Introduction to Hormone Testing

 

January 16, 2026

Dear Friends,

For almost 30 years, we have offered the saliva and blood spot hormone tests of ZRT Laboratory on The Official Website of John R. Lee, M.D. Our partnership with ZRT Laboratory began with Dr. Lee himself, who was a friend and valued colleague of Dr. David Zava, the founder of ZRT Laboratory. With respect for this long partnership, we are announcing that for now, we are not selling ZRT Laboratory’s hormone tests on JohnLeeMD.com. In this letter, we will explain why we made this decision and how it affects you, our customers.

What ZRT Laboratory Has Announced

On January 15, 2026, ZRT Laboratory announced a number of changes to its saliva and blood spot tests. These include:

  • Changing the methods and technologies the company uses to test saliva and blood spot samples

  • Changing the hormone test kits it offers

  • Changing the names and prices of its hormone test kits

As a result of these changes, the hormone levels that these new tests report may not be the same as the hormone levels that ZRT Laboratory’s current tests report. In addition, customers who have relied on ZRT Laboratory’s tests for years will need to learn the company’s new lines of test kits along with their new names, select the new test kits they want to take, and deal with interpreting the potentially different hormone levels that the new tests report.

What This Means If You Have an Unused Test Kit

If you have a ZRT Laboratory test kit that you purchased from us or our business partner, Rupa Health, do not worry! ZRT Laboratory will accept your saliva and blood spot specimens and run the tests you ordered. However, ZRT Laboratory is encouraging all of its customers to use their test kits and send their samples to ZRT Laboratory no later than the end of February 2026. That is when the company plans to complete its transition to the new testing technologies and new lines of hormone tests with new names.

Our Response to ZRT Laboratory’s Announcement

ZRT Laboratory has told us it is making these changes to improve the accuracy of its tests and the number of testing options it can offer its customers. While this may be true, we expect these changes will cause confusion among users of ZRT Laboratory’s tests. That confusion may greatly increase the support users need to choose the right tests and interpret the test results.

While ZRT Laboratory’s announced changes may benefit its users in the long run, they make it hard for us to fully support our customers with its tests at this time. We will learn more about these changes, but for now, we’ve decided to stop selling ZRT Laboratory’s tests from JohnLeeMD.com, effective immediately.

While we cannot offer hormone tests at this time, we are open to offering tests in the future if they are in alignment with Dr. Lee’s research on hormone testing, and include the support our customers need to use the tests and interpret their results.

What You, Our Valued Customers, Can Do

We understand that this announcement may come as a shock to all of you who have relied on us for hormone tests over the years. We are sorry for any inconvenience this causes you.

We know that many of you are now wondering where you can purchase in-home hormone tests. We want to help you as best as we can, so we are studying the market to identify laboratories and vendors we can recommend to you. Our studies will take time and we do not yet have recommendations to make, so we ask you to wait as we look for reliable sources of quality hormone tests that we can support. If and when we find those sources, we will post information about them on this page. Please check this page regularly for announcements from us!

If you want to learn more about what ZRT Laboratory has announced, you can read the full announcement of the company by clicking here. You can also call ZRT Laboratory at (866) 600-1636 or email it at info@zrtlab.com to ask questions or tell them what you think of the announcement.

Finally, we thank all of you who have purchased ZRT Laboratory’s hormone tests from us. We were proud to provide these tests in support of your efforts to balance your hormones using Dr. Lee’s research and guidance. Please know that we will continue to offer you that research and guidance.

We will also continue to offer you access to natural progesterone creams and tens of thousands of other natural health products at discounted prices through our Web Shop on Fullscript and our Web Shop on iHerb.com. If you have not yet ordered from our Web Shops and enjoyed the savings they offer, we encourage you to do so. We remain committed to helping you balance your hormones safely and naturally, just as Dr. Lee taught us all.

Yours for Good Health,

The Official Website of John R. Lee, M.D., JohnLeeMD.com