Edzard Ernst (born 30 January 1948) is a retired British-German academic physician and researcher specializing in the study of complementary and alternative medicine.

He was born and trained in Germany, where he began his medical career at a homeopathic hospital in Munich,[2] and since 1999 has been a British citizen.

Ernst is the founder of two medical journals: Focus on Alternative and Complementary Therapies (of which he was editor-in-chief until it was discontinued in 2016) and Perfusion.

[8] He learned homeopathy, acupuncture and other modalities[9] whilst at a homeopathic hospital in Munich, when he began his medical career.

[5] In a 2008 publication in the British Journal of General Practice, he listed treatments that "demonstrably generate more good than harm", identifying only acupuncture for nausea and osteoarthritis; aromatherapy as a palliative treatment for cancer; hypnosis for labour pain; massage, music therapy, relaxation therapy for anxiety and insomnia; and some plant extracts such as St John's wort for depression; hawthorn for congestive heart failure; and guar gum for diabetes.

[14] In 2005, a report by the economist Christopher Smallwood, personally commissioned by Prince Charles, claimed that complementary and alternative medicine was cost-effective and should be available in the National Health Service (NHS).

[15] Ernst was, in turn, criticised by The Lancet editor Richard Horton for disclosing contents of the report while it was still in draft form.

In a 29 August 2005 letter to The Times Horton wrote: "Professor Ernst seems to have broken every professional code of scientific behaviour by disclosing correspondence referring to a document that is in the process of being reviewed and revised prior to publication.

"[16] Prince Charles' private secretary, Sir Michael Peat, also filed a complaint regarding breached confidentiality with Exeter University.

Although he was "cleared of wrongdoing",[17] Ernst has said that circumstances surrounding the ensuing university investigation led to his retirement.

[15] In the 1 January 2006 edition of the British Journal of General Practice, Ernst gave a detailed criticism of the report.

[20] In a review of Trick or Treatment in the New England Journal of Medicine, Donald Marcus described Ernst as "one of the best qualified people to summarize the evidence on this topic.

[22] In a 2008 interview with Media Life Magazine, when he and Simon Singh were asked this question—"What do you think the future is for alternative medicine?

[24]In 2018, Ernst and co-author Kevin Smith, a medical ethicist, published the book More Harm Than Good?

In a review of the book for Skeptical Inquirer, Harriet Hall called Ernst the "world's foremost expert on the claims and the evidence (or lack thereof) for Complementary and Alternative Medicine (CAM).

"[25] Hall said that Ernst and Smith direct their attention to the ethicists and the scientific community for this book with the goal "to inform, not to entertain.

[25][26] Dougal Jeffries, writing for the British Journal of General Practice, said the book was "replete with both theoretical and real-life examples and is thoroughly referenced, but is a rather turgid read.

It clearly demonstrates the extraordinary capacity of intelligent beings, including both practitioners and patients, to hold to irrational beliefs in the face of contrary evidence, but the authors show little sympathy for this very human tendency.

"[27] Ernst was accused by Prince Charles' private secretary of having breached a confidentiality agreement regarding the 2005 Smallwood report.

When my department had been destroyed in the process, I retired voluntarily and was subsequently re-employed for half a year to help find a successor.