These are some doctors I have personally visited and other resources I have come across. They might help you on your journey.

LONDON/ EUROPE

• Dr. Shideh Pouria has worked in numerous clinical and academic posts within the NHS. She has extensive experience in general and specialist medicine as well as in medical research in the field of mucosal immunology. She previously held posts at Guy’s Hospital in Renal Medicine and was Medical Director at the Burghwood Clinic for Allergy, Environmental and Nutritional Medicine. Her approach to medical problems is based on the concept of cause and effect as well as seeking out the effects of environmental and nutritional factors on the health of the individual. She is dedicated to creating a system of individualized comprehensive health care for her patients based on sound scientific and clinical research and evidence.

Dr. Shideh Pouria
The Elixir Clinic
75 Wimpole Street
London W1G 9RS
Tel: 020 7486-9748
Email: secretary@drpouria.com

• Dr. Bernard Willis, a GP specialized in Hashimoto’s, has unfortunately retired, but recommends these colleagues in London.

Dr. John Moran
The Holistic Medical Clinic,
69 Wimpole Street,
London W1G 8AS,
Tel: 020 7631 1111
Email info@holisticmedical.co.uk.

Dr. Wendy Denning MBBS, MRCGP, DRCOG, GCFP, DCMac
The Health Doctors
4 Harley Street
London
W1G 9PB
Tel: 0207 224 2423 
Email tosh.drdenning@gmail.com

• Practitioners who are members of Clinicial Education, a non-for-profit that represents the Institute for Functional Medicine in the UK and EU, by sponsoring and organizing the IFM educational events to cater for practitioners and clinicians, are listed in the link below. I would advise to search for a GP, as other disciplines are also included.
  
  See list…

NEW YORK

• Dr. Loren Marks in New York is an incredible functional medicine doctor. His clinical knowledge and understating of biology speaks to evidence-based medicine.

Dr. Loren Marks
200 West 57th Street
Suite 1010
New York, NY 10019
Tel: 212-333-7300
https://www.docmarks.com

• I came across Tapp Frank in The Hamptons this summer. Her practice started being mostly focused on lyme’s disease, but she treats autoimmune conditions, cancer and other illnesses. A gem of a find!

StandWellness
50 Station Road
Building 3 Unit 1
Watermill, NY 11976
Tel: 631-500-9021
https://www.standwellness.com