UVA and UVB
The two main kinds of ultraviolet light emitted by the sun are UVA (Ultra-Violet A) and UVB (Ultra-Violet B). Sunscreens are applied to protect the skin against these rays.
- UVA (Ultra-Violet A): are the sun’s rays that penetrate the skin deeply. They are the principal causes of wrinkles and sun-induced aging. While they do not often cause sunburn, some recent research indicates that UVA sometimes increases UVB’s cancer-causing effects, and also causes skin cancer.
- UVB (Ultra-Violet B) are the suns rays that strike the surface of the skin and therefore cause sunburn. They are considered the major cause of skin cancers.
What is SPF?
SPF or Sun Protection Factor is the time that protected skin would take to burn as compared to an unprotected skin expressed as a number. For example, if a person whose skin burns after 10 minutes exposure to the sun wore a sunscreen with an SPF of 3, it would take him 30 minutes to start to burn. If he wore a sunscreen with SPF60, it would now take him 60 times the original amount of time for him to start to burn i.e. 60 minutes.
How does a Sunscreen work?
- Sunscreens act as a barrier to solar ultraviolet radiation
- They are said to reduce the chances of developing sunburn and the risk of skin cancer.
- Ingredients that exclude UVA rays include oxybenzone, avobenzone or Parsol 1789
- Ingredients that exclude UVB rays include cinnamates and salicylates
- Ingredients like zinc oxide which is a natural material, deflects light and this and titanium dioxide are both used in highly effective sunscreens.
- Some sunscreen products also purport to contain antioxidant products that are said to prevent and halt skin damage.
Broad Spectrum Sunscreens
- Broad Spectrum sunscreen protects the wearer against UVA and UVB rays. It does not however ensure protection against all UVA rays.
- If the sunscreen is broad spectrum with an SPF of over 15 it is likely to shield the wearer against UVB and short UVA rays
- If it contains avobenzone, zinc oxide, or titanium dioxide it is more likely to be effective against all UVA rays.
Difference between Sunscreen and Sun Block
The difference between sunscreen and sunblock is that sunscreen is made of chemicals that absorb UV rays and sunblocks on the other hand deflect them. New sunscreen formulae have been created in order to effectively absorb more UVA rays which earlier recipes were unable to do. Chemicals like avobenzone (Parsol 1789) are able to absorb all UV lengths.
Sunscreens chemically absorb UV rays, sunblocks physically deflect them. Sunscreen has long blocked UVB effectively, but until recently provided less UVA protection. New ingredients such as octylcrylene and the benzophenones have improved sunscreen's defenses against shorter UVA rays, and the revolutionary chemical avobenzone (Parsol 1789) works against all UVA wavelengths.
Sunblocks have also improved. New preparations such as micronized titanium dioxide are less conspicuous on the skin and offer substantial protection against both UVA and UVB.
Sunscreen -- When? How much? How often?
- Use sunscreen if exposure to the sun is going to be in excess of 20 minutes
- Use sunscreen on cloudy days as well since 80% of UV rays come though in spite of the clouds.
- Apply sunscreen 30 minutes before sun exposure, reapplying every two hours. Reapply more often if swimming or perspiring excessively. Ensure that all exposed portions of the body are well covered.
- The choice of sunscreen is a matter of personal preference. There a wide array of products to chose from. Lips also needed to be protected, so lip salves with sunscreen are recommended. Also, a broad spectrum sunscreen with an SPF of 30 and more are most effective. Waterproof sunscreens are best for the outdoors.
Different types of Sunscreen Products
Commercially available sunscreen products include --
- Sunscreen Lotions, Creams, Gels, Sprays and Powders: Sunscreen lotions are best when exposure is prolonged. These products contain titanium dioxide. Sunscreen creams are useful for less intense sun exposure. Sprays and gels are also available. The latter can be worn under makeup.
- Sun Blocks
- Eye and Lip Sunscreens
- Hand Sunscreens: hands show ageing and sun damage most easily. They are amongst the most exposed parts of bodies.
- Antioxidant Sunscreens
- Makeup with Sunscreens: Some make up bases are very conveniently available in combination with a sunscreen.
- Tinted Sunscreen: These products are excellent for people who want to look bronzed without harming their skins.
- Water Resistant Sunscreen: Water resistant sunscreen is reputed to protect the skin for 40 minutes in the water and water proof ostensibly lasts 80 minutes.
- Sun Defense Kits: These kits package several products that can be used in combination with each other together
- Sunscreen for Babies and children:
- Sunscreen Wipes
- Sunscreens for Sensitive Skin
Do we really need to wear sunscreen?
There is a parallel school of thought that rubbishes the need to wear sunscreen. Their contention is as follows
- Cancer prevention by wearing sunscreen is a myth.
- It is the sunscreens themselves that cause cancer.
- Sunscreen companies donate a percentage of sales to cancer research and organisations like the American Cancer Society who in turn perpetuate this fallacy.
- Sunscreens contain toxic chemicals that are absorbed by the skin which in turn cause the disease.
- Sunscreens also block the absorption of Vitamin D which prevents cancer in the human body.
- Eating for sun protection: Supporters of sunscreen say that it prevents sunburn. It is a proven fact that mere sun exposure does not cause sunburn. This is accelerated by inadequate nutrition largely in the form of low antioxidants intake. An increase in the intake of berries and micro-algae like spirulina helps build immunity to sunburn.
