Do You Gain Weight After Thyroid Surgery?

by | Sep 25, 2023 | Thyroid Health

Weight gain is a common concern for patients who get thyroid surgery or a thyroidectomy. Thyroid surgery is a procedure that removes the thyroid gland because of goiter, thyroid cancer, or Graves’ disease. These complications affect the production of thyroid hormones T3 and T4 that control the body’s metabolic activity.

After surgery, patients take tablets to replace the hormones. Patients who undergo thyroid surgery may experience weight gain post-surgery. However, it’s not clear if the weight gain is caused by thyroid surgery. Let’s explore the effects of thyroid surgery on weight gain.

What Do The Studies Show? 

A study published in 2018 sought to investigate weight gain changes after thyroid surgery among patients in Olmsted County, Minnesota. The study grouped placed the patients into groups. Group A had thyroid cancer while Group B had benign thyroid nodules, both treated with thyroid surgery. The study used underlying weight, BMI values, among other patient characteristics, to measure weight gain after surgery. The scientists compared values between 6-12 months after surgery, 12-24 months post-surgery, and 24 -36 months after surgery.

16% of the patients gained 5 and 10 kg within three years after surgery. The meta-analysis shows that patients with thyroid cancer who underwent surgery and had long follow-ups gained significant weight in the first two years post-surgery. However, there was no significant weight gain three-five years after surgery. Patients with benign nodules also gained weight two years post-surgery.

Do You Gain Weight After Thyroid Surgery

For comparison purposes, the study also investigated a third group, Group C. These were patients with benign nodules that didn’t get surgery. The results indicate no clinically significant weight gain between patients in Group B and Group C. The study concluded that weight gain after surgery is not related to thyroid surgery.

Another study also found no significant changes in the weight, BMI, and BMI percentiles among study subjects who had thyroid cancer, thyroid nodules, or goiter. The study made adjustments for age, weight, and other variations among the patients but did not establish a direct link between thyroid surgery and weight gain.

What Happens If I Gain Weight After Thyroid Surgery?

While studies do not have a conclusive report on weight gain after thyroid surgery, patients gain weight. As such, it’s essential to understand how to manage weight. To find a weight management solution, let’s first explore the significance of thyroid hormones in metabolism.

How Does The Thyroid Regulate Metabolism? 

The thyroid is a small gland in the human body that produces thyroid hormones.

  • T3 (Triiodothyronine)
  • T4 (Thyroxine)

These hormones play a crucial role in human metabolism. The thyroid gland releases these hormones into the circulatory system. Another gland in the endocrine system, the pituitary gland, triggers thyroid hormone release by releasing Thyroid Releasing Hormone (TRH).

Thyroid hormones are active in almost every cell in your body. They increase metabolism in the cells. Think of the thyroid hormone as an activator for glucose and fat burning to provide your body with energy. With a high basal metabolic rate (BMR), you can create energy even if you’re not physically active. In short, your body needs thyroid hormones to remain active, energetic, and warm.

When you have thyroid problems, your body either has hyperthyroidism or hypothyroidism. In hypothyroidism, the thyroid gland releases little thyroid hormones into the bloodstream. The result is lowered metabolic activity.

Without enough energy for your cells, you may experience:

  • Fatigue
  • Mood swings
  • Drowsiness
  • Memory problems
  • Irritability
  • Cold intolerance
  • Hair loss
  • Weight gain

Hyperthyroidism, on the other hand, increases the amount of thyroid hormones in the bloodstream. As such, the BMR is higher than usual, which means your cells are more active than required. You may experience symptoms such as:

  • General anxiety
  • High blood pressure
  • Irregular heartbeat
  • Loss of concentration and sleep
  • Weight loss

Generally, wrong levels of thyroid hormones in your blood affect weight loss and gain. Since it’s unclear if thyroid gland removal plays a role in weight gain post-op, it’s best to find ways to regulate your metabolic activity for healthy weight levels.

Managing Your Metabolic Activity after Thyroid Surgery 

After surgery removal, you undergo replacement therapy by taking tablets. The tablets introduce thyroxine to your blood system, depending on your needs. Tests before and after surgery help your physician recommend the correct dosage. However, this takes time.

In this testing period, irregular thyroid hormone levels affect your BMR. If the thyroid hormones are too low, you may experience hypothyroidism symptoms, including weight gain. If the thyroid hormone levels are too high, you may experience hyperthyroidism symptoms, including weight loss.

Medication Adherence 

Medication adherence is taking your hormone therapy medication as prescribed- in the correct dosage, right time, and as frequently as recommended. Medication non-adherence causes fluctuations in your BMR and TSH levels. Forgetting to take medication, taking medication at the wrong time of the day, or taking the wrong dosage can disrupt body activity. It takes a while for hormone levels to adjust.

Regulating Your Diet 

If you’ve noticed weight gain, it’s time to start watching what you consume. Reduce your consumption of complex carbohydrates, fatty and sugary foods. Your body has a hard time metabolizing these foods and turning them into glucose for immediate use. Increase your protein consumption, especially lean meats, and add vegetables and low-fat products.

Watch when you eat to ensure that your body gets the energy it requires for daily activities. Focus your meals in the morning and lunchtime, and keep your meals light in the evenings. Give your body at least two hours to complete digestion before going to sleep.


Your resting metabolic rate (RMR) is different from your Thermic effect of exercise (TEE). The latter is the number of calories you burn when you increase your BMR. You can raise your BMR by exercising regularly. Activity in your muscles encourages fat and glucose burn to prevent weight gain.

Stay Fit After Thyroid Surgery 

AT C/V ENT Surgical Group, we provide thyroid removal surgery and therapy replacement. We understand how frustrating it can be to live with thyroid diseases. Our goal is to treat and advise you to avoid weight gain after thyroid surgery. If you have any questions about thyroid surgery, contact us today.