Hydroxytyrosol extracted from olives and/or from the solid residues of olives after the extraction of olive oil, by acid hydrolysis and purification on resin columns eluted with water contains hydroxytyrosol and tyrosol, is free from sugars, has a residual content of Benzo[a]pyrene that is less than 2 microg/Kg (weight BaP/weight of extract as dry matter), containing a weight ratio of hydroxytyrosol to hydroxymethylfurfural of between 45:1 and 10000:1, and the content of hydroxytyrosol in the extract is at least 0.5% (w/w) with purity of at least 40% (by HPLC 280 nm).