Rowan Jacobsen

So then, you know, I still had the sense sunlight bad, right?

So then I remember just like Googling like, so how much does sunlight like shorten your lifespan?

And like the punchline is sunlight seems to extend your lifespan.

So when I hit that, I was like, why are we not hearing this?

So that was the beginning.

It's more complicated than we thought.

So sunlight does increase your risk of skin cancer.

Depending on the type of skin cancer you're talking about, it's not necessarily like a linear relationship.

So yes, in general, too much sun increases your risk of skin cancer.

But yeah, the question is, what are the confounding factors?

How important is skin cancer compared to these other things?

If sunlight reduces your risk of other diseases, how does that weigh against the risk of skin cancer?

So it's not the type of thing that can be done in a 30-second PSA.

So ultraviolet light, which is the most energy intense part of the solar spectrum, when those photons of light hit your skin, they go inside.

We absorb all wavelengths of light to a greater or lesser degree.

And that super high energy ultraviolet light, if it hits a DNA molecule, it can mess up the DNA molecule.

And then that can lead to mutations and skin cancer.

Then it can also indirectly cause skin cancer by creating what are called reactive oxygen species, which are free radicals, basically.

So it energizes these atoms that start to steal electrons from other atoms and cause a little chain reaction, which is what a free radical is.

So ultraviolet light can increase your free radicals and it can directly damage DNA.