The big question is “Is sunlight really bad for us?” If so, how have human beings lasted so long, and how is it that all animals need sunlight to grow and prosper?
Sunscreen ingredients that hurt
- Benzophenone is easily absorbed by the skin.
- This chemical is present in most sunscreens. It tends to cause skin irritations and allergies.
- Benzophenone- 3 behaves like the hormone oestrogen and increases the numbers of oestrogen sensitive breast cancer cells. It also has the potential to disrupt the hormonal balance of users.
- Other products that harm include
- Homosalate and octyl-methoxycinnamate (also called octinoxate): this also acts like oestrogen in test tubes
- Padimate-O is a derivative of PABA. PABA was earlier widespread in sunsreens but caused irritations and was discontinued. Padimate-O is said to cause damage to the DNA which could cause cancer.
- Titanium dioxide application also indicates DNA damage. These last two are as yet only lab and not human and living animal experiments
- Diethanolamine (DEA) and associated compounds like triethanolamine or TEA may lead to cancer causing compounds if the sunscreen contains nitrites. The FDA agrees that this is possible and is attempting to examine this. They do not as yet acknowledge risk to users.
- Parabens including butyl-, ethyl-, methyl-, and propyl-paraben are used as preservatives in almost all sunscreens. They, like benzophenone act like oestrogen and therefore carry similar risk. Not using them means cutting out all sunscreen use.
- Synthetic fragrances could cause allergies or asthma.
- Environmental damage
- Titanium dioxide production is a chlorine based process that results in environmental damage and endangers humans and wildlife.
- Zinc mining causes enormous damage to the environment. The Red Red Dog mine in Alaska, is instrumental in polluting enormous areas with toxic heavy metals like cadmium, lead and zinc. Acid is used as part of the process to separate the metal from the ore. This has permanently polluted the area and the aquifer.
- Use sun block rather than sunscreen. Sunblock lies on top of the skin rather than getting absorbed by it.
- Do not used micronised titanium products. Smaller particles of titanium tend to enter the skin and cause damage. Stick with the un-micronised stuff.
- Use broad spectrum sunblocks.
- Eat for sun protection: load up on natural anti-oxidants in your diet. Include fresh berries, green tea, spirulina and as many other natural anti-oxidants as you can.
- Cover up in the sun: the clothing, hats and glasses with afford lots of protection.
- Use natural sunscreens like shea butter.
- Use natural anti tanners like real lemon juice.
- Sunscreen Advice
- Making sense of Sunscreen products
- More about Sunscreen
- SPF, UVB and UVA protection explained
- Sunscreen FAQs
- Making Sense of Sunscreen Products on MedicineNet
- Web definitions for sunscreen
- A Consumer Guide for Avoiding Nano-Sunscreens
- Nanotechnology and Sunscreens
- For more on melanomas and how to do a self examination, read Melanoma (Skin Cancer)Symptoms, Treatment, Diagnosis and Signs on MedicineNet.
- The sunscreen myth: How sunscreen products actually promote cancer.
- Sunscreen and Sunblocks
International Safer Sunscreen Brands
The author and website does not take any responsibility for the products listed here. This is not an endorsement. It is merely an indication that several products in the market claim to be less harmful that some others. Users are advised to undertake independent research before using any of these products.
The source for all products listed below is : National Geographic
- Aubrey Organics Natural Sun SPF 25 Green Tea Protective Sunscreen, contains PABA and titanium dioxide.
- California Baby SPF 30+ Sunscreen, contains micronized titanium dioxide and is benzophenone-free
- Clinique City Block (contains micronized titanium dioxide)
- Devita Daily Solar Protective Moisturizer contains micronized zinc oxide. See Holistic Beauty
- Dr. Hauschka Sunscreen Stick SPF 30 contains micronized titanium dioxide,
- Epicuren Discovery Zinc Oxide Sunscreen contains micronized zinc oxide. Refer to The best of Beauty in Harmony
- JASON Naturals Earth's Best Organic Sunblock, Chemical Free SPF 30+ zinc oxide and titanium dioxide, Drugstore
- Lavera sunscreen products zinc oxide and titanium dioxide,
- U.V. Natural SPF 30 contains coated micronized zinc oxide. Visit Isabella
- Vanicream SPF 35 contains micronized zinc oxide and titanium dioxide. Visit Coolibar
Protective moisturizers and makeup
- Juice Organics Tinted Moisturizer SPF 30, titanium dioxide
- Bare Escentuals' i.d. bareMinerals Powder Foundation SPF 15, which bears the Skin Cancer Foundation Seal of Recommendation. Visit Sephora
Protect lips from over exposure to the sun and lip cancer. If the lip balm contains octinoxate and oxybenzone, it may increase the risk of lip cancer if licked off and swallowed.
- Aveda's Lip Color Concentrate contains titanium dioxide
- Lifeguard's Choice Lip Balm from Burt's Bees
- L'Occitane Pure 100-percent Shea Butter and Tinted Shea Butter Balm
Easing sunburn pain
- Aubrey Organics'Pure Aloe Vera Gel
- Little Moon Essentials' Lift-Off after-sun lotion
- Lavera Basis After Sun Lotion for sensitive skin