Chronic diseases such as diabetes, cardiovascular diseases and cancer are a major burden on the Scottish population. Obesity and inflammation have strong links to these diseases. One of the mechanisms explaining the relationship between low-grade inflammation and excess weight is "endotoxaemia". We wish to study this phenomenon, when small components coming from our gut bacteria can pass into the bloodstream, raising the body's defences. Diet can modulate endotoxaemia. In this study, we propose to use curcumin, in a capsule form, to modulate endotoxaemia. Curcumin comes from turmeric, which is widely used as a spice. In this study, we want to test the effect of consuming curcumin extract to the composition of the gut microbiota, post-meal endotoxaemia, and inflammatory markers in blood.

Inclusion Criteria:

- BMI > 25 kg/m2.

Exclusion Criteria:

• having chronic inflammatory or autoimmune disease, gastrointestinal complaints or known biliary obstruction (past and present)
• use of anti-inflammatory drugs 2 weeks before the start of the study
• use of antibiotics during the 12 weeks preceding the trial
• pregnancy
• lactation