Myth No. 8 - DIY Sunscreens
We talked about why sunscreen is a daily skincare essential and how mineral sunscreens are preferred over chemical sunscreens in Myth No. 7. So some people will ask, zinc oxide (the mineral that makes sunscreen white and pasty) is easy enough to find, and some carrier oils are said to have some Sun Protection Factor ("SPF"), so why not take a stab at making your own sunscreen?
First off, let's take a step back to look in more detail at how mineral sunscreen works. There are two types of zinc oxide and titanium dioxide which may be found in mineral sunscreens, nano-sized and non-nano-sized. Nano-sized mineral particles are designed to battle the white cast that is left when these minerals are spread across the skin. They are small enough (under 100nm) that they only reflect UV light but not visible light, thus will appear transparent to the naked eye. However, due to their small size, they may have the ability to penetrate our skin and accumulate within our bodies and research has shown this may happen to people with poor skin conditions (Cross et al., 2007).
Non-nano-sized may be the safer option in this regard; however, mineral UV filters are prone to clumping together to form microscopic lumps that cannot be seen by the naked eye. The danger here is that the minerals won’t be applied evenly onto the skin, leaving gaps that will be exposed, resulting in sun damage. In order to ensure proper mixing of these minerals, use of professional equipment and addition of special dispersing agents are required in the formulation. Hence, it is not a product amateur or low-budget formulators should venture into.
Aside from mineral sunscreens, there are also those who label a natural skincare product as having SPF protection by adding carrier oils that are reputed to offer some level of SPF protection. Here are a few examples with their respective reputed SPF levels:
- Coconut oil: 4-6
- Red raspberry seed oil: 28-40
- Carrot seed oil: 38-40
Well! I say “reputed” SPF levels because scientific research conducted to date has not been able to measure with certainty the in vivo SPF levels - which are based on the reaction of skin under exposure to UV light. Existing research has either been measuring the in vitro SPF levels (without application to human skin) or the tested carrier oils have been measured while mixed with other ingredients.
Here’s my personal rule of thumb - if the sunscreen isn’t offered by a big-name commercial brand that can be found at big-name supermarkets, I won’t go near it with a ten-foot pole.
For babies under 6 months old, best altogether avoid the sun by staying indoors (especially between 11am - 3pm when the UV rays are the strongest) or wear proper sun protection attire such as wide-brimmed sun hats and loose-fitted clothing providing full-body coverage. Because their skin is so delicate, sunscreen is not recommended.
For more information, refer to the Health Canada website here.