About Us

Experienced clinicians to answer health care provider questions is another benefit of working with ZRT Laboratory.

Our docs are available Monday through Friday 9:00am - 5:00pm – free of charge – to answer questions including who to test, when to test, how to interpret our results and how to handle your most challenging hormone cases.

Founder Of ZRT Laboratory, Dr. David Zava

Dr. David Zava, a biochemist by trade and a teacher at heart, is animated when he talks about his work. He didn’t start out trying to build a company — as a researcher, he wanted to provide health care practitioners and patients with a deeper understanding of the role hormones play in wellness.

The more he studied, the more test results he reviewed, and the more patient stories he heard, the more he knew he needed to channel his knowledge into something that enables people to be actively involved in their own health.

To this day, he’s continually searching to understand more fully how the world around us impacts our wellbeing, and how our lifestyle choices, environment and genetics impact the delicate balance of our hormones.

His hands-on approach trickles down through ZRT Laboratory, so much so that the company is renowned for the way it supports people and their health on such a personal level.

“There is no other reason to keep doing the work unless we find out a way to make the world a better place.”

ZRT Laboratory embodies Dr. Zava’s vision, and is recognized the world over as a team devoted to providing the most accurate results with the most educated insight into their meaning.

Dr. Alison McAllister is the lead clinical consultant for ZRT. She sees patients in her own practice several days a week, and has worked with ZRT for over 17 years – helping hundreds of doctors understand hormone balance and the role that hormones, neurotransmitters and elements play in overall health. She is an expert in thyroid function, fertility and PCOS. In addition, Dr. McAllister also regularly lectures for groups such as the A4M and IFM at industry conferences. 

Dr. Sherry LaBeck has been with ZRT for over 12 years. Prior to being a clinical consultant she taught at the National University of Natural Medicine in Portland OR and the Southwest College of Naturopathic Medicine in Tempe AZ. Her mission is to continue to expand education about hormones for health care providers around the country.

Dr. Beth Baldwin earned her N.D. at Bastyr University. She has since worked in private practice, community health and clinical research, focusing on women’s health throughout the lifespan, bioidentical hormone replacement and neurodevelopmental disorders. As a member of ZRT Laboratory’s Clinical Consultant team, Dr. Baldwin shares her knowledge to promote safe approaches to hormonal health.

Dr. Kate Placzek

Dr. Kate Placzek is the Senior Research Scientist at ZRT Laboratory. She combines clinical observation with published research findings to create and develop innovative functional medicine test profiles used by practitioners around the globe. Prior to joining ZRT Laboratory she received her doctorate from Purdue University in Medicinal Chemistry and Molecular Pharmacology; and performed her postdoctoral studies at Oregon Health and Science University.

Margaret N. Groves, M.Phil., ELS

Margaret N. Groves, M.Phil., ELS is a scientific and technical writer for ZRT Laboratory, with a background in biochemistry and cancer research. She researches the medical literature on topics relevant to ZRT testing products, contributes to the ZRT product information supplied to health care providers, and as part of the research team helps with writing up ZRT’s research studies for publication.

Dr. Allison Smith

After completing her N.D. at the National University of Natural Medicine in Portland, Oregon, Allison Smith, ND worked in private practice focusing on primary care, women’s health and dermatologic laser therapy. During her time with ZRT Laboratory’s Clinical Consultant team, Dr. Smith's focus shifted to fostering the medical field’s understanding of safe hormone therapies, sharing integrative approaches to health, and assisting in dissecting tough cases.

Jim Paoletti, BS Pharmacy, FAARFM, FIACP

Jim Paoletti is an independent clinical consultant. He is a nationally recognized expert with over 38 years of experience with bioidentical hormone therapies in clinical practice. Jim previously served as Director of Provider Education for ZRT Laboratory, and as consultant and Education Director for Professional Compounding Centers of America (PCCA). He is a graduate and former faculty member of the Fellowship of Anti-aging and Functional Medicine.

Theodore Zava

Theodore Zava is the Laboratory and Quality Systems Manager at ZRT Laboratory. He has over 15 years of experience bringing new and innovative clinical tests to market. Past and current projects include dried urine and blood spot heavy metal and essential element testing, thyroid hormone analysis and menstrual cycle mapping.

Dr. James Greenblatt

Dr. Greenblatt is board-certified in child and adult psychiatry. Dr. Greenblatt lectures extensively throughout the United States and Canada on integrative therapies for mental health. He is also the author of six books including those on depression, eating disorders and ADHD including “Answers to Anorexia” and “The Breakthrough Depression Solution,” which outlines a personalized nine-step method for beating the physical causes of depression.

Ingrid Edstrom, FNP, M.Ed

Ingrid Edstrom is the President and Author of Proactive Breast Wellness LLC, and has become a thought leader in the pursuit of breast cancer prevention. Ingrid developed and has been providing the Proactive Breast Wellness program for her patients on a one to one basis since 2006. Ingrid’s clinical practice has established a correlation between toxic exposure to herbicides/ pesticides/ bovine growth hormones resulting in abnormal Thermography scans.

Dr. Felice Gersh

Dr. Gersh is Board Certified in both OB/GYN and in Integrative Medicine. She received her undergraduate degree from Princeton University, a medical degree from the University of Southern California School of Medicine, and a 2 year Fellowship in Integrative Medicine at the University of Arizona School of Medicine. Dr. Gersh has dedicated her career to women, focusing on the aspects of women’s health which are unique, under-appreciated, and poorly managed.

