As an example, I have (per month):
£500 of DD’s (includes everything on your list + TV licence)
~£400 groceries
£100 petrol
On top of a £600 mortgage.
That’s for 2 adults, plus a 5 & 1 year old.
As has been mentioned, bear in mind inflation & other increases (insurance is always going up, gas/electric is likely to go up)
Your £160 for food sounds very optimistic, but perhaps you can survive on £40 a week as a singleton.
Unless you live in a war zone you should be able to get buildings & contents insurance for a lot less than £50 per month.
Then there’s other annual costs – boiler service/cover, car tax, servicing/mot, AA/RAC membership (?), plus putting some money aside for emergencies (broken washing machine etc)
Then you’ll want some ‘going out’ spends.
Overall, £425 per month after all living expenses sounds reasonable.