Revealed: the secret to a fuller, slimmer you

UK and Australian scientists believe they have identified how the hunger fighting hormone, peptide YY, (PYY) can be increased by eating a protein-rich diet, including meat and fish.

Although scientists have always known that high-protein meals help make people feel fuller and reduce appetite, the mechanism for this has always been unclear.

Now, they believe they have found the answer. Published in

Cell Metabolism, the researchers outlined how PYY can reduce food intake by a third in both normal weight and obese people when administered by injection.

"We've now found that increasing the protein content of the diet augments the body's own PYY, helping to reduce hunger and aid weight loss," said lead researcher Rachel Batterham, of University College London, a medical

research council clinician scientist.

Studies were carried out in normal weight and obese people and found that enhanced protein meals stimulated greater release of PYY than either high-fat or high-carbohydrate meals and resulted in less hunger.

The findings were supported by tests using mice. Genetically modified mice, unable to produce PYY, ate more and became noticeably obese. When they were treated with PYY, they lost weight.

"One potential weight loss strategy is therefore to increase the satiating power of the diet and promote weight loss through the addition of dietary protein - harnessing our own satiety system," said Dr Batterham.

However, she said that large, long-term clinical trials were necessary before any particular diet could be recommended.