Diabetes is an increasingly common condition which affects millions of people in the United Kingdom. Patients with type 2 diabetes are at increased risk to develop severe heart disease and vascular complications and these can result in death. A cornerstone of the treatment is lifestyle and diet.

The number of travellers is increasing quickly and there are more people than ever travelling by airplane. During a commercial flight the pressure of the air is lower than the pressure on the surface and that results in lower concentration of oxygen in the air we are breathing while flying. Also the humidity is very low inside an aircraft.

The aims of this study are to show if we can use a simulated flight as a method to look at how the endothelial cells react and to see if this is different between patients with type 2 diabetes mellitus and healthy volunteers.

A sub-study is also incorporated to look at different dietary interventions in type 2 diabetes.

Inclusion Criteria:

Diabetes group:

• Diagnosis of type 2 diabetes
• Patients on stable medication (for their diabetes metformin being the only treatment if any), for 3 months prior to entry into the study
• Age between 45-75 years at the start of the study; women need to be postmenopausal and not undergoing hormone replacement therapy (HRT)

Healthy volunteers group:

• No current disease or medication which would have effect on the safety of the subjects or interfere with the study results
• Age between 45-75 years at the start of the study; women need to be postmenopausal and not undergoing HRT

Exclusion Criteria:

• For both groups:

  • Patients with concurrent illness or any medication in the last 3 months that would interfere with the study based on the investigator's judgement
  • Acute coronary syndrome in the last 3 months or any major clinical event in the previous 3 months that would effect the study based on the investigator's judgement
  • Patients not wishing to allow disclosure to their general practitioner (GP)s.
  • HbA1c >9%
  • Smokers
  • Pre-menopausal women or post-menopausal women on HRT
  • Claustrophobia, panic attacks in the anamnesis
  • Subjects must not have been subjected to a commercial flight within 4 weeks of the study