Relationships Between GLP-2 and Markers of Bone Turnover Following Feeding

Inclusion Criteria: * Age 25-40 * Caucasian * Premenopausal * Able and willing to consent * BMI either 18.5-24.9 kg/m2 or ≥30 kg/m2 * Completion 'The Effects of Obesity on Bone Structure and Strength' study REC ref 10/H1308/61 * Consented to be approached for future research studies Exclusion Criteria: * Fracture less than twelve months prior to recruitment * History of any long term immobilization (duration greater than three months) * Current pregnancy or trying to conceive Pregnancy or breast feeding less than one year prior to recruitment * Diabetes mellitus * History of or current conditions known to affect bone metabolism, which may include: * Diagnosed skeletal disease or osteoarthritis * Chronic renal disease * Acute or chronic hepatic disease * Hyperparathyroidism or Hyperthyroidism * Malabsorption syndromes * Diagnosed endocrine disorders * Diagnosed diabetes mellitus * Clinically significant hypocalcemia or hypercalcemia * Diagnosed restrictive eating disorder * Current or clinically significant previous use of medications or treatment known to affect bone metabolism, for example: * Depot medroxyprogesterone or the combined oral contraceptive pill * Glucocorticoid therapy * Anti-convulsant therapy * Bone treatments (e.g. Bisphosphonates) * Alcohol intake of greater than 21 units per week * Athlete, defined as an individual participating in competitive sport at amateur or professional level * Monogenic and obesity syndromes * History of cancer within the past 5 years excluding skin cancer non melanomas