A recent study has found strong evidence for a causal relationship between obesity and a wide range of serious conditions, including cardiovascular disease, diabetes, cancer, and neurological, musculoskeletal and respiratory afflictions. 

The study published in the journal 'The Lancet Digital Health' analysed associations between Body Mass Index (BMI) and a range of disease outcomes in 337,536 people. "In this study, we used a genetic approach to seek evidence for true health effects associated with higher body mass index, which assesses our weight against our height and is commonly used to measure obesity," said Elina Hypponen, director of the Australian Centre for Precision Health at UniSA. 

Hypponen and her team developed a multi-dimensional analysis in which genetic data were subjected to a suite of stringent examinations in order to deliver high confidence of causality. "We compared evidence to five different statistical approaches to establish how strong the evidence for causal effect actually is," she said. "Fully consistent evidence across all approaches was seen for 14 different diseases, and for 26 different diseases evidence was obtained by at least for four of the five methods used," she added. 

One key finding from the study was the extent to which it confirms existing concerns over the link between obesity and diabetes, with many of the diseases identified as related to high BMI known to be commonly associated with poorly controlled diabetes. "For example, we saw evidence for effects on peripheral nerve disorders, chronic leg and foot ulcers, and even gangrene and kidney failure, which are all known to be diabetic complications. This suggests a key aspect to reduce comorbidity risk in obesity is careful monitoring of blood sugar and effective control of diabetes and its complications," she said.