The Spectrum and IR Light
The electromagnetic spectrum (see The Electromagnetic Spectrum and Skin Penetration) is a term used by scientists to describe the range of light arranged according to frequency and wavelength. We can use this tool to see how the various types of light we are exposed to each day affect our skin based upon how deeply the light penetrates, and with how much strength. IR accounts for 50% of a typical person’s exposure each day, as compared to just 7% coming from UVA and UVB.1 Let’s take a look at what exactly IR to determine if it is something we should be concerned about.
As part of the electromagnetic spectrum, infrared light is emitted along with other frequencies including gamma rays, x-rays, UV rays, visible light, microwaves and radio waves. For the purposes of discussing IR’s effect on skin, there are two levels of IR light the average person should know—IRA and IRB.
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IRB, or short wavelength infrared, penetrates just at the epidermal layer. Although this can stimulate some pigmentation, it is not our biggest concern. IRA, or near infrared, goes down to the hypodermis, the place where new skin cells are formed and nutrients are delivered to the skin.2 This deep penetration creates reason for concern because of the extensive damage it can inflict. Recent research suggests that IR radiation induces inflammation, premature skin aging and cancer.3 —three big reasons for concern. What’s even more challenging about exposure to IR is the fact that IR rays come from places other than the sun. Common household appliances such as hair dryers and television remotes also emit rays along with many industrial, high heat generating types of equipment, which most of us are not exposed to on a regular basis.
The good news is that there are ways to protect and counteract the harmful effects of IR radiation. The human body has an amazing ability to adapt and protect. Our bodies react to environmental exposures by using elements found in our own chemistry to fight toxic invaders. In the case of IR exposure, the body utilizes antioxidants to neutralize the free radicals created in the skin after contact with light.
Dietary Antioxidants and IR protection
As a clinical nutritionist, I can’t write an article on skin health without bringing food into the conversation. As usual, there’s an inside-out story here too. Ingesting dietary antioxidants will also offer protection for all kinds of solar radiation. Antioxidants are substances that prevent oxidation, also referred to as oxidative stress. They are nature’s way of protecting cells from damage. In this process of oxidation, free radicals cause damage to the skin tissues and speed up the aging process. Antioxidant-rich foods are plant based and many times referred to as phytochemicals. Scientists at the U. S. Department of Agriculture (USDA) have developed a scale for measuring an antioxidant food’s ability to neutralize free radicals called Oxygen Radical Absorbance Capacity (ORAC). The higher a food’s ORAC score, the more powerful it is in combating age-related degeneration and disease. Foods with the highest ORAC scores include spices, cocoa powder (unsweetened) and richly colored fruits and vegetables.
There are some specific nutrients that have been studied and shown to have strong protective properties against light exposure. Some of the best choices include the following.
Carotenoids. This category includes lutein and zeaxanthin found in dark green leafy veggies and corn; beta carotene found in carrots and sweet potatoes; and lycopene found in cooked tomato products and watermelon.
Vitamin E. This vitamin is found in wheat germ, nuts and seeds.
Vitamin C . Peppers, cantaloupe, citrus, and berries are all great sources of vitamin C.
Polyphenols. Food sources of polyphenols include green tea, dark chocolate, coffee and spices
These foods have been shown to offer antioxidant and light protection when consumed on a regular basis.4 This is yet another great reason for everyone to eat a rainbow of fresh fruits and vegetables every single day. For optimal health, aim for 7-9 servings of fresh fruits and vegetables every day, focusing on eating a variety of colors. This ensures that you have covered all of your bases and in essence creates an “internal sunscreen.”
Topical Protection Against IR Radiation
In terms of a topical skin protectant, the most commonly accepted and widely effective is the use of mineral sunscreens, makeup and lotions with zinc and titanium based ingredients in their composition.3 These compounds reflect the light away from the face, preventing it from penetrating and causing damage. It’s quite simple, yet effective.
