Now that the summer months are rolling in, we thought it would be a good time to talk about a hot topic (pun intended): natural homemade sunscreen.
Natural sunscreen, sunscreen formulations and SPF recipes are something we are frequently asked about. Just the other day, someone asked me to provide the amounts of zinc oxide required to make up a formula with a specific SPF. As we will find out, creating a sunscreen with a verified SPF is not quite this simple. But you can still make up a cream with sun protection properties using natural ingredients.
So far I have refrained from posting any blog or recipes relating to sunscreen or SPF ingredients as it is in all honesty something that I am on the fence about personally. SPF needs to be tested against a standard and because natural products are just that, natural and therefore variable, it would be misleading to say that there is an inherent specific sun protection factor attached to any particular natural product. We at Essentially Natural pride ourselves in absolute honesty with all our products and ingredients and we are proud to share our knowledge through free informational blogs and recipes every week. So we want to share anything that will help you in your natural journey, but we also want you to have all the facts before you forge ahead and create a sunscreen in the belief that it will have a certain SPF. Natural sunscreen ingredients are something we absolutely get behind, but we are not claiming any of the ingredients we sell have a specific SPF.
Instead, we want to open up a conversation on the topic of natural sunscreen as it is definitely worthy of discussion. So please feel free to engage and post your thoughts in the comments.
As always, I’m going to take the scientific approach and lay out all the facts. So keep reading!
What Exactly are UV Rays and SPF?
There are a number of natural products that are used in natural sunscreen formulations as they can protect against the sun. Some of them include zinc oxide powder, red raspberry seed oil, carrot root extract and sea buckthorn berry oil among others. But before we jump into natural sunscreen ingredients, it is important to understand what exactly sun protection is and what we want to protect from. So here are the basics on sun rays.
Sun light covers a large portion of the electromagnetic radiation spectrum including infrared, visible and ultraviolet light - thankfully much of this radiation is filtered out by the ozone layer and our atmosphere. We see these rays as light during the day, and we can also feel them as warmth on our skin. The most damaging to skin are the ultraviolet or UV rays. UV rays come in three subgroups, UVA, UVB and UVC. UVC rays don’t make it through the earth’s atmosphere but UVA and UVA do.
Most of the light that reaches earth is from UVA rays, which are able to penetrate deeper layers of the skin and are responsible for premature aging, wrinkle formation, formation of free radicals and DNA damage. UVA rays stay constant all year round and are dangerous because they penetrate through clouds and glass. Did you know? UVA rays were once thought to be safe and were used in tanning beds. We now know they can cause premature aging and skin cancer.
UVB rays are responsible for tanning and sunburn, skin damage and certain forms of skin cancer, but are also necessary for Vitamin D production in mammals. The amount of UVB rays increases during the summer and is particularly potent from late-morning to mid-afternoon (which is why it is recommended to stay out of the sun from 11am - 3pm). Fortunately UVB rays can be filtered and do not pass through glass.
So what is Sun Protection Factor? SPF is actually a standard for UVB protection only, and is tested in a lab under set conditions to meet the standard. Essentially, the SPF number tells you how long UVB rays would take to redden and burn your skin if you apply the product exactly as directed, compared to the amount of time it would take to burn with no sunscreen applied. Therefore if a sunscreen claims, for example, an SPF of 40, then it will have been tested and proven to take 40 times longer to burn compared to no sunscreen.
UV protection works by absorbing, reflecting or scattering UV rays. In order to achieve this, sunscreens make use of chemical filters that penetrate the skin and absorb the rays, and physical filters which sit on top of our skin and reflect the sun’s rays, protecting our skin.
Organic/Chemical Filters vs Inorganic/Physical Filters
When it comes to sun protection, there are two types of active ingredients: chemical filters and physical filters.
Chemical sunscreen filters are also called organic filters but they have nothing to do with organic farming and organically sourced ingredients. The term organic here refers to organic chemistry, basically anything containing the element carbon, and the opposite of inorganic chemistry. Chemical filters penetrate the skin and absorb the incoming rays of the sun. This penetrating action of chemical filters is also the root of problems in conventional sunscreens, as it can reach deep into our bodies. Studies have found sunscreen elements in breast milk and urine and they can be linked to instances of endocrine disruption.
