Natal van Riel's career is a prime example of the increasingly blurred boundaries between the traditional scientific disciplines. After having studied Electrical Engineering he specialised in systems biology, where his knowledge of control systems and (electrical) networks proved highly useful. Van Riel conducts research on the development and application of computer models for metabolism and metabolic networks. The causes and effects of metabolic diseases are rarely easy to trace. This is partly due to the complexity of the human metabolism, which comprises countless sub-processes that affect each other in myriad ways. Computer models – when combined with various 'omics' technologies – are increasingly effective at correlating the outcomes of blood or urine tests with diseases such as diabetes. As part of his appointment at the AMC-UvA, Van Riel will develop his computer models further and test them in clinical situations. Amongst other aspects, he will be focusing on bariatric surgery (gastrectomies and re-routing of the small intestine) in patients suffering from metabolic syndrome (obesity-related metabolism problems, resulting in conditions such as diabetes and cardiovascular disease). Van Riel will also be contributing to the development of an Amsterdam Diabetes Centre.

Van Riel has served in various positions at Eindhoven University of Technology (TUE) since 2000, and worked as associate professor of Systems Biology and Metabolic Diseases at the Biomedical Engineering department since 2014. He also serves as a senior researcher at the TUE's Institute for Complex Molecular Systems. In 2014, Van Riel served as a guest researcher at the department of Bioengineering of the University of California, San Diego (US).