Dr Jonathan Katz

Consultant Endocrinologist


Professional Membership

  • Fellow of Royal College of Physicians

  • Member of Diabetes UK

  • Member of Society of Endocrinology

Clinical Interests

  • Thyroid disorders - overactive thyroid, underactive thyroid and thyroid enlargement/goitre

  • Polycystic ovary syndrome

  • Diabetes - type 1, type 2 diabetes and insulin resistance

  • Pituitary disease (e.g. high prolactin level, pituitary tumours)

  • Testosterone deficiency; loss of libido in men and women

  • Menopause

  • Adrenal failure and adrenal tumours


Personal profile

Dr Katz studied Medicine at Cambridge University (1985-1988) and University College London (1988-1991), qualifying in 1991. He began specialist training in endocrinology in 1994, whilst working in the internationally renowned Department of Endocrinology at St Bartholomew’s Hospital.  

Dr Katz returned to University College London (UCL) for specialist registrar training from 1994-2001, working with eminent endocrinologists at UCL , The Royal Free and Whittington Hospitals. From 1996-1998, he undertook a 2-year research fellowship, culminating in an MD Thesis on “obesity and polycystic ovary syndrome”. In 1999, Dr Katz worked as a registrar in Sydney, Australia, gaining an international perspective on endocrinology. 

Dr Katz has worked as a consultant physician and endocrinologist since 2001 and was appointed as Consultant Physician and Endocrinologist at Barnet Hospital in 2005.   Dr Katz is Head of the Diabetes & Endocrinology Department at Barnet and Chase Farm NHS Trust. In 2009, Dr Katz was elected as a Fellow of the Royal College of Physicians (FRCP).  

Dr Katz has broad experience in diagnosing and treating the full range of endocrine disorders, with a special interest in thyroid disorders (overactive and underactive thyroid) , polycystic ovary syndrome and diabetes. He works closely with a highly skilled private dietician and private diabetes specialist nurse to support patients under his care.

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