thuong2lan
Newbie
As a Dermatologist and skin cancer expert, I often cringe when I attend classes. The discomfort stems from observing too many sunburns and knowing what that portends in the future. I have been practicing dermatology for 21 years and treat skin cancers daily. The wounds they cause can be devastating, disfiguring, and occasionally fatal. One in five Americans will develop skin cancer by the age of 70. The month of May is skin cancer awareness month so for my shooting colleagues, here is what you need to know. This is informational only and knowledge is power. If you have a personal situation, then I will not be able to comment on it without seeing you as a patient.
There are three main types of skin cancer: basal cell cancer (BCC), squamous cell cancer (SCC) and malignant melanoma (MM). All cancers are malignant. Malignant = bad. All skin cancers destroy normal tissue. Untreated, they eventually form wounds that fail to heal, bleed, crust, and grow. Nerves, muscles, and even bone can be destroyed by the physical extension of the skin cancer. I have treated patients with their noses, lips, eyelids, and ears eaten away by skin cancers. Besides destroying local tissue, skin cancers may also spread inside the body to lymph nodes and beyond. This gets serious and patients may die from internal spread. Of the three skin cancers above, SCC and especially MM can spread internally.
The sun has three main rays: UVA, UVB, and UVC (UV = ultraviolet). UVC is extremely dangerous but is blocked by the ozone layer from reaching Earth. Both UVA and UVB reach our surface but at different levels and cause different biologic effects.
UVA has a longer wavelength and can penetrate through windows and clouds. It penetrates most deeply into the skin and will cause suppression of the immune system in the skin (more on that later). It also damages the elastic fibers over time and causes accelerated skin aging (loose wrinkly skin, discoloration). UVA does not cause skin cancer per se but it makes it easier for skin cancer cells to grow. Your skin immune system is pretty good at identifying abnormal cells and eliminating them. UVA, however, suppresses your skin immunity and weakens your ability to destroy the abnormal cells, thereby allowing them to grow unchecked. UVA intensity is consistent all year round and does not vary too much with seasons.
The role of your immune system is paramount in your fight against skin cancer. Organ Transplant Recipients (OTR) are patients with implanted organs from others (kidney, lung, heart, etc) OTR have their immune system severely suppressed so that they do not reject their organs. As a results, OTR develop SCC at 100 times the rate of patients who do not have a weakened immune system.
UVB has a shorter wavelength than UVA and penetrates only the top layer of our skin (epidermis). This is the ray that causes skin cancer (by inducing DNA mutations that lead to abnormal growth) and sunburns. UVB intensity will vary with seasons, more intense in the summer and less in the winter. High altitude increases your exposure to both UVA and UVB.
If you are near water or reflective surface, you are getting UVA/UVB from above as well as at least 50% reflection from below.
How do you know if you are getting sun damage? After some time in the sun, if your skin is red or tanned then sun damage (cellular DNA damage) has occurred. Any redness from sun exposure reflects cellular damage. Furthermore, no tan is a good tan because your body generates pigment (tan) only as a response to cellular injury. Some people cannot tan genetically (red or blonde hair, fair skin, freckly). These persons are at greatest risk of skin cancer. No one is immune. I have treated skin cancer patients who are Caucasian, East-Asian, Central Asian, Southeast Asian, Middle-Eastern, Hispanic, African-American. No one is immune.
Tanning beds deserve special mention. The lightbox in a tanning parlor is concentrated intensely with UVA and very little UVB. That is why some parlors advertise that they “do not contain the rays that cause skin cancer.” Technically they are correct since little to no UVB exposure occurs. However, you are getting concentrated doses of UVA, which knocks out your skin immune system and indirectly increases your skin cancer risk. Usage of tanning beds before age 35 can increase your risk of melanoma by 59 percent. Even one indoor tanning session can increase users’ risk of developing melanoma by 20 percent, squamous cell carcinoma by 67 percent and basal cell carcinoma by 29 percent. Basically, if you use tanning beds then please stop.
In regards to Vitamin D production and UV exposure, all you need is about 15 minutes exposure on several times a week to generate all the Vit D you need (which can also be achieved with diet and supplements).
