Twinelle began her career as a clinician in the National Health Service (NHS), specialising in acute medicine and geriatrics. During her time as a clinician, she led a significant COVID-19 initiative focused on improving clinical staff-patient communication and improving health outcomes of marginalised populations.
Twinelle's commitment to health equity is evidenced by her Master of Public Health from Imperial College London, where she conducted a systematic review on the impact of user fees on access to general practice in the European Union, currently undergoing publication.