Sirloin steak, chicken, mackerel and avocados could help dieters lose weight because they trigger a reaction in the brain which makes people feel fuller, scientists have discovered.

The University of Warwick has for the first time identified the cells in the brain - called tanycytes - which detect nutrients in food and help trigger feelings of satiety.

Crucially some foods contain types of amino acids which stimulate the tanycytes more than others.

Pork shoulder, beef sirloin steak, chicken, mackerel, plums, apricots, avocados, lentils and almonds were all found to contain amino acids that activate tanycytes and therefore make people feel fuller quicker.