Martin Knight eating his breakfast
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Can eating less help you live longer?

11 February 2013 Last updated at 01:02 GMT

Experiments on mice have shown that eating significantly less food can extend their life spans, so long as the food is highly nutritious.

Some people choose to follow a similar path and restrict the number of calories they consume, in the hope of a longer life.

Peter Bowes met one adherent to this way of life to find out exactly what he eats and whether it is likely to work.