Postma graduated with a degree in medicine in 1978. She specialised in pulmonology. In 1984 she obtained her PhD-degree with a thesis entitled Reversibility of chronic airflow obstruction.[2] After graduation, she worked for the Longfonds (then called Astmafonds), a Dutch health organisation. On behalf of this organisation, she became endowed professor at the University of Groningen. In 1998 she got appointed as full professor Pathophysiology of the respiration at this university. On 1 April 2016 Postma retired.
Postma's research focusses on asthma and COPD. She co-authored over 600 peer-reviewed papers in journals such as New England Journal of Medicine and the Lancet. Because of her research, steroids are nowadays used to mitigate the symptoms of asthma. Her research has been beneficial to millions of people suffering from respiratory illnesses.[3]
One of the results of her research is that asthma and COPD can be distinguished from each other. Postma and co-workers found out that genetic variants occurring in people suffering from allergies also occur in people suffering from asthma and those with a higher risk of myocardial infarctions. These links between these conditions have led to new insights in how to treat those conditions.