatment, this could result in a type of “placebo effect.” The placebo effect is when patients believe in a treatment and for that reason it seems to help even if the treatment isn’t actually effective. Also, the companies that make the light therapy devices provided funding to conduct the studies, which can result in overly optimistic results.
Despite all these substantial shortcomings, the studies showed only a small benefit from the light therapy. So, even if the treatment has some benefit, which is doubtful, the benefit may not be substantial enough to be worth the time and money for the treatment.
In addition, all of the studies were short – none were more than 4 months long, and none followed up with the patients for more than a few weeks after treatment. So, we cannot know how long even small changes might last or what might happen if patients continued the treatment for years.
And what about the risks? Almost all of the studies did not provide any information about potential side effects of the therapy. However, one study done in Poland looked at the effects of LLLT used in close contact with the skin. They found that patients developed skin ulcers as a result of certain types of lasers. 3
What exactly do the studies show?
A study funded by Erchonia (the company that makes Zerona) included 54 overweight or obese patients.4 Most of the patients were Caucasian men which is odd, since most weight loss patients are women. The patients were treated weekly for 6 weeks. The study found a significant reduction in the combined circumference of hips, waist, thighs, and upper abdomen by 13 cm (about 5 inches) after 6 weeks. Two weeks after the final treatment, patients lost another 2 cm (about 0.8 inches). However, patients knew that they were getting this treatment and may have changed their diet or exercise in an effort to succeed. These patients were not compared to a control group, so we can’t tell how much patients would have changed without the treatment. Also, patients were only studied for two weeks after their last treatment, so we do know how long this reduction lasted.
Whether or not infrared therapy is effective on its own, some scientists are studying whether it can potentially boost the benefits of exercise. To do this, they study obese patients all of whom are in an exercise program. Half the patients also get light therapy and the other half don’t. Results in these studies show us that it is possible that infrared therapy boosts the effect of exercise on weight loss. However, the studies were not well designed so it is impossible to know.
A study in Brazil tested whether LLLT and aerobic exercise could reduce the chances of obese women developing heart disease.5 It was a well-designed study: 62 women were given an exercise regimen and randomly assigned to either be exposed to LLLT or a placebo for 4 months. LLLT increased the effectiveness of aerobic exercise to improve the women’s heart health. The scientists reported that LLLT reduced the abdominal fat and the women’s total body fat as measured by waist circumference and other measures. However, the study did not follow the women after their 4 months of treatment, so we don’t know how long the effect lasted.
Another device using Water Filtered Infrared Radiation (known as wIRA) is currently being studied to see if it helps patients lose weight.6 In this study, all 40 patients engaged in aerobic exercise 3 times a week for 4 weeks, with some patients also treated with wIRA while exercising. Although they were able to show a statistical difference in weight loss between the two groups (p<0.001), there were so few people in the study to be certain, and not enough information about any benefits lasting more than 4 weeks.
The uses of wIRA are currently being studied for a variety of medical conditions.7,8 However, there are currently not enough studies to conclude how effective it is for weight loss.
Light therapy may possibly reduce fat in the short term, but studies are small and only follow patients for a few weeks or months. We don’t know if any likely benefit is large enough to be meaningful or how long it might last. So, if you want to lose weight, sustain weight loss, and get fit, we suggest exercise and dieting in a healthy manner. These tried and tested methods are also shown to decrease the overall risk for heart disease and some cancers in the long term.
All articles on our website have been approved by Dr. Diana Zuckerman and other senior staff.
- LED light therapy accelerated healing pain reduction red near infrared. (2015). Retrieved fromhttps://www.elixa.com/light/healing.htm
- Accessdata.fda.gov. (2018). 510(k) Premarket Notification. [online] Available at:https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm
- Jankowski M, Gawrych M, Adamska U, Ciescinski J, Serafin Z, Czajkowski R. Low-level laser therapy (LLLT) does not reduce subcutaneous adipose tissue by local adipocyte injury but rather by modulation of systemic lipid metabolism. Lasers in Medical Science. 2017;32(2):475-479. doi:10.1007/s10103-016-2021-9.
- Thornfeldt CR, Thaxton PM, Hornfeldt CS. A Six-week Low-level Laser Therapy Protocol is Effective for Reducing Waist, Hip, Thigh, and Upper Abdomen Circumference. The Journal of Clinical and Aesthetic Dermatology. 2016;9(6):31-35.
- Duarte FO, Sene-Fiorese M, de Aquino Junior AE et al (2015) Can low-level laser therapy (LLLT) associated with an aerobic plus resistance training change the cardiometabolic risk in obese women? A placebo-controlled clinical trial. J Photochem Photobiol B 153:103–110. https://doi.org/10.1016/j.jphotobiol.2015.08.026
- Möckel F, Hoffmann G, Obermüller R, Drobnik W, Schmitz G. Influence of water-filtered infrared-A (wIRA) on reduction of local fat and body weight by physical exercise. GMS German Medical Science. 2006;4:Doc05.
- Hoffmann G. Principles and working mechanisms of water-filtered infrared-A (wIRA) in relation to wound healing. GMS Krankenhaushygiene Interdisziplinar. 2007;2(2):Doc54.
- Al-Ahmad A, Bucher M, Anderson AC, et al. Antimicrobial Photoinactivation Using Visible Light Plus Water-Filtered Infrared-A (VIS + wIRA) Alters In Situ Oral Biofilms. Hamblin M, ed. PLoS ONE. 2015;10(7):e0132107. doi:10.1371/journal.pone.0132107.