Sailing and an active water lifestyle expose skin to more direct and indirect (reflected light from the water, boat decks, and other surfaces) than just about any other outdoor activity. All of this sunlight contains ultraviolet (UV) radiation; the source of sunburn, premature skin aging, and skin cancer, which is the most prevalent type of cancer. When considering a good sunblock, the first goal is to protect your skin from UV and its damaging rays. Secondly, you want to use sunblocks that are safe and do not cause health risks. Lastly, when in the ocean or its tributaries, choose a non-chemical sunblock that will not damage coral and marine life.
UV Rays Explained
The sun emits invisible energy in the form of ultraviolet (UV) radiation which is broken down into two wavelength ranges when talking about sun protection – UVA and UVB. Both contribute to skin aging, wrinkles, and skin cancer.
The vast, vast majority of UV that reaches the Earth’s surface is UVA. It is a long wavelength that is not absorbed by the ozone layer and passes through clouds and window glass. It is always present during daylight hours and penetrates deep into skin layers where it creates free radicals that cause DNA damage to cells, increasing the risk of malignant melanomas. It can produce a quick tan that lasts for days, but not generally a red sunburn.
This is the UV that causes sunburn pain and red skin. Like UVA, it does contribute to skin cancer, wrinkles, and aging, but it does not penetrate glass and is most intense generally between the hours of 10 am – 2 pm. Thus full exposure to UVB is more limited than that of UVA.
Combating the Rays: SPF and Broad Spectrum
When it comes to blocking the harmful effects of UVB with a sunscreen, Sun Protection Factor (SPF) is the measure. SPF is the FDA rating system given to sun blocks as a guide to how long you can stay out in the sun without burning from the effects of UVB (not UVA).
SPF 15 blocks 93% of UVB rays
SPF 30 blocks 97% of UVB rays
SPF 50 blocks 98% off UVB rays
A sunscreen with SPF 15 implies that you can be in the sun 15 times longer than you could with unprotected skin. The higher the SPF, the longer you can stay out in the sun (in ideal conditions – as in laboratory contentions).
By example, if you normally burn after 20 minutes of direct (high noon) sunlight, an SPF 15 would provide you 15 SPF x 20 minutes = 300 minutes of protection before burning. NOTE that these are theoretical protection times for UVB only, and in the field, these times can be greatly reduced by sweating or being in the water; or not reapplying sunscreen as appropriate.
SPF ratings offer no implied protection from the dangers of UVA exposure, and so considering only a sunscreen with high SPF provides many people a false sense of security. The key to sun protection is to be sure your sunblock, in addition to having a high SPF, is ‘Broad Spectrum’. This is the term the FDA assigns to UVA blocking sunblock. Unfortunately, there is not a rating of number scale to Broad Spectrum.
TIP: When choosing a sunblock SPF 15 is the minimum rating you should consider, and SPF 30 is considered best by many dermatologists.
TIP: To block both UVA and UVB, choose a “Broad Spectrum’ sunblock with an SPF of 15 – 50. The bottle will read “Broad Spectrum SPF [value]’
Don’t Be Fooled by High SPF
Sunscreens with an SPF above 50 may tempt you to stay in the sun too long. A higher SPF may suppress sunburn, but not necessarily other skin damage. Stick to SPF 15-50 and reapply frequently.
Waterproof, Water-Resistant and Very Water-Resistant Sunscreens
Waterproof sunscreens do not exist and are not allowed to be labeled as such by the FDA. Water-resistant labeled sunscreens will maintain their SPF rating up to 40 minutes while swimming or sweating. Very-Resistant means the SPF will be maintained for 80 minutes.
TIP: If you are swimming or sweating, reapply sunscreen more frequently.
Sunscreens contain filters that reflect or absorb UV rays. There are two main types:
Organic (chemical) sunscreens are absorbed into the skin where they absorb UV radiation and convert it to a small amount of heat. They can contain a number of US approved chemicals, some of which carry health risks to the wearer and to marine life as they exist out of the tube, and can change chemical composition in sunlight to become a health risk.
