I take a supplement called Astaxanthin. This is primarily for eye health however it has a natural sun screen effect. It is what gives fish UV protection.
I can say from my own experience that this definitely works as a sun screen. I went to Disney land in August '17 and was there for 3 days. I did not burn one bit (which I would normally do) and I didn't wear sunglasses one of the days and noticed that I had no issues with glare or the need to wear sunglasses (this is also not the norm for me).
From what I've read, it takes a few weeks for the product to have these benefits. I take it every day.
https://www.nutrex-hawaii.com/blogs/learn/astaxanthin-explained