SUMMARY OF UV RADIATION EFFECTS
Most shooters I see in classes are young (50 years old or younger). The ravages of skin cancer begin at different ages but generally the older you get, the more problems you have with skin cancer. You may not feel it now and think nothing will happen to you, but you will dearly regret it later. The exception is Melanoma in that it often strikes younger patients (<50).
Remember, one in five Americans will develop skin cancer by the age of 70. If you had a pistol with a one in five chance of malfunctioning or blowing up in your face, would you use it? If you had a one in five chance of getting assaulted by being somewhere, would you do everything you can to not go there?
Remember that the damage is cumulative. Every sunburn counts and adds up to your skin cancer risk. It is never too late to protect yourself from UV damage at any age.
Now that you are more aware of UVR and skin cancer risks, what can you do?
There are three main types of skin cancer: basal cell cancer (BCC), squamous cell cancer (SCC) and malignant melanoma (MM). All cancers are malignant. Malignant = bad. All skin cancers destroy normal tissue. Untreated, they eventually form wounds that fail to heal, bleed, crust, and grow. Nerves, muscles, and even bone can be destroyed by the physical extension of the skin cancer. I have treated patients with their noses, lips, eyelids, and ears eaten away by skin cancers. Besides destroying local tissue, skin cancers may also spread inside the body to lymph nodes and beyond. This gets serious and patients may die from internal spread. Of the three skin cancers above, SCC and especially MM can spread internally.
The sun has three main rays: UVA, UVB, and UVC (UV = ultraviolet). UVC is extremely dangerous but is blocked by the ozone layer from reaching Earth. Both UVA and UVB reach our surface but at different levels and cause different biologic effects.
UVA has a longer wavelength and can penetrate through windows and clouds. It penetrates most deeply into the skin and will cause suppression of the immune system in the skin (more on that later). It also damages the elastic fibers over time and causes accelerated skin aging (loose wrinkly skin, discoloration). UVA does not cause skin cancer per se but it makes it easier for skin cancer cells to grow. Your skin immune system is pretty good at identifying abnormal cells and eliminating them. UVA, however, suppresses your skin immunity and weakens your ability to destroy the abnormal cells, thereby allowing them to grow unchecked. UVA intensity is consistent all year round and does not vary too much with seasons.
The role of your immune system is paramount in your fight against skin cancer. Organ Transplant Recipients (OTR) are patients with implanted organs from others (kidney, lung, heart, etc) OTR have their immune system severely suppressed so that they do not reject their organs. As a results, OTR develop SCC at 100 times the rate of patients who do not have a weakened immune system.
UVB has a shorter wavelength than UVA and penetrates only the top layer of our skin (epidermis). This is the ray that causes skin cancer (by inducing DNA mutations that lead to abnormal growth) and sunburns. UVB intensity will vary with seasons, more intense in the summer and less in the winter. High altitude increases your exposure to both UVA and UVB.
If you are near water or reflective surface, you are getting UVA/UVB from above as well as at least 50% reflection from below.
How do you know if you are getting sun damage? After some time in the sun, if your skin is red or tanned then sun damage (cellular DNA damage) has occurred. Any redness from sun exposure reflects cellular damage. Furthermore, no tan is a good tan because your body generates pigment (tan) only as a response to cellular injury. Some people cannot tan genetically (red or blonde hair, fair skin, freckly). These persons are at greatest risk of skin cancer. No one is immune. I have treated skin cancer patients who are Caucasian, East-Asian, Central Asian, Southeast Asian, Middle-Eastern, Hispanic, African-American. No one is immune.
Tanning beds deserve special mention. The lightbox in a tanning parlor is concentrated intensely with UVA and very little UVB. That is why some parlors advertise that they “do not contain the rays that cause skin cancer.” Technically they are correct since little to no UVB exposure occurs. However, you are getting concentrated doses of UVA, which knocks out your skin immune system and indirectly increases your skin cancer risk. Usage of tanning beds before age 35 can increase your risk of melanoma by 59 percent. Even one indoor tanning session can increase users’ risk of developing melanoma by 20 percent, squamous cell carcinoma by 67 percent and basal cell carcinoma by 29 percent. Basically, if you use tanning beds then please stop.
In regards to Vitamin D production and UV exposure, all you need is about 15 minutes exposure on several times a week to generate all the Vit D you need (which can also be achieved with diet and supplements).
