Healthy food IS cheap in the UK.
I feed me & 16yo ds for about £55 p. week. That always includes a good range of fruit, veg, meat and dairy. I eat 30+ different fruit & veg every week to boost my immune system after being treated for cancer a few years ago and always cook from scratch.
Last week we ate potatoes, carrots, onions, broccoli, radishes, cucumbers, tomatoes, beetroot, lettuce, spring onions, garlic, spinach, rice, oats, celery, mushrooms, peppers, fennel, courgettes, lentils, frozen peas, sweetcorn & broad beans,.
Plums, apples, kiwis, mango, satsumas, strawberries, rhubarb.
I also make all our bread from wholemeal flour bought direct from a mill.
It really isn't difficult. Food in the UK is very good value compared to some other countries. It doesn't need subsidising, we just need to teach some people how to cook.