As a Greek, is public knowledge (and constantly warned about) that you should avoid the sun between 11-15:00 during summer (for UK the hours extend to 16:00). Is the worst period for high UV radiation and no sun cream can help you. While the body is working overtime to keep your cool. Which if it fails to do so, can lead to sudden death or illness and high fever for days.
Also no more than 15-20 minutes per day.
The hours under direct sunlight on the garden,or on their holidays, many Britons do, leads to skin cancer. And the different lighter skin pigment the majority has here is even worse.
And I am not talking about the dangerous type cancer, but even brown dimples on the skin is cancer. Which personally I find them disgusting looking like dirt.
I went to the super market yesterday noon, and saw almost everyone with a roasted brown colour. Which is wrong on health grounds.
If you go to Greece in September you won't find anyone that dark, even when whole summer is spent at the beach daily, like I used to do.
Hell hadn't been that dark even in the army on both summers of 1996 & 1997. And all the day we were out and about, which included daily 2 hours of running and physical exercise while top less. And if noon hours we were out under the sun, sleeves had to be pulled down and all buttons closed to the neck to avoid the metallic tag burning your chest skin. Which believe me is painful.