None listed
Conditions
Brief summary
Weight cycling (yo-yo dieting) is an ongoing battle for many obese individuals and is commonly believed to impair energy metabolism and promote future weight gain. However, scientific evidence for this idea remains scarce and mechanisms of how this occurs has not been examined in humans. The aim of this study is to investigate whether weight-cyclers have impaired energy metabolism, greater fat deposition and greater circulating and fat tissue inflammation compared to non-cyclers. 100 overweight/obese women undergoing bariatric surgery will be recruited into this study. 60 women (30/group) will be classified as weight-cyclers or non-cyclers using a validated questionnaire. Blood and fat tissue samples will be collected at the time of surgery and markers of inflammation measured in the laboratory. Clinic visits will be performed at baseline prior to surgery and at 6, 12 and 24 months after surgery. Measurements include anthropometry, body composition, resting metabolic rate and circulating markers of cardiometabolic disease (glucose, insulin, HbA1c, lipids, inflammation). Using a rigorous scientific approach and comprehensive clinical phenotyping we will address whether individuals who weight cycle have reduced energy expenditure and greater fat deposition. These results will assist in tailoring personalised weight loss treatment strategies for the over 70% of Australians affected by overweight and obesity.
Interventions
This is a longitudinal observational study to examine clinical phenotypes and adipose tissue characteristics of weight-cyclers vs non-cyclers. Pre-menopausal obese women undergoing bariatric surgery will be recruited and followed up for 2 years. Prior to surgery, patients will fill in a validated questionnaire to categorise them into weight cyclers or non-weight cyclers and body composition (DXA) and resting metabolic rate (hand-held respirometer) will be measured. At the time of surgery, a fast
This is a longitudinal observational study to examine clinical phenotypes and adipose tissue characteristics of weight-cyclers vs non-cyclers. Pre-menopausal obese women undergoing bariatric surgery will be recruited and followed up for 2 years. Prior to surgery, patients will fill in a validated questionnaire to categorise them into weight cyclers or non-weight cyclers and body composition (DXA) and resting metabolic rate (hand-held respirometer) will be measured. At the time of surgery, a fasting blood sample and subcutaneous and visceral adipose tissue biopsies will be obtained. Participants will return to the clinic at 6, 12 and 24 months to measure anthropometry, resting metabolic rate and body composition.
Sponsors
A/Prof Michael Talbot
Eligibility
Sex/Gender
All
Age
20 Years to 45 Years
Healthy volunteers
No
Inclusion criteria
Premenopausal women aged 20-45y seeking elective surgical treatment for obesity and with a body mass index >30kg/m2
Exclusion criteria
-Diabetes diagnosed more than 5 years ago -Previous bariatric surgery -Any metal implants/devices -Women on a commercial weight management program at preoperative appointment -Women with active gastrointestinal disease (eg. IBD) -Women who are pregnant or unwilling to avoid pregnancy for 2 years post-operatively -Women taking medication that may affect energy expenditure (eg. beta blockers, antipsychotic medication)
Outcome results
None listed