Summer dilemma : to go out or not

Summers are hot here . WE have no choice to go out for the most part of the day - but it is possible to bear the sun somehow early morning and half an hour before sunset .
WE may avoid totally to go out- but it may cause very quickly vitamin D deficiency .
It weakens the bone , the teeth , it makes us depressed ,irritated and for the long run it gives one bigger chance for developing any kind of cancer .
So , we must go out . But if we do so - we get wet very quickly - returning to our cooled homes we can get cold easily .Besides, we can get skin cancer when outside .So what to do ?
We must cover our body - look for the shade - drink a lot .What I have learnt about clothing : only cotton and other natural materials are bearable in the heat .Tight jeans are real self-punishment ...