Prior to Innocent, which he joined in January 2007, Helm worked at Cereal Partners as marketing manager on its adult brands, rising to head of Nestlé brands, cereals and cereal bars. He has also worked at Unilever, Kraft Jacobs Suchard and St Ivel Foods.
Innocent's UK managing director, Jamie Mitchell, will assume responsibility for the firm's marketing team. Charlotte Rawlins, head of communications, will continue to head the brand's internal creative agency as well as its below-the-line and public relations teams.
Richard Reed, co-founder of Innocent, said: 'We are sad to see Gareth go. He's invested an enormous amount of energy and passion into his role. As three guys who took the plunge ourselves, we always celebrate entrepreneurialism. So we wish him the best of luck setting up his consultancy.'