This is a state in which people cannot afford
to have sufficient good food
. This is not just absolute food poverty
, which is the state of not being able to afford enough daily calories to maintain one's health, but also the state of being able to afford enough daily calories, but not to consistently form a balanced diet.
Symptoms of this are eating various processed foods and junk food, as they have much more energy per unit cost than fresh foods. When feeding children comes into the equation, parents often have to take account of how fussy children are, and so need to buy socially acceptable (in this context, socially mediocre) foods. Children are like that: stupid.
While there is food poverty in the UK, it is incredibly difficult to get any information about it, especially recent information. I wish I had more to tell you.