- ? - 1986 - Wellcome Research Fellow at the Wellcome Unit for the History of Medicine at the University of Oxford.
- 1986 to 1993 - Senior Research Officer for the Coronary Prevention Group (Oxford University)
- ? - ? - Vice-Chair of Sustain: the alliance for better food and farming 
- ? - ? - Trustee of the National Heart Forum.
- ? - ? - Chair of the Nutrition Expert Group of the European Heart Network 
- ? - ? - member of the Public Health Interventions Advisory Committee of NICE (the National Institute for Health and Clinical Excellence).
- ? - ? - Editor of the journal Ministers-at-Work
- 1997(?) - current - Director of British Heart Foundation Health Promotion Research Group
- 2007 - current - Ordained priest in the Church of England
- 2008 - current - Assistant Curate at St Matthew’s Church, Oxford.
Mike Rayner has publicly called for increases of, or special taxes on, food deemed to be 'unhealthy' in order to dissuade people from buying as much and magically reducing obesity.
In May of 2012, he called for up to a 20% increase in the price of 'unhealthy food,' or up to 12p on a can of soft drink (At the time, a 24 pack of Coke could be obtained for £9.99 which is just under 42p a can, so an increase of 28.5%)