Which neighbourhoods in and around London are relatively poor, but overwhelmingly white and native British?

Can you think of any areas in or around London that are down and out, but still predominantly white and populated mainly by indigenous English people? Or is London inhabited with only one of two categories of people, wealthy white Brits and other nationalities or impoverished people of colour. Thus representing the two extremes of modern British society, with not much room for anything in the middle. If you can name one area in London that is poor and overwhelmingly white & British, please tell us.