In addition to minerals, botanical antioxidants like vitamin C, vitamin E, copper, grape seed extract and lingonberry are effective choices as well. Just about any high quality antioxidant will work to neutralize free radicals, but some do perform better than others.
When it comes to antioxidants, the key factor is to ensure that the ingredient is delivered in a way that prevents oxidation of the compound before it reaches the skin. Sunlight and air can easily neutralize an antioxidant, and this is where emerging ingredient science has brought us better ways to deliver protection to our skin. Innovations in the way the nutrients are encapsulated, packaged and delivered are helping to prevent oxidation and assist with penetration in the skin. In my opinion, the application of topical botanical antioxidants and a mineral sunscreen are a must to counteract the inevitable UV and IR exposure that each of us will face every day.
IR Protection Regulation
The U.S. Food and Drug Administration (FDA) has clearly identified UVA and UVB radiation as dangers to human health and has issued sunscreen guidelines accordingly. This has taken years of collective research and public outcry. At this time, there is no FDA or other public policy statement that helps interpret the dangers of IR and its impact on skin and health. That does not necessarily mean that there is no reason for concern, as sometimes the research takes time and not every study supports what seems like the obvious conclusion. In a 2016 study evaluating the need for IR protection in sunscreens, researchers compared the IRA exposure of steel and glass workers who work in extreme heat to that typical sun exposure. They concluded that the IRA levels were similar and found no notable skin damage in the industrial workers and thereby concluded that IR protection was not needed in sunscreens.5 This is contrary to the conclusions of a 2009 study, which showed that IRA exposure from the sun caused decreased collagen in the skin and damage similar to that of UV light.6 In another, more well designed double-blind, randomized study conducted in 2015, a simple sunscreen formulation was compared to a formula that contained an antioxidant cocktail of vitamin E, C, grape seed and CoQ10. The antioxidant enriched formula showed significant protection against IRA, whereas the sunscreen alone did not. It should be noted that the sunscreen was a chemical sunscreen, not mineral. This is another good reason to choose mineral formulas over chemical, which do not protect as well, and can cause skin inflammation.3
Unfortunately, we can’t always trust research. The challenge is around the quality of the studies being conducted. We need to ask ourselves who is funding the study and what their personal goals might be. We need to consider the structure of the study—was the design smart and scientific? Does it eliminate confounding variables and test the hypothesis accurately? It seems that for every study that draws a positive conclusion, there is one that draws the opposite conclusion.
Future of IR Protection
It takes a great deal of time and money to come to a point where the appropriate amount of financial investment and high level of science is being applied to an issue. Just because research has not been done on IR protection does not mean that it is not a good idea to take preventative measures to protect ourselves, especially if the intervention has no negative consequence. The great thing about combating IR damage is that the preventative steps are things like eating a variety of fruits and vegetables every day and applying natural minerals and botanical products to our skin as protection. We really can’t go wrong by taking those preventative measures. In my mind, infrared protection is not hype, but rather another good reason for great nutrition!
References
- AM Holzer, The Other End of the Rainbow: Infrared and Skin, J Invest Dermatol 130(6) 1496–1499 (2010)
- WM Haynes, CRC Handbook of Chemistry and Physics, 92nd ed., CRC Press: Boca Raton, FL 10.233 (2011)
- S Grether-Beck, A Marini, T Jaenicke and J Krutmann, Effective photoprotection of human skin against infrared A radiation by topically applied antioxidants: Results from a vehicle controlled, double-blind, randomized study, Photochem Photobiol Jan-Feb 91(1) 248-50 (2015)
- E Fernández-García, Skin protection against UV light by dietary antioxidants, Food Funct 5(9) 1994-2003 E1 (2014)
- B Diffey and C Candars, An appraisal of the need for infrared radiation protection in sunscreens, Photochem Photobio Sci 15(3) 361-4 (2016)
- P Schroeder, C Calles and J Krutmann, Prevention of infrared-A radiation mediated detrimental effects in human skin, Skin Therapy Lett Jun 14(5) 4-5 (2009)
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