GradedHealth

Can you take levothyroxine with breakfast? A 2026 trial of 88 adults tested it

In an 88-person trial, levothyroxine with breakfast plus a 15% higher dose kept thyroid levels as stable as fasting dosing, and most people preferred it.

Published October 2026

Short answer

Yes, with a dose change: with a 15% dose increase, levothyroxine with breakfast kept thyroid levels as stable as fasting in one open-label trial. Early but encouraging; dose changes need a doctor's guidance. Evidence grade C (Limited). One open-label randomised trial of 88 people at a single centre; downgraded for small sample (too small for a formal non-inferiority test) and open-label design.

Key takeaways

  • Standard advice is to take levothyroxine on an empty stomach, but fasting dosing is burdensome and may reduce adherence [1].
  • In 88 adults with well-controlled hypothyroidism, TSH stayed stable in 74.4% of those taking levothyroxine fasting and 73.3% of those taking it with breakfast plus a 15% higher dose [1].
  • Preference for nonfasting intake was stronger in the breakfast group (76.2%) than in the fasting group (44.2%), and 88.9% chose to continue nonfasting intake at the end [1].
  • More people in the breakfast group reported better well-being (33.3% vs 16.3%), but the difference was not statistically significant [1].
  • Other trials found that taking levothyroxine at bedtime or an hour before the main meal also kept thyroid levels in range, so timing options exist [2][3].

What the study did

Levothyroxine, a thyroid hormone tablet taken for an underactive thyroid, is usually taken fasting to absorb it well, but this can be burdensome and may reduce adherence [1]. Researchers in the Netherlands randomly assigned 88 adults with well-controlled hypothyroidism (median age 62, 81% women) to keep taking it fasting, 30 to 60 minutes before breakfast, or to take it with breakfast with a 15% higher dose [1]. Thyroid blood tests were repeated every 6 weeks, and doses were adjusted if needed, for up to 24 weeks. The main goal was stable TSH, the main thyroid test: two readings in a row in the normal range and within 1 mIU/L of the starting level [1]. After the first period, people in the fasting group were invited to switch to breakfast dosing [1].

What it found

TSH stability was about the same in both groups: 74.4% (95% confidence interval 61.0 to 88.0) with fasting dosing and 73.3% (60.0 to 87.0) with breakfast dosing. Similar results were seen in the group that switched [1]. In the breakfast group, 33.3% reported improved well-being, against 16.3% in the fasting group (P = .07, not statistically significant). Preference for non-fasting intake was stronger in the breakfast group (76.2% vs 44.2%), and by the end 88.9% chose to continue nonfasting intake [1].

How it fits

Other trials have looked at when to take the tablet rather than whether to eat. A three-period crossover trial in 84 people found that taking levothyroxine half an hour before breakfast, an hour before the main meal or at bedtime gave similar thyroid levels [2]. An older crossover trial of 105 people found that bedtime dosing lowered TSH by 1.25 mIU/L compared with morning dosing, with no change in quality of life [4], but a 2025 meta-analysis of eight evening-versus-morning trials found no significant difference in TSH change [3]. The authors of the meta-analysis concluded that regimens may be tailored to patient convenience [3].

Limits

The trial was open-label, so patients and doctors knew who was in which group, and it was done at one hospital with 88 people, which the authors note was too small to meet the threshold for a non-inferiority trial [1]. It only included adults whose thyroid levels were already well controlled, and it excluded pregnancy, breastfeeding, malabsorption disorders such as coeliac disease and some other conditions [1]. The 15% dose increase was chosen empirically, and iron, calcium and acid-reducing medicines were allowed with a 4-hour gap from levothyroxine [1]. The paper drew a letter to the editor and a reply from the authors [5][6]. This is not medical advice: levothyroxine has a narrow safe range, so changing when or how you take it, or its dose, should be done with your prescriber, who can arrange follow-up blood tests.

Go deeper

  • Breakfast — Eating breakfast is linked to lower heart-disease risk in large observational studies, which cannot prove cause.

References

  1. Fasting vs Nonfasting, Dose-adjusted Levothyroxine Ingestion in Hypothyroidism: A Randomized Clinical Trial.. J Clin Endocrinol Metab, 2026.
  2. Effect of timing of levothyroxine administration on the treatment of hypothyroidism: a three-period crossover randomized study.. Endocrine, 2018.
  3. Effects of timing and scheduling in levothyroxine adherence to hypothyroidism control: Meta-analysis with trial sequential analysis of Randomized Clinical Trials.. Endocrine, 2025.
  4. Effects of evening vs morning levothyroxine intake: a randomized double-blind crossover trial.. Arch Intern Med, 2010.
  5. Letter to the editor from Virili et al: "Fasting vs non-fasting, dose-adjusted levothyroxine ingestion in hypothyroidism: a randomized clinical trial".. J Clin Endocrinol Metab, 2026.
  6. Response to Letter to the Editor "Fasting vs non-Fasting, dose-adjusted levothyroxine ingestion in hypothyroidism: a Randomized Clinical Trial".. J Clin Endocrinol Metab, 2026.