Averaging out daily food cost for 1 person at 180 thb per day, which includes 3 meals with drinks, at an average of 60 thb per meal. Total 5,580 thb per month or US $175.00 per person.
This is eating locally from local mom & pop shops, to buying pre-cooked food in the local markets.
I feel like I am getting plenty of food each day at this price.
There is also an enormous variety so I do not feel I am missing anything.
If you can live in rural Isaan and eat like a local, your food budget for the month will be quite low or you can go nuts and spend even more by buying things from 7 eleven.
180 thb per day is probably a lot more than most locals are spending per day.