GendAge Weight Loss Study

  • Research type

    Research Study

  • Full title

    GendAge Weight Loss Study: Sex hormones as regulators of the age- and sex-dependent benefits of caloric restriction

  • IRAS ID

    354348

  • Contact name

    Alex Johnstone

  • Contact email

    alex.johnstone@abdn.ac.uk

  • Sponsor organisation

    University of Aberdeen

  • Clinicaltrials.gov Identifier

    NA, NA

  • Duration of Study in the UK

    2 years, 11 months, 31 days

  • Research summary

    Obesity increases the risk of diseases such as type 2 diabetes, cardiovascular disease, and some cancers. With nearly two-thirds of the UK population living with overweight or obesity, there is a desperate need to provide evidence-based public health advice for healthy weight. Current weight management advice is around lifestyle modification and does not account for gender or age. This is a surprising oversight as it is well established that health outcomes differ substantially between men and women. Our recent research in mice and humans has revealed that females resist weight loss and fat loss in response to dieting. As females age, the sex hormone, oestrogen, decreases, linked to menopause at around 50 years. One possibility is that oestrogen directly influences these age-sex differences in the dieting response. We propose to conduct a diet study in 75 men and women, with all food provided, and monitor changes in energy expenditure and body composition using gold-standard techniques. We will collect blood samples and fat tissue samples, from under the skin in the abdomen, to examine if mechanisms associated with sex hormones can explain these sex and age differences in calorie restriction. Considering the potential role of oestrogen, women who replace hormones using hormone replacement therapy (HRT) may have a reduced response to calorie deficit because they have a similar hormone profile to younger women. To test this hypothesis, we will recruit a small cohort of older females who take HRT, to participate in the same dieting study, to assess the interaction of sex hormones and age. Together, these studies support translational understanding of diet and women’s health to combat obesity and achieve healthy ageing.

  • REC name

    South Central - Berkshire B Research Ethics Committee

  • REC reference

    25/SC/0193

  • Date of REC Opinion

    25 Jun 2025

  • REC opinion

    Further Information Favourable Opinion