Inclusion Criteria:  Female adults aged 18-65 years. Body Mass Index equal or greater than 30 kg/m2. Weight stable at time of recruitment, defined as less than 5% variation in body weight over the preceding 3 months. Proficient in written and spoken English. Able to comply with study protocol. Willing and able to provide written informed consent.  Exclusion Criteria:  Type 1 and type 2 diabetes (in view of altered circulated gut hormone profiles and gustatory function). Smoking (in view of the fact that smoking affects salivary cortisol). Diagnosed with uncontrolled severe depression. Diagnosed with uncontrolled psychiatric disorder. Previous bariatric surgery. Acute illness or chronic conditions that may impact HPA including Cushing syndrome. Known or suspected history of HIV, Hepatitis B or C or other blood-borne diseases (in view of safety regulations regarding exposure to blood products). Currently using glucocorticoids. Pregnancy or lactation. Elevated self-perceived stress as assessed by the Perceived Stress Scale.