Sun Protection 101 + Homemade Moisturizing Sunblock Recipe
Published Apr 07 2014 in all-natural sunscreen sunblock recipe, Category_DIY>DIY For The Body, Category_Popular Posts (Home Feature), homemade sunblock, homemade suncreen, moisturizing sunblock, nano-particles zinc oxide, non-toxic sunblock, non-toxic sunscreen, popular, sunblock recipe, sunblock with zinc oxide, suncreen recipe
Sun Protection 101
Sunscreen vs SunblockSunscreen uses organic and inorganic chemical filters to prevent the sun’s rays from penetrating the deeper layers of the skin. Common, sun-filtering ingredients in chemical sunscreens are oxybenzone, avobenzone, octisalate, octocrylene, homosalate and octinoxate. Sunblock uses mineral filters, usually zinc oxide or titanium dioxide, which reflect or scatter the rays to prevent them from reaching the skin.
What is SPF and how does it work?SPF stands for Sun Protection Factor, and refers to the ability of a sunscreen to block ultraviolet B (UVB) rays, which are responsible for burning the surface of the skin. However, SPF does not block ultraviolet A (UVA) rays, which penetrate deep into the layers of the skin, causing skin damage, aging, and skin cancer, specifically, squamous cell carcinoma. When thinking about SPF, most people would probably assume SPF 30 is twice as effective as SPF 15, but that’s actually not the case.
- SPF 15 blocks about 93% of UBV rays,
- SPF 30 blocks 97%,
- SPF 50 block 98%, and
- SPF 100+ blocks about 99.1%.
Do we need sunscreen?There are a couple ways to look at this question: while sunscreen can protect us from cancer-causing UV rays, it may also be changing our behaviour and therefore increasing our exposure to the sun. First, it’s no secret that melanoma is on the rise, and according to the National Cancer Institute, the rate of melanoma cases have tripled in the past 35 years. Although there is speculation as to whether or not the sun is the primary cause of this increase, melanoma can be caused from the overexposure of UVB and, more specifically, UVA rays. The problem with the majority of sunscreens is that they don’t provide adequate UVA protection, and even those that do, are just not enough because avobenzone, the main UVA filter added to almost all chemical sunscreen, breaks down in the presence of sunlight. So yes, we need sunscreen to protect us from the potentially damaging effects of the sun, but sunscreen alone is not sufficient. On the other hand,“problems lie in the behavior of individuals who use sunscreens to stay out longer in the sun than they otherwise would.” Staying in the sun for longer periods of time is increasing our exposure to harmful UVA rays.
Is sunscreen toxic?The BIG question! While many dermatologists are still saying no , and continue to recommend sunscreen “whole heatedly," the Environmental Working Group (EWG) has a different opinion. Sunscreen’s active ingredient comes in the form of chemical and mineral filters. It’s the chemical sunscreens that are causing need for concern. According to the EWG,
In one study, based on a sample of more than 2500 adults and children, 96% of them were detected to have oxybenzone in their systems. Like I mentioned early, higher SPF doesn't necessarily mean better protection from the sun, and the EWG advises to avoid sunscreens with high-SPF because they require higher concentrations of sun-filtering chemicals than low-SPF sunscreens. This study from Harvard states, "The sun protection factor (SPF) you see on the label of sunscreens is misleading. It’s not a measure of total sun protection but of protection against sunburn from UVB light." They advise consumers to look at the ingredients instead of the SPF, and suggest that "the lotions containing zinc oxide and titanium dioxide may be the best bet." There is also speculation as to whether or not the sun is causing this spike in skin cancer, or the over-use of sunscreen itself. This question points to a certain sunscreen ingredient, vitamin A, and the EWG advises to avoid sunscreens that contain Vitamin A (labeled retinyl palminate).
include a combination of three to six of these active ingredients: oxybenzone, avobenzone, octisalate, octocrylene, homosalate and octinoxate. The most problematic of the sunscreen chemicals used in the U.S. is oxybenzone, found in 80 percent of chemical sunscreens. EWG recommends that consumers avoid oxybenzone because it can penetrate the skin, cause allergic skin reactions and may disrupt hormones.
