Dr Bell R Eapen, MD, Kaya Skin Clinic (THE PRESCRIPTION)
18 February 2011
USING Low density light from LEDS to treat skin isn’t too popular but does have some uses — including an iPhone APP that could zap your zits away
DURING A recent cosmetic dermatology conference, I saw a person lying on a very colourful bed with his eyes blindfolded with dark goggles. On closer inspection, the surface of the bed was made up of an array of LEDs (Light Emitting Diodes) capable of producing light of different wavelengths and I was given a detailed lecture on the various beneficial effects of light on skin.
Though use of light in the treatment of skin ailments dates back to 1500 BC, the use of low density light emitted by LEDs are not very popular and scientific evidence for any noticeable beneficial effect is not very strong. In this article, I will explore the various uses of low intensity light. The discussion below does not apply to UV light emitting devices, Laser or Intense Pulse light devices.
Though manufacturers claim several beneficial effects for light on skin, its effect on acne by far has the strongest scientific backing. Sunlight was long known to improve acne, though humid tropical heat can do just the opposite. Violet light is known to destroy a type of bacteria responsible for the formation of acne. Hence devices emitting violet light may be beneficial in some cases of acne.
Recently a group of researchers introduced an iPhone application capable of producing violet light from the screen and claimed beneficial effects in acne! According to them, an iPhone running this application can work as a zit zapper if held sufficiently close to active pimples. There is no scientific evidence for its
efficacy and the vast majority of the scientific community, including me, believe that the intensity of light from an iPhone screen is insufficient to have any beneficial effect. However, if you are an iPhone user there is no harm in trying it out if you can find it online.
Light in the near infrared spectrum was demonstrated to be useful in the treatment of certain types of scars. It has traditionally been used in the treatment of jaundice in the newborn. It has also been tried in hair loss and wound healing. However manufacturers of LED devices claim several other benefits on the skin. It is claimed to be useful in the treatment of fine lines, blemishes and spots on the skin, redness, flushing and pigmentation. These effects are supposed to be mediated through stimulation of collagen production (fibres that give strength to the skin) and inhibition of melanin synthesis (pigment that gives colour to the skin).
Though small-scale studies have demonstrated a marginal benefit in photo-damaged skin, the evidence is not substantial. Recent studies have failed to demonstrate any benefit on skin redness following laser treatment or radiation dermatitis. Though light of certain wavelengths can stimulate stem cells and fibroblasts (collagen-producing cells in the skin) in-vitro, the intensity of light delivered through skin may be insufficient to achieve these effects.
There are several modifications of light therapy that are very effective in the treatment of various skin diseases including skin cancers. The most popular technique in this category is photodynamic therapy. A chemical that makes skin sensitive to certain wavelengths of light (called photo sensitiser) is applied to the affected area prior to light exposure. This amplifies the effect of light several times and the effect will be directed only to the affected area. Sometimes instead of skin, blood can be exposed to light outside the body and transfused back by a process called photopheresis. Blood can also be irradiated directly inside a vein or inside the nose, where the blood vessels are thin. Photodynamic therapy is a specialised procedure and is mostly used in the treatment of cancers. Photodynamic therapy can be much cheaper than radiation or surgical treatments for cancer. Its only cosmetic use at present is in the treatment of severe acne. I believe the cosmetic indications will widen and it is a very promising technology for the future.
Though manufacturers claim that light therapy is absolutely safe with no pain or downtime, there are some circumstances in which caution is required. Light therapy can cause undesirable consequences in those with photosensitive skin conditions and those taking photosensitising medications. I will describe these conditions and drugs in a later article but suffice to say at this stage that a preliminary assessment by a doctor is advisable prior to any form of light therapy. Light therapy is also used in the treatment of certain sleep disorders and mental health disorders.
Plain light therapy is a relatively safe procedure with few beneficial effects and little side effects. However like most cosmetic dermatology gadgets, the manufacturers/promoters’ claims of life-changing results should be taken with a pinch of salt.
In my next article I will discuss more intense forms of light treatment like PUVA, Narrow band UVB, Low Level Laser Therapy (LLLT) and Intense Pulse Light (IPL).
(Dr Bell R Eapen is a Dubai-based specialist dermatologist with Kaya Skin Clinic. This is a fortnightly
column. Write to him at