Inorganic (mineral) sunscreens are not absorbed and remain on the surface of the skin where they reflect sunlight away. They contain inert ingredients and do not change composition when exposed to sunlight. These ingredients are either zinc oxide (good for UVA & UVB) or titanium oxide (good for blocking UVB, but not as good with UVA). These are the best UV blocking and safest sunscreen ingredients available and are widely recommended by dermatologist.
TIP: Clear zinc or titanium-based sunscreens use a micronized ingredients that make them more translucent, but the smaller particle size is less efficient at blocking UVA. For the best protection, stick with zinc and titanium sunscreens that go on white.
TIP: Mineral-based sunscreens that are a blend of zinc and titanium are the absolute best UV blockers, as each ingredient has differing blocking abilities through the UVA – UVB wavelength spectrum. In combination, they block basically all wavelengths throughout the spectrum.
Sunscreen Ingredients to Avoid
Oxybenzone & Octinoxate are approved by the FDA for use in sunscreens, but they are proven hormone disrupters in humans. They are banned in some coastal states as they are very toxic to coral (bleaching) and mutate marine life.
Paraben Preservatives mimic estrogen, have been found in breast cancer tumors and stimulate the growth of breast cancer cells in the lab. With many paraben-free sunscreens available, and more and more manufacturers eliminating them every day, it’s easy to skip these worrisome chemicals.
Retinyl Palmitate (Type of vitamin A) is an antioxidant, but in sunlight, it can form free radicals that damage DNA and can lead to cancer.
TIP: The Environmental Working Group (EWG) is an internationally recognized that rates sunscreens for effectiveness in blocking UVA & B, and health safety. We encourage you to visit their product rating library where you can look up almost all sunscreen products and review their risk rating: www.ewg.org/sunscreen/about-the-sunscreens
TIP: For more information on the Hazard Score of UV blocking ingredients found in sunscreens, visit the EWG Active Ingredient Toxicity: https://www.ewg.org/sunscreen/report/the-trouble-with-sunscreen-chemicals/
Additional Sunscreen Tips
Spray sunscreens are not recommended. Inhalation of chemical sunscreens during application leads to these chemicals entering the bloodstream. Also, you will have a difficult time ensuring you are getting the amount of coverage on your skin that is needed. Lastly, they are wasteful, as a fair amount of the product floats away in the air when spraying.
Once you have chosen a safe and effective sunscreen, you must apply enough of it to ensure there is a sufficient layer over all of your exposed skin. Be very generous when applying. Most people use only half or less of the needed amount to properly protect themselves. Slather it on.
Frequency – It is recommended that you reapply sunscreen fully every two house to maintain full protection. If you are in the water or sweating, a more frequent application may be necessary.
Insect Repellent Additives
While application and reapplication of sunscreen should happen every two house; while insect repellent (and the chemical ingredients in them) are only needed when insects are present. Skip sunscreens containing insect repellent – if you need bug spray, buy it separately and apply it only as needed.
Sunscreens generally have a shelf life of 1-3 years. Pay attention to bottles labeling the expiration date. An expired sunscreen may not have the intended strength or sun protection and could irritate your skin.
Conclusion: What is the Most Effective and Safest Sunscreen for Watersports?
Active ingredients of both zinc oxide and titanium dioxide that are not micronized (goes on white at first), in liquid or cream form (not a spray). Free of Retinyl Palmitate antioxidants and Paraben preservatives; and free of Oxybenzone and Octinoxate organic (chemical) UV absorbing ingredients. This will provide you with safe, Broad Spectrum and high SPF (30+) protection from UVA and UVB. Chose either a water-resistant or very water-resistant formula (zinc oxide and titanium dioxide are by default usually water resistant).
Sunscreens of this type are the most effective at blocking both UVA & UVB, have the least health risks to the person using it, and are safe for coral and marine life.