Micronutrients and Thyroid Recovery After Sleeve Gastrectomy: AJS | April 2026

Introduction

Bariatric surgery, particularly sleeve gastrectomy, is increasingly recognized not only for weight loss but also for its metabolic benefits, including improvement in endocrine disorders such as hypothyroidism. While many patients experience normalization of thyroid function after surgery, predicting which patients will achieve thyroid-stimulating hormone (TSH) remission remains unclear. Emerging evidence suggests that micronutrient status—especially vitamin D and vitamin B12—may play a role in endocrine recovery and metabolic regulation.

Problem Statement

There is a lack of reliable preoperative predictors to identify which hypothyroid patients will achieve TSH remission after sleeve gastrectomy.

Summary

This study demonstrates that preoperative levels of vitamin D and vitamin B12 are strong predictors of TSH remission following sleeve gastrectomy. Patients with higher baseline levels of these micronutrients had significantly higher rates of remission at both 6 and 12 months. Notably, up to 77.5% of patients achieved TSH normalization by 12 months, with many able to reduce or discontinue levothyroxine therapy, and none requiring dose escalation.

Importantly, micronutrient levels outperformed traditional predictors such as age, sex, and BMI, highlighting a potentially modifiable factor in preoperative optimization. Both vitamin D and B12 showed strong predictive accuracy, suggesting a clinically meaningful role in patient selection and counseling.

From a practical standpoint, this study supports routine assessment and correction of micronutrient deficiencies before bariatric surgery. It also opens the possibility that optimizing nutritional status may enhance endocrine recovery, moving toward a more personalized and proactive perioperative strategy.