News & Events

by Kimberly Dorris, Executive Director, GDATF

I’m old enough to remember the classic coffee jingle, “the best part of waking up is Folgers in your cup”. I’ve never been a morning person, so I’d say that’s about as close to truth in advertising as you can get. But when I found myself diagnosed with hypothyroidism (after two years of remission and seven years of methimazole before that), I discovered that the worst part of waking up was delaying coffee and breakfast for 60 minutes* after taking my replacement hormone!

*EDITED TO ADD: The 60-minute time frame reflects the guidance I was initially given, as well as the recommendation in the 2014 American Thyroid Association guidelines for treatment of hypothyroidism. (These guidelines are currently going through an update process to include the latest research.) Thanks to the eagle-eyed community members who pointed out that the labels for many brand name and generic levothyroxine products recommend dosing 30-60 minutes prior to breakfast.

New Research Presented at the American Thyroid Association (ATA) Annual Meeting

Representatives from the GDATF attend meetings every year for the American Association of Endocrine Surgeons (AAES), the Oculofacial Society (formerly the American Society of Ophthalmic, Plastic, and Reconstructive Surgery), and the American Thyroid Association (ATA). These meetings are held in different locations throughout the country and allow us to connect with physicians to let them know about our patient services, as well as to get updates on the latest research.

As I scanned the program for this year’s ATA Annual Meeting (held September 10-14 in Scottsdale, AZ), one presentation in particular caught my eye: “Fasting vs. non-fasting levothyroxine ingestion in hypothyroidism: a randomized controlled trial.”

The program was presented by lead author Dr. Jeresa Willems, from Zuyd Thyroid Center in the Netherlands. Dr. Willems started the program with an informal show-of-hands survey of the audience (mostly endocrinologists who specialize in thyroid dysfunction) to determine what advice they were giving patients regarding the timing of levothyroxine. The vast majority of attendees recommended dosing in a fasting state. The purpose of this delay is to maximize the absorption of levothyroxine; Dr. Willems noted that absorption is affected by pH levels in the stomach.

You might remember learning about the pH scale in science class or doing a litmus test – where a strip of color-coded filter paper shows if a substance is acidic (low pH, like lemon juice) or basic (high pH, like ammonia). In a fasting state, your stomach has an acidic environment, which is the ideal condition for absorption of levothyroxine. Food consumption increases the pH, potentially decreasing absorption. In addition, a very small, but interesting study from 2008 found that the absorption of levothyroxine in the small intestine could be reduced by drinking coffee or espresso at the same time (or shortly after) taking levothyroxine.

So the reasoning behind the delay makes sense, but how does the waiting game play out in practice? Dr. Willems and colleagues had previously studied this, publishing the findings in 2024 in the Journal of the Endocrine Society. Approximately half the study patients found that the delay was a burden. One fourth of the participants ensured compliance by skipping breakfast, and 13.4% of participants would forget their medication entirely! (Another issue – not discussed during the presentation – is that some patients choose to set their alarm early, take the medication, reset the alarm, and then go back to bed, potentially disrupting their sleep cycle.)

After reviewing the study results, Dr. Willems and a new team (including some of the authors on the prior project) set out to test a potential new approach. The INFINITY study was designed to determine if levothyroxine could be taken with breakfast while keeping TSH levels stable.

For an excellent write-up that digs into the INFINITY study details, you can check out this Medscape piece by Nancy Melville. (Login might be required to view, but setting up an account should be free.) In short, the team recruited 88 patients and compared one group taking levothyroxine using the typical fasting regimen before breakfast to a second group who took the medication at the same time as breakfast, but with a 15% increased dose. The team found that there were no significant differences between the two approaches in terms of TSH stability. After the initial 24 weeks, the fasting group was invited to test the new regimen, and close to 90% of those patients chose to continue taking their levothyroxine with breakfast.

At the end of the talk, Dr. Willems did another informal show-of-hands poll – this time asking the attendees who would be willing to try the new dosing regimen with their patients. A lot of hands went up! 

Next Steps – And Other Options

Of course, best practices are developed by reviewing an entire body of evidence, not just a single study. In particular, one attendee during the Q&A session pointed out that it’s possible that the form of levothyroxine given to patients in the Netherlands might be absorbed differently than the commercially available preparations in the USA. In addition, Dr. Willems noted that the majority of patients in the study had the same breakfast every day, and the approach might not work as well for someone whose breakfast routine has less consistency.

And there are other factors that can affect absorption. For example, patients are advised to wait for four hours after taking levothyroxine before ingesting iron, soy, and calcium supplements. And the prescribing information for both Synthroid and Tirosint note that soybean flour, cottonseed meal, walnuts, and dietary fiber can decrease absorption – and that grapefruit juice can delay absorption. Patients with specific gastrointestinal conditions can also experience decreased absorption.

Still, this approach presents an interesting option that might help reduce reported patient burden with a 30-60 minute delay. If you are like me and “hate the wait”, the following might also be of interest:

• A small number of studies have found a benefit to taking levothyroxine before bedtime. For patients using this approach, the American Thyroid Association suggests three hours after the evening meal. (Of course, this would be a challenge for those who typically eat a late dinner or get the late-night munchies!)
• A 2023 label change for Tirosint-SOL (a liquid preparation of levothyroxine that is packaged in tiny vials) notes that Tirosint-SOL can be taken 15 minutes before breakfast.
• A presentation at the 2022 annual meeting of the Endocrine Society noted that another liquid levothyroxine product, Thyquidity, could be taken within 5 minutes of coffee with no significant impact to absorption. (One of the challenges here is that people enjoy their coffee differently – for example, do you like yours straight up or loaded with cream and sugar?)
• Based on the results of a GDATF 2018 Facebook poll, some of our community members noted that they go ahead and take their levothyroxine if they happen to wake up in the middle of the night. (But be sure to have a system for remembering if you still need to take the medication in the morning – perhaps put out a full glass of water before bedtime.)

Have you tried one of these approaches with your levothyroxine? Has your doctor offered some other suggestions not mentioned in this post? Use the GDATF contact form and drop us a note!