About Me

Are you suffering from diabetes or thyroid disorder? If so, learn what Marie Angelica A. Diaz, MD, at Avera Medical Group Endocrinology & Diabetes in Sioux Falls, SD can do to help you live a more healthy and active life. Inspired by family and a wonderful teacher, Dr. Diaz pursued her field of study to be able to help those with hormone-related health needs.

Expert Care for Your Endocrine System

Diabetes can be a challenging condition to live with every day, especially with insulin therapy. Dr. Diaz understands that specialized care for your endocrine system is what can make the difference in a healthy, fulfilling life. Treating adults, she is a board-certified doctor who has years of experience with conditions involving the body’s interconnected gland system.

Her specialties include:

  • Diabetes management and prevention
  • Metabolism and weight management
  • Thyroid disorders
  • Lipid disorders
  • Obesity
  • Adrenal disorders
  • Pituitary disorders
  • Calcium and bone disorders
  • Male and female reproduction

“Strive to maintain a healthy lifestyle,” says Dr. Diaz—whether eating healthy, exercising or keeping your mind healthy. She loves getting to know her patients and building relationships.

Dr. Diaz’s favorite part of medicine is caring for people. “I enjoyed treating patients,” she says of her studies in medical school. She has participated in research, is published in case reports—and has presented on endocrine topics at universities and national meetings.

Active Lifestyle

In her free time, Dr. Diaz loves going for walks with her Siberian husky. She speaks Filipino and is originally from Manila.

Experience

Education

University of Santo Tomas, Manila, Philippines, Medical School

Residency

Monmouth Medical Center, Long Branch, NY, Internal Medicine

Fellowship

University of Florida College of Medicine, Jacksonville, Endocrinology, Diabetes & Metabolism

Professional Memberships

  • American Association of Clinical Endocrinologists
  • Endocrine Society
  • American College of Physicians

Certifications

  • American Board of Internal Medicine - Endocrinology, Diabetes, and Metabolism
  • BLS
  • ACLS
  • NIHSS

Reviews

We value patient feedback and are committed to providing you with information, so you can make informed decisions about your health care, physicians and other providers in your care journey. Patient ratings and comments are gathered from the post-visit experience survey. Learn more.

January 29, 2026
Good experience
January 28, 2026
We had a very productive discussion about the minor side effects of my medication. She helped me make the best choice.
January 24, 2026
Always easy to speak with Dr Landicho Diaz
January 23, 2026
Dr. Diaz is the best!
January 21, 2026
Every person we came in contact with from check in to leaving the clinic following my appointment and procedure was extremely friendly and helpful.
January 13, 2026
Excellent Service.
December 20, 2025
She is amazing!
December 15, 2025
I've always a great relationship with Dr. Diaz when it's come to my care and options available or potential changes to continue to manage my health and medical concerns.She's been a very good Physician and provides excellent compassion and care.
December 05, 2025
Good appointment
November 27, 2025
I really like Dr Diaz she's very good she is very through and explains everything very good and I can understand her
November 20, 2025
The nurse I had she was so friendly and has a bubbly personality. Dr. Diaz and her nurse showed compassion, care, and all around amazing.
November 18, 2025
My doctor and nurses are great
November 17, 2025
Great experience
November 12, 2025
I was seeking information and that's what I received.
November 09, 2025
Doctor Diaz is amazing
November 06, 2025
Very good rxperience
October 31, 2025
The nurse that took care of me was very gd
October 23, 2025
She was so good at explaining and was listening to my concerns. Very impressed.
October 22, 2025
I have shared information about my doctor with others who have thyroid symptoms the nurse was the greatest nurse we have ever encountered. Love that wittiest personality she has.
October 19, 2025
All contacts were very knowledgeable and very efficient with getting follow-up appts scheduled and very good with all- inclusive details about what to expect in future
October 15, 2025
Very friendly Doctor and staff and Dr. Diaz took her time showing me ultrasound results and explaining what it meant!
October 15, 2025
Dr. Diaz was very thorough and obviously very knowledgeable about my situation. She explained what was going on and how the visit would progress. Kept me informed during the procedure and summarized well and let me know what to expect along the treatment journey. Very positive experience!
October 15, 2025
Dr very knowledgeable.
October 15, 2025
Dr. Diaz and her nurse are always so happy bubbly joking around. They make you feel comfortable .very knowledgeable. Always makes you feel good after you've been there just cause they're so upbeat
October 09, 2025
Excellent care from nurses and Doctor.
October 08, 2025
Very knowledgeable courteous and informative
October 03, 2025
Dr Diaz was so kind, and patient and even though we had to wait for ultrasound results. We talked about how I was feeling and that she would contact me if results did not arrive before I left.
September 28, 2025
This was my first visit with Dr. Diaz and I was very impressed with her! She listened, explained things, talked about my care plan and did not rush in and out of the room. Love her!
September 22, 2025
My visit went very well.
September 21, 2025
Very nice and polite
September 15, 2025
Dr Diaz is very thorough and is very kind and friendly..
September 11, 2025
Dr Diaz and her staff are excellent.
September 07, 2025
Awesome !!!!
September 06, 2025
Dr Diaz is outstanding. We immediately connected.
August 30, 2025
My husband ended up in the ER the day of my appointment. I called to see if I could squeeze in a bit early so I could be there for my husband. The entire staff went above and beyond to get me in and on my way. Everyone was kind, caring and professional.
August 23, 2025
Dr.Diaz is geat!
August 11, 2025
Good
August 06, 2025
Dr. Diaz is a very Caring and knowledgeable.
July 20, 2025
I have always enjoyed the endocrinologist that have taken care of me. When my past doctor moved, Dr. Diaz was a wonderful doctor and treated as well as I was previously.
July 11, 2025
Doc was great
July 04, 2025
Awesome
July 01, 2025
Dr Diaz is very nice, always concerned about how I'm doing. She's very thorough regarding my health care.
June 29, 2025
Professional and knowledgeable
June 29, 2025
Dr Diaz is an amazing doctor. She explained everything in detail and informed me of my treatment options.
June 15, 2025
Dr. Diaz is the best! So kind, caring, and knowledgeable!
June 15, 2025
I appreciate everything she has done for me over the years. Even if we disagree on a treatment, (I can be super stubborn) she finds a way to explain the risks and benefits. Never belittles me or makes me feel incompetent. I'm happy with these last results and look forward to whatever comes my way.
June 14, 2025
I drive 2 1/2 hours to see Dr. Diaz. She is amazing!
June 09, 2025
Dr. Diaz truly cares about my health and always looks for ways to get to the bottom of the issues.
May 19, 2025
Dr Diaz is wonderful. She's very thorough and open to listening to me about other options and concerns.
May 12, 2025
Great Doctor. Very understanding and caring.

Directory Disclaimers

This directory contains information about the provider members of Independent Health Care Associates, Avera Health and all Avera entities, members of the Avera Medical Group, and employed select providers with Avera McKennan, Sioux Falls, SD and Avera Marshall, Marshall, MN and physicians with hospital privileges at Avera St. Luke's, Aberdeen, SD; Avera Sacred Heart, Yankton, SD; Avera Queen of Peace, Mitchell, SD; Avera St. Mary's, Pierre, SD.

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