SUMMARY OF UV RADIATION EFFECTS
- It indirectly promotes skin cancer by weakening your skin immune defenses against abnormal cells
- It directly causes DNA damage to your cells, which has short term and long term injury. Short term, DNA damage leads to redness and sunburns that can be uncomfortable. Long term, DNA damage may lead to mutations that cumulatively can add up and can cause skin cancer.
- It dramatically accelerates your skin aging: more wrinkles, more fragility and thinness, more bruising on the arms, more discoloration, more itching and dryness.
Most shooters I see in classes are young (50 years old or younger). The ravages of skin cancer begin at different ages but generally the older you get, the more problems you have with skin cancer. You may not feel it now and think nothing will happen to you, but you will dearly regret it later. The exception is Melanoma in that it often strikes younger patients (<50).
Remember, one in five Americans will develop skin cancer by the age of 70. If you had a pistol with a one in five chance of malfunctioning or blowing up in your face, would you use it? If you had a one in five chance of getting assaulted by being somewhere, would you do everything you can to not go there?
Remember that the damage is cumulative. Every sunburn counts and adds up to your skin cancer risk. It is never too late to protect yourself from UV damage at any age.
Now that you are more aware of UVR and skin cancer risks, what can you do?
- Avoid un-protected sun exposure, especially during the peak hours between 10AM-4PM.
- Use sun protection measures, including:
- Sunglasses: UV damage to your eyes will accelerate cataracts and will cloud your vision as you age. Almost all eye-pro are also protective against UVR but always make sure.
- Hats: Baseball caps protect only your forehead. You need a hat with at least a four-inch brim all around to also protect your ears. If you only wear a baseball cap, then you need sunscreens on your ears and a neck gaiter.
- Sun protective clothing: Scarves, bandannas, pull on sleeves, long sleeves, gloves- all of these will help. To be UV protective, they either have to be woven dense enough that you cannot see the sun through them or be specially treated so that they block the sun. I see sun protective labels on many clothing lines such as Columbia, Coolibar, Sun-Precautions, SA company (they make great sleeves and neck gaiters for fishermen). What is not protective is a regular T-shirt, which only has an SPF 8 protection. If you wear shorts, then you need to apply sunscreens on your legs. Sprays again work best for hairy legs.
- Antioxidants: Oxygen radicals are unstable molecules that cause DNA damage and cellular damage. They are generated by inflammation and our bodies are always producing it. UVR exposure generates a lot of oxygen radicals. Generally, it is good to reduce oxygen radicals as much as possible. Applying antioxidant creams on the skin and taking antioxidant supplements are also helpful. There is a product called Heliocare that is made from the fern (Polypodium leucotomos) in South America. It significantly reduces the inflammation from UVR exposure and is a great adjunct to sunscreen. I tell my patients that if sunscreens are your seatbelt, then heliocare is your airbag. I take heliocare personally.
- Sunscreens: Technically, you can use anything that is SPF 30 or greater. I recommend SPF 50 or more because most people do not apply enough. Make sure that it covers both UVA and UVB. Sunscreens are either chemical or physical in nature. Physical sunscreens contain ingredients zinc oxide and or titanium dioxide. Chemical sunscreens contain things like avobenzone, homosalate, octisalate, oxybenzone, etc. I like the physical ones better. they are less likely to irritate and less likely to wash off. There have been some press about chemical sunscreens causing uterine tumors in rats when the rats were “fed” oxybenzone at very high doses. Unless you are a rat, have a uterus, and plan to engorge yourself buffet style and eat oxybenzone, then you should be ok. Physical sunscreens have no issues. Personally, I use Neutrogena’s Pure & Free Baby Mineral Sunscreen Stick (SPF 60), which is very convenient and easy to reapply. It applies like a stick deodorant, so it does not get your hands greasy. It is good for sensitive skin and is PABA free (preservative). Sprays are good for the arms and legs, especially if they are hairy. Elta MD is a line of sunscreens that have special formulations for sensitive skin, acne prone skin, oily skin, or patients who sweat a lot. They are usually only available at Dermatologist’s offices. Make sure you reapply every four hours to maintain the efficacy, especially if you are sweating or wet. Even with the best sunscreens, some UVR always gets through. Therefore taking heliocare as above and using sun protective clothing is recommended.