The sunscreen industry adds a form of vitamin A to nearly one-quarter of all sunscreens. Retinyl palmitate is an anti-oxidant that slows skin aging. But federal studies indicate that it may speed the development of skin tumors and lesions when applied to skin in the presence of sunlight.Although no sunscreen seems to be without its risks, sunblocks that use these mineral filters are considered safe, “non-toxic” options. Mineral sunblocks use zinc-oxide and titanium dioxide to reflect or scatter UV rays. They do not permeate the skin, and are stable in the presence of sunlight. Zinc-oxide is the optimal ingredient in sunblock because it provides strong sun protection with few health concerns; it doesn't break down in the sunlight, and offers good protection against UVA rays!
Nano-zinc vs Non-nano zinc. Are they safe?A nanometer is about one hundred thousand times smaller than a human hair. There is concern that zinc nano-particles can be absorbed into the skin and then into the blood stream. Turns out, there are no studies out there proving that nano-particles of zinc oxide can penetrate the human skin. Instead, there’s a lot of research proving quite the opposite (1) (2). Cosmetically, nano-zinc is a better option because when applied, it doesn’t leave behind white film (you know, that life-guard look?) Personally, and based on my own research, I feel comfortable using nano-zinc and have used it in the sunscreen that I’ve made for our trip. If you don’t feel comfortable using nano-zinc, use non-nano zinc which has larger particles. Keep in mind, zinc-oxide doesn’t go without its dangers either. When inhaled, it can damage the lungs and enter the blood stream (so don’t be a silly-billy and wear a mask when making your own).
Personal ConclusionMy personal conclusion around sunscreen is probably pretty obvious by now. After some research, and reading what the EWG had to say about chemical sunscreens, I’ve decided to play it safe opt for sunscreens/sunblocks that:
- Have zinc oxide, or titanium dioxide as the main, sun-filtering ingredient.
- Don't contain oxybenzone.
- Don't contain Vitamin A (labeled retinyl palminate).
- Have an SPF less than 50.
Check out "What Not To Bring On Vacation," and this list, put out by the EWG, to see if your sunscreen passed the test!
How do I make sunscreen?Easy! And Affordable! First you need about 1 Cup of lotion or body butter—I’ve made my own base-lotion, using oils that are naturally high in SPF (recipe below). Then, add zinc oxide to the lotion/butter using the chart below to determine your preferred SPF level.
How much zinc-oxide do I use?For a higher level of protection, you’ll want add 20% of the lotions weight in zinc oxide. For a low to moderate level of protection, you’ll want to add 5-15% of the lotions weight in zinc oxide. For example, the lotion I use as the base for this sunblock is about 8-10 oz (let’s say 9 for this example). If I want a sunscreen that’s about SPF 15, then I’ll add about 1.08oz of zinc oxide. *** Please note, I have NOT scientifically tested these SPF levels in a lab*** Ounces to Tablespoon Converter to help you determine how many tablespoons of zinc add.
What oils naturally contain SPF?Many oils are already naturally high in SPF! So even before adding the zinc oxide to your lotion/butter, it will already have an SPF of at least 2. In my sunblock, I usually use avocado oil because it has an SPF as high as 15! I hope I've provided you with enough information to make your own homemade, moisturizing sunblock with zinc oxide! You'll be lookin' as cool as I do showing up to the beach...with a mason jar full of homemade sunblock ;)
Homemade Moisturizing Sunblock with Zinc Oxide
- 1/4 cup
- 1/4 cup
- 1/2 Cup of one of the oils listed in the "Oils with SPF" chart above, I used avocado oil because that's what I had
- 2-3 Tbsp
- 10-15 Drops Essential Oils (optional)
Zinc Oxide, amount determined in the "Zinc Oxide to Lotion Ratio" chart above. I used a little over 2 Tbsp, to give it an SPF of around 15.
- Melt coconut oil, shea butter and beeswax in a double boiler. To do this, I put the ingredients in a jar, and then put the jar in a simmering pan of water. Remove from heat as soon as they have melted.
- Stir in the ½ cup of oil (eg. Avocado oil)
- Wearing a mask, stir in the zinc oxide. To prevent it from clumping up in the lotion, try sifting it first.
- Thoroughly incorporate the zinc, stirring every few minutes until it cools.
- Once it reaches room temperature, stir in the essential oils if using.
- Store in an airtight container in a cool place or the fridge.
- Use within 6 months.
- The SPF levels are not exact, as I haven't tested them in a lab.
- Remember to re-apply after swimming!
- For babies and young children, the main form of UV protection should be to keep them covered up and in the shade.