Why do acne scars turn red by chance?

Light therapy for acne shows neither benefit nor harm

Almost everyone will experience acne at some point in their life. In addition to health insurance benefits, there are also services that you have to pay for yourself, such as light therapy. In a current analysis, the scientists of the IGeL monitor do not see any indications of additional benefit or harm for therapy with red and blue light. The assessment is therefore “unclear”.

Especially at a young age, people are often affected by acne with purulent pustules on the face and body. Hardly anyone is spared, the suffering is sometimes enormous. As a possible remedy, light therapies are also offered as individual health services, IGeL for short. An evaluation of the current scientific literature by the scientific team of the IGeL-Monitor has now shown that there is insufficient evidence of the advantages or disadvantages of therapy with red and blue light compared to standard therapy. Since the benefit and harm are balanced, the assessment is “unclear”.

One speaks of mild acne when the skin has an above-average number of blackheads, of moderate acne when red nodules and purulent pustules can also be seen, and finally of severe acne when the skin is covered with inflamed nodules and pustules. There can be various reasons for acne: The most common cause is probably male sex hormones, which girls also produce more intensely during puberty. Other causes could be increased sebum production and a colonization of the excretory ducts of the sebum glands with bacteria as well as a cornification disorder of the excretory ducts. The following risk factors are also discussed: hereditary predisposition, ethnicity, diet, sunlight, social status, hygiene, obesity and smoking.

There are various options for acne therapy. The current guideline of the German Dermatological Society of 2010 "Treatment of Acne" primarily recommends drugs that are applied to the skin. In more severe cases, certain drugs can also be taken and thus have an effect on the entire organism. The skin damage can additionally or alternatively be treated with peeling, cleansing and light. In light therapy, blue light is supposed to kill pus bacteria and red light is supposed to improve blood circulation in the skin. A light therapy session usually costs between 5.30 and 15 euros. Usually eight sessions are offered over four weeks.

The scientists at the IGeL monitor wanted to know what the benefits and harms of therapy with red and blue light for acne. They found nine scientific studies on this. The studies looked at the benefits of light therapy alone or light therapy in addition to treatment with gels. There were isolated slight advantages of light therapy. However, the scientific team does not consider this to be an indication of any benefit. The reason: You can't really rely on the results of the studies. For example, the studies lack information on whether the doctors knew which study participants were receiving light therapy and which were in the control group without light therapy. So you don't know whether they were “blinded”. This is important because doctors who know that study participants are being treated are more inclined to see the treatment as being successful. The information on the possible damage was also unreliable. Overall, the IGeL-Monitor's scientific team therefore sees neither sufficient evidence of benefit nor harm.

The guideline of the professional association comes to the conclusion that light therapy can at least be considered. According to the guideline, however, patients should not have too much hope: “A direct effect on comedones (blackheads) is not to be expected. More severe acne courses do not improve. "


At www.igel-monitor.de, insured persons receive evidence-based assessments of so-called "self-pay benefits". The non-commercial internet platform was developed by the Medical Service of the National Association of Statutory Health Insurance Funds (MDS). The MDS advises the National Association of Statutory Health Insurance Funds in all medical and nursing questions that are assigned to it by law. He coordinates and promotes the implementation of the tasks and the cooperation of the Medical Services of the Health Insurance (MDK) at state level in medical and organizational issues.

The IGeL “light therapy for acne” is the 47th achievement that the IGeL-Monitor has meanwhile rated. So far there have been the following reviews:

positive 0
tends to be positive 3
unclear 19
tends to be negative 20
negative 4
in revision 1

Four other IGeL were not assessed, only discussed.

To evaluate: light therapy for acne

Press contact:

IGeL monitor
Dr. Christian Weymayr
Tel .: 01577 6811061
Email: [email protected]