Physical or inorganic filters are often also called mineral filters as the minerals zinc oxide and titanium dioxide are the most common ingredients. Physical filters reflect and scatter the sun’s rays. The minerals zinc and titanium come in non-nano particles sizes and nano sizes. Non nano are obviously not on the nano size scale (which are microscopically small at 1×10−9 m), and therefore are not absorbed by the skin, but rather sit on top of the skin, performing the job of reflecting the sun’s rays. They may leave a white residue so many consider them unattractive to use (with the exception of cricket players and surfers) but they can provide excellent protection. Nano sized particles are much smaller and are transparent when applied, but are manufactured in laboratory conditions so are seen as less natural and because of their minute size, can potentially absorb into the skin.
Common conventional sunscreen ingredients such as octyl methoxycinnamate and oxybenzone (and pretty much any other listed ingredient with a very long, complicated name) are chemical-slash-organic while an ingredient such as zinc oxide (ZnO) is an inorganic ingredient and a mineral filter. Essentially, the liquid spray-on sunscreens will be chemical, while the cream sunscreens, also known as sunblock lotion, will be mineral based, or more commonly, contain a combination of chemical and mineral ingredients. Mineral sunscreens are considered less irritating to the skin and safer than chemical sunscreens.
Don’t be confused when a sunscreen is promoted as ‘organic’ or when the term is loosely thrown around; it might simply mean that it is an organic chemical based formula. If you want a certified natural or organic sunscreen, the trick is to know your ingredients. Look for products that contain only mineral filters such as zinc oxide or titanium dioxide on the label, and most importantly, have a listed SPF as well as a certification body or symbol. You will also want to look for ‘broad spectrum protection’ which means they will protect you from both UVA and UVB rays. A truly organic product will not contain chemical filters as most of these are not permitted in organic and natural certification standards.
Natural Ingredients With SPF
Now that we are a little more educated on the topic on sunscreens, let’s chat about natural SPF ingredients.
If you have been following our Oil of the Week blog series, you will have noticed we covered red raspberry seed oil, the carrot oils and sea buckthorn berry oil as a prelude to this blog.
These specialty oils are all said to have sun protection properties, along with other products such as zinc oxide powder, titanium dioxide powder and even Cape Gold helichrysum.
Some claim that coconut oil and shea butter also contain SPF properties. They may, but the SPF is so negligible at less than 1, that we do not recommend you use these to boost your sun protection factor, although they can still be added to the formula of course.
As touched on in the three blogs mentioned above, the issue with claiming that natural products such as oils have an SPF, is that there is no way to standardise the testing. Besides the fact that most brands have not tested their oils for SPF by an accredited lab so there is just no information available, natural products by their very nature vary from batch to batch. The properties of oils may differ slightly from season to season depending on climate, soil quality, and other conditions. There is no absolute standard oil. Additionally, there is no standard for what the oils will do once exposed to hot summer temperatures, air, water and sunlight. Will they oxidise or change properties, or even begin to release free radicals that will damage the skin? For all of these reasons, we will not make SPF claims on any of our oils, even if they do have sun protection properties.
But just because we can’t measure the SPF does not mean that certain oils don’t have sun protection properties or that your sunscreen won’t work, rather that one can’t simply make up a sunscreen with a verified SPF unless the product has been researched and tested in an accredited lab. So there may be an inherent risk, to a degree, when using or making natural sunscreens; whether or not it is worth it to avoid any harmful chemicals is up to us as individuals.
Here are the pro’s and con’s of DIY natural sunscreen ingredients in a nutshell:
Pros of Natural Sunscreen Ingredients
- Non toxic and chemical free.
- Known, natural ingredients.
- No coral killing compounds (please note zinc oxide may be toxic to aquatic environments in large amounts, though the small amounts in a sunscreen are unlikely to do any damage).
- Sits on the surface of your skin and doesn’t absorb deeply.
