Metabolic syndrome is the medical term for a combination of diabetes, high blood pressure and obesity.
It puts you at greater risk of getting coronary heart disease, stroke and other conditions that affect the blood vessels.
On their own, diabetes, high blood pressure and obesity can damage your blood vessels, but having all three together is particularly dangerous.
They're very common conditions that are all linked, which explains why metabolic syndrome affects an estimated one in four adults in the UK.