Eating a Mediterranean diet may help prevent depression, research suggests.

But an expert in metabolic medicine says more rigorous, targeted trials are needed to confirm evidence of the potential link.

The findings, in Molecular Psychiatry, come from a review of 41 studies published within the last eight years.

A plant-based diet of fruit, veg, grains, fish, nuts and olive oil - but not too much meat or dairy - appeared to have benefits in terms of mood.

Experts say trials are now needed to test the theory and to learn whether depression can be treated with diet.