Alyssa Burns Hill, PhD, MSc, FRSPH, MIHPE

Alyssa Burns-Hill, PhD, MSc, FRSPH, MIHPE, is an internationally recognized natural health Hormone Health Specialist and a scientist and practitioner of health in its broadest sense. She works with many people around the world, helping them rediscover not only good health naturally, but also a better understanding of themselves.

Christina Cowger, MA, LMFT

Christina has worked within the integrative medicine field for over two and a half decades. She holds a masters level degree with a focus on Health Education and Psychopharmacology. Christina is a licensed mental health practitioner who has lectured throughout the West Coast on topics such as mood, anxiety, stress, depression, trauma and addiction. Throughout her career she has consulted with addiction recovery centers on integrating a mind-body approach to recovery.

Dr. Paul Savage

Dr. Savage has practiced integrative medicine for over 5 years and is nationally acknowledged as an expert in women’s health and hormones. He was certified in integrative medicine at George Washington University, and is the founder of Chicago Integrative Care. Dr. Savage is a fellow of American Academy of Anti-Aging and Regenerative Medicine, as well as the American College of Emergency Medicine.

Dr. Peter Bongiorno

Dr. Peter Bongiorno co-medical director of Inner Source Health, with practices in New York City and Long Island. Dr. Bongiorno has published many books focus on using natural medicines for mental health care. He is the author of Healing Depression - the first comprehensive textbook designed to teach physicians about natural medicine for mood support, Holistic Solutions for Anxiety and Depression, and How Come They’re Happy and I’m Not.

Dr. Robert Zembroski

Dr. Zembroski is a physician specializing in functional medicine, board-certified chiropractic neurologist, clinical nutritionist, best-selling author, and motivational speaker. He is founder of the Cancer Victor Protocol®, and is the director of the Darien Center for Functional Medicine.

Dr. Thomas Guilliams

Dr. Guilliams earned his doctorate from the Medical College of Wisconsin where he studied molecular immunology. Since 1996, he has spent his time studying the mechanisms and actions of natural-based therapies, and is an expert in the therapeutic uses of nutritional supplements. Dr. Guilliams is a faculty member of the Fellowship in Anti-aging Regenerative and Functional Medicine (A4M).

Dr. Zane Hauck

Dr. Zane Hauck is a research scientist and mass spectrometry supervisor at ZRT, specializing in clinical testing of hormones, neurotransmitters, and biomarkers of health. He earned his PhD in Pharmacognosy from the University of Illinois at Chicago under the tutelage of Dr. Richard van Breemen. He is a member of the endocrine society and has published in journals including Rapid Communications in Mass Spectrometry and Journal of Analytical Chemistry.

Kori Wallace

Kori Wallace, PMP, has been with ZRT for over 15 years. During that time, she has enthusiastically filled roles in nearly every area of the business. As Director of Operations, her primary responsibility is oversight of inter-departmental collaborative efforts, including project management, new product launches, business reporting, process improvement initiatives and quality assurance. She is a former US Peace Corps volunteer who loves travel and nature.

Nina Silberstein, BA

Nina Silberstein, BA, is an editor and writer at ZRT Laboratory. She has a background in medical writing and editing, copyediting, proofreading, feature and news writing, advertising copywriting and assisting in the publication process for digital and traditional media. Her published work has appeared in print magazines, newspapers, journals, newsletters and online.

Pattie Ptak

Pattie Ptak founded Practice on Purpose in 2012 to help doctors in private practice streamline their procedures, leverage their time, and create systems for a more efficient and profitable practice. Pattie also teaches practice management for both the IFM and the A4M, and is on the Board of Directors of the Institute For Natural Medicine.

Theodore Brandon

Theodore Brandon is a mass spectrometry supervisor at ZRT Laboratory. After receiving his degree, he worked in a mass spectrometry core facility at The Scripps Research Institute. Ted was a primary researcher/developer for the blood spot 25-hydroxyvitamin D assay (first of its kind) by LC-MS/MS, the dried urine steroid hormone metabolites assay (first of its kind) by GC-MS/MS and the dried urine neurotransmitters assay (also first of its kind) by LC-MS/MS.

Tracy Tranchitella, ND

Dr. Tracy Tranchitella received her naturopathic doctorate degree in 1998 from Southwest College of Naturopathic Medicine. For over 20 years, she has practiced general naturopathic medicine with an emphasis on women’s health, adrenal, thyroid and sex hormone balance, digestive issues, autoimmune disease and metabolic disorders. For over a decade, Dr. Tranchitella provided clinical consultations for a functional medicine laboratory, guiding practitioners through interpretation and treatment considerations as well as developing test guides, products and treatment protocols. She cofounded Integrative Medicine Academy which provides comprehensive functional medicine courses on various topics. Dr. Tranchitella has recently joined ZRT Laboratory to develop educational content on a variety of topics with the goal of providing information that is clear and actionable for both practitioners and patients.

L. Kroon, Editor

Mr. Kroon is the editor of The Official Website of John R. Lee, M.D. Right up to the moment of his death in 2003, Dr. Lee, dedicated his life to helping women and men overcome health issues related to hormone imbalances. His books have made millions aware that there are safe, natural alternatives to synthetic hormones and their dangerous side effects. The Official Website of John R. Lee, M.D. is dedicated to continuing Dr. Lee’s groundbreaking work. Its goal is to help both women and men achieve hormone balance and experience optimal health through safe, natural means.