Obesity is known to have effects on cellular metabolism, which is reflected in a person’s circulating metabolome. Metabolomics, defined as the measurement and study of circulating small molecules that are the substrates and products of cellular metabolism, is increasingly used by epidemiologists to provide a functional read-out of bulk cellular activity and a proxy to individual current health. This approach also provides insight into biological pathways linking exposures and disease.

Measuring the metabolome of people with measured body mass index (BMI) allows us to look for ways in which BMI affects the metabolome. Metabolites found to be associated with BMI can then be further investigated and linked to cellular pathways – knowledge which will help us to understand the pathology of obesity. We have already begun to look at how bariatric surgery (within the By-Band-Sleeve trial (BBS), https://bristoltrialscentre.blogs.bristol.ac.uk/details-of-studies/by-ba...) and non-surgical weight loss interventions (within the DiRECT trial, https://www.directclinicaltrial.org.uk/) affect the metabolome. We want to use samples collected during routine ALSPAC clinics to characterize the metabolome of a healthy cohort. By analysing ALSPAC samples at the same time as samples from BBS (i.e., within the same experiment) we will be able to analyse the data together (without concerns of batch structure) and compare the metabolome of healthy ALSPAC participants to patients before and after bariatric surgery. When brought together with other work from our group, this study will enable us to unpick the metabolomic effects that are associated with BMI and their relevance to disease.