There is a largely unsubstantiated thought in the literature that dietary unsaturated enter oxidation pathways preferentially compared to saturated fatty acids. This study is undertaking a direct comparison of the oxidation of dietary saturated and unsaturated fatty acids.

Provided subjects meet the inclusion criteria, then at least one week after the screening visit volunteers will then undertake the first two 'study days'. There will be two study days on separate occasions that will be up to 3 weeks apart. Each study day will be approximately 7 hours in duration. On each study day participants will be given a standardised 'test' meal that contains specially labelled fat molecules (stable-isotope tracer) and then repeated breath and blood samples will be taken over the course of the next 6 hours. The test meal consumed on each 'study day' will be identical in composition with only the specially labelled fat molecules being different (either unsaturated or saturated fat) and these will be given in a random order.

Inclusion Criteria:

Participant is willing and able to give informed consent for participation in the study.

Male or Female, aged >18 and <65 years BMI >19 <35kg/m2 No medical condition or relevant drug therapy known to affect liver metabolism

Exclusion Criteria:

• • Age <18 or >65 years

  • Body mass index <19 or >35kg/m2
  • A blood haemoglobin <120mg/dL
  • Any metabolic condition or relevant drug therapy
  • Smoking
  • History of alcoholism or a greater than recommended alcohol intake
  • Pregnant or nursing mothers
  • Women prescribed hormone replacement therapy (HRT) or who have used this within the last 12 months
  • History of severe claustrophobia
  • Presence of metallic implants, pacemaker
  • Haemorrhagic disorders
  • Anticoagulant treatment