Thyroid pill plus diet may boost weight loss in obesity, new trial suggests

NCT ID NCT07332273

First seen Jun 24, 2026 · Last updated Jun 27, 2026 · Updated 2 times

Summary

This phase 3 trial tests whether adding a low dose of levothyroxine (a thyroid hormone) to a Mediterranean diet and exercise program helps adults with obesity lose more weight and keep it off. The study enrolls 286 people aged 25-60 with grade I-II obesity and higher-than-normal thyroid hormone levels. Participants take either levothyroxine or a placebo daily for 9 months, while all follow the same lifestyle program. Researchers will measure weight, body fat, and metabolic health at 3 and 9 months.

What this could mean

Our plain-language read of the trial. This is informational only — not medical advice or a prediction.

Active substance

levothyroxine (thyroid hormone)

What this could lead to

If it works, this could point toward a new way to boost weight loss and prevent regain in people with obesity who have higher thyroid hormone levels.

What could go wrong

This is still an early-phase trial with 286 people, so results may not apply to everyone. Levothyroxine can cause heart palpitations or bone loss if overused.

Disclaimer Read more

This is a summary of the original study . Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.

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Conditions

The condition(s) this trial relates to.

Obesity obesity disorder

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

Contacts and locations

Locations

  • Hospital Clínico Universitario de Valladolid

    NOT_YET_RECRUITING

    Valladolid, Spain

  • Hospital Puerta del Mar

    NOT_YET_RECRUITING

    Cadiz, Spain

  • Hospital Reina Sofía

    NOT_YET_RECRUITING

    Córdoba, Spain

  • Hospital Universitario Virgen de la Victoria

    RECRUITING

    Málaga, Spain

    Contact Phone: •••-•••-•••• Email: •••••@•••••

  • Hospital Universitario de Jaén

    NOT_YET_RECRUITING

    Jaén, Spain