The lab that tested my sun cream formula, could not get higher than SPF30 using just zinc as a filter. Going higher than 30 and avoiding “nasties” at the same time, would sacrifice the product texture and could leave white residue. It turned out SPF30 based only on non-nano zinc was the optimum level. It sits well on the skin, non-greasy and not tacky. It is very safe and has no side effects. Some use it as a daytime moisturiser whatever the weather is. I personally think, sun creams should be used when the sun is shining and there is a danger of prolonged exposure. We all need some vitamin D.
Mineral filters (non-NANO zinc and titanium) proved to be the safest option, even though they can be more expensive. The list of the banned chemical filters and the countries that ban them is increasing. The penny dropped. But recently, in a local chemist, I spotted some well known brands on offer. It is my habit to read the labels as I am always curious about the incredients.
Low and behold, avobenzone (under the name of Butyl Methoxydibenzoylmethane), octocrylene and nano-particles are in vogue again, used by major mainstream brands.
The Derm Review publication warns about octocrylene: it is absorbed into the skin quite easily, thereby increasing danger of forming free radicals that may become unstable and react with other compounds forming harmful substances when used in excess quantity. This is a paradoxical concept, because the chemical is meant to decrease free radicals on the surface on the skin. But when it enters the body, it can react with other chemicals and cause changes in the deeper layers of the skin. This is why the concentration of this ingredient should be limited, as larger doses could be potentially harmful. Possible reproductive toxicity is also a possible side effect, albeit a smaller one.
I like the sunscreen I created with the help of the lab. However, my vote is for the SUN. We all need it, especially in “sunny” Manchester. You can not replace it with a vitamin D capsule. Not good enough. I was recently reading about the research in Southampton and Edinburgh on the role of sunlight in promoting cardiovascular health and, even, reducing blood pressure, let alone its vitamin D benefits. This is the link - https://www.sciencedaily.com/releases/2014/01/140117090139.htm