Before you go nuts and change your lifestyle all together, try listing all of the things you are doing wrong.
What I mean by this, is making a list of the foods you are eating and how much of each food that you are eating. https://www.webwiki.nl/melissafarm.gr/%CE%A0%CF%81%CE%BF%CF%8A%CF%8C%CE%BD/meli-pefkou-930gr/