I want to talk about sunscreen today. Even though we have discussed this in previous blog posts on this site, I feel strongly enough about it that it pays to review.
Note 1: The sun emits, or sends out, all kinds of radiation. This is not the kind of radiation that will kill you instantly, because it is lower in energy than radiation that kills, but it is high enough in energy that it can cause damage. What kind of damage does sun cause? It can make the molecules in your cells break apart, and break apart in a way that creates free radicals, or species that have single unpaired electrons. Such free radicals are highly reactive, and can cause lots of unchecked reactivity in your cells with species that you do not want, including with your DNA and RNA.
Note 2: Free radicals that react with your DNA to cause unchecked outcomes can cause mutations, or changes in the DNA that stop it from being able to produce the proteins that it is supposed to be coding for. Such mutations can harm the cell itself, but if they are replicated when the cell divides, can cause harm in future cells as well.
Note 3: What kind of harm are we talking about? In some cases, such harm to the DNA can cause cancer, which is a blanket term that refers to many kinds of diseases of unchecked growth in the cells. You do not want this to happen.
Note 4: What does sunscreen do? It blocks at least part of the radiation from the sun, either through physically blocking the rays from getting into your cells (with extremely small blockers like nanoparticles) or through chemical blockers that absorb the radiation and use it to cause chemical reactions, but also prevent the radiation from reaching your cells. Both types of sunscreen work if applied effectively (frequently, in large enough quantities to cover exposed skin), although there is some evidence that physical blockers can lead to less skin irritation and potentially more protection.
What to find out more about sunscreen? Check out some of the links below!