Levothyroxine as Adjuvant to a Hypocaloric Diet for the Treatment of Obesity.

Obesity is a chronic disease with high relapse rates after initial weight loss. Thyroid hormones modulate energy expenditure, body composition, and thermogenesis; higher TSH within the reference range and subclinical hypothyroidism have been associated with adverse metabolic profiles and weight gain. These signals suggest the thyroid axis could influence weight-loss response and subsequent regain. Levothyroxine (LT4) is widely used for hypothyroidism; evaluating its adjuvant role in obesity management is clinically relevant. This is a phase III, randomized, double-blind, placebo-controlled, multicentre clinical trial conducted in five Spanish hospitals. A total of 286 adults (25-60 years) with grade I-II obesity will be enrolled if they have subclinical hypothyroidism (TSH 5-10 mIU/L with normal peripheral hormones) or are euthyroid with TSH in the highest tertile of the reference range. Participants are randomized 1:1, stratified by age, sex, and BMI. Intervention: LT4 88 µg once daily or matching placebo for 9 months. During months 0-3, all participants receive a structured hypocaloric Mediterranean diet (≈600 kcal/day deficit; macronutrients 45% carbohydrates, 35% fats, 20% proteins) plus standardized physical-activity advice. From months 3-9, lifestyle support continues with a normocaloric Mediterranean diet. Physical-activity guidance targets ≥150 min/week of moderate-to-vigorous activity (spread over ≥3 days) and 2-3 resistance sessions/week. Primary endpoint (3 mont…

This description comes directly from the study's public registry record.

Contact details are listed per location below or on the registry record.

Always discuss trial participation with your own doctor first.

Get one email when the public record changes — results posted, or the study's status changes. Nothing else, ever.

We email about this public record only. Unsubscribe anytime with one click. Never medical advice.