- No chemicals penetrating deeper levels of our body or possible endocrine disruption.
- If no lab testing then no way of knowing what protection you are getting; no known SPF.
- Inadequate SPF protection: a natural formula will probably yield an SPF of less than 15 (unless backed up with more UV blockers and tested in a lab) which is not enough to sufficiently protect you from UVA and UVB rays
- No formulation stability - zinc and titanium are reactive ingredients and will eventually destabilise, break down or have uneven dispersion which will render the formula less effective.
No guaranteed equal dispersion unless a homogenising machine and dispersing agent is used. Mineral filters such as zinc oxide tend to clump together microscopically; you won’t be able to see the lumps but they will exist unless blended and broken down properly with the correct machinery. Therefore you need professional equipment to blend it properly otherwise on application it will leave tiny gaps on your skin through which the sun’s rays will have no problem penetrating, resulting in sun damage. .
So what does all of this mean? Basically sunscreens are a tradeoff:
Chemical sunscreen - full of chemicals but effective.
Mineral sunscreen - zinc leaves a white residue on skin but is also effective.
Natural - can work but unknown SPF unless tested. It is chemical-free but has a good chance of not protecting you 100% so be sensible in the sun, cover up and don’t go out during midday!
If you have decided that natural, DIY sunblock is the way to go, it is easy enough to make. As we have seen, zinc oxide is a good mineral blocker that is pretty effective at protecting against the sun. Zinc is oil soluble and will blend into creams and lotions, or you can simply blend it with your chosen oils and butters. Though you won’t know what the SPF is and the zinc may not be completely homogenous throughout the formula, you should get a degree of sun protection by adding zinc powder to your cream formulation. Zinc can be used up to 25% in a formulation.
Try this basic cream recipe with added zinc oxide. Note: we are not claiming any SPF with this formula.
2-3 heaped T avocado butter
25ml red raspberry seed oil
5ml sea buckthorn berry oil
1ml carrot root extract
2-3 tsp xanthan gum
2 T aloe vera gel
½ c plus extra distilled boiled water, cooled till warm. You will need extra depending on your desired consistency.
4 drops Euxyl 940 or Geogard 221
1-1 ½ T Eco E emulsifying wax
Essential oils of choice (optional)
2-3 T zinc oxide powder
Melt the avocado butter, raspberry oil, sea buckthorn oil and emulsifying wax together in a water bath. In a separate container, blend 2 teaspoons xanthan gum, water and aloe vera gel together. It will thicken. Add the aloe mixture to the melted oils, stirring continuously. Trickle in more water, whisking vigorously. Now you can begin to blend with an emulsion/stick blender. Add in more water as required. Sprinkle a teaspoon of xanthan gum directly into the cream emulsion and blend. I find the cream improves as it cools, so keep blending until cooled completely. Test the cream every now and then on a patch of your skin. When the cream is ready, it should readily absorb into the skin, with no greasy feeling. The consistency will be thick and peaky (like whipped cream), and it should appear glossy. When your cream is done add in the geogard and blend well to disperse. Finally, add in your essential oils (if using) and stir in the zinc powder, then blend on high speed for a few minutes until the zinc is fully incorporated. Decant the cream into a jar and store in a cool place. Apply generously to skin. The zinc may clump creating small grains over time, it is nothing to worry about.
You can also add zinc oxide, some titanium dioxide plus sea buckthorn berry and red rasberry oil to the Escentia cream base if you don’t want to make your own cream. Add 2 tablespoons zinc and a heaped teaspoon of titanium a bowl and blend to a thick paste with some red raspberry and a drop or two of sea buckthorn berry oil. Then stir in 150ml of cream. Blend well with a stick/immersion blender.
To tie up natural sunscreens in a nutshell, unless tested by an accredited lab for SPF, there is no way to tell what degree of sun protection you are getting from your natural sunscreen formula. However, this doesn’t mean that natural products don’t work; in fact, zinc oxide and titanium dioxide work really well when blended correctly. So it's up to you whether to trust a DIY sunscreen or not, but regardless, it is best to be sensible in the sun, cover up and don’t go out during midday heat!