Is your Thyroid the reason you’re not losing weight?

Has losing weight been a struggle despite your best efforts? Your Thyroid, a small gland in your neck, could be the culprit behind your weight loss woes. Understanding how your Thyroid affects weight management may be the missing link in your weight loss puzzle. This article will explore the relationship between your Thyroid and weight loss, shedding light on its science and providing practical insights.

The Thyroid Gland: The Weight Influencer

The thyroid gland looks like a butterfly, is located in the front of the neck below the larynx, or the voice box, and is vital in maintaining overall health. It secretes two hormones (triiodothyronine, T3, and Thyroxine, T4)  that control metabolism—the rate at which your body burns calories for energy. They also regulate body temperature, brain development, cholesterol levels, menstrual cycle, muscle elasticity, skin dryness, etc. When the Thyroid isn’t functioning optimally, it can disrupt the delicate energy balance and make weight loss challenging; it can also lead to fatigue, dry skin, and difficulty concentrating.

Hypothyroidism: The Weight Loss Barrier

Hypothyroidism, an underactive thyroid condition, occurs when the thyroid gland fails to produce enough hormones. When the thyroid hormones are low, it can slow down your metabolism, leading to weight gain and difficulty shedding excess pounds. Hypothyroidism is often accompanied by symptoms such as fatigue, weight gain, cold intolerance, joint and muscle pain, constipation, dry skin, decreased sweating, heavy or irregular menstrual periods, depression, and slowed heart rate

To diagnose Hypothyroidism, your healthcare provider may request a blood test to measure thyroxine and thyroid-stimulating hormone (TSH) levels.

Causes of Hypothyroidism

1. Hashimoto’s disease

This is the most prevalent cause of Hypothyroidism. It occurs when the immune system attacks and damages the thyroid gland. Over time, this autoimmune response impairs the gland’s ability to produce sufficient thyroid hormones, resulting in an underactive thyroid.

2. Thyroiditis

Thyroiditis is the inflammation or swelling of the thyroid gland. This causes stored thyroid hormone to leak out of the thyroid gland. Initially, the leakage raises hormone production, leading to hyperthyroidism—when thyroid hormone levels are too high. Most people develop Hypothyroidism before the Thyroid is completely healed.

3. Surgical removal of the Thyroid

The surgical removal of a part of the thyroid gland (thyroidectomy) or radiation therapy aimed at the neck area to treat hyperthyroidism, goiter, or thyroid cancer may disrupt thyroid function and lead to Hypothyroidism. In these cases, thyroid hormone replacement therapy is typically necessary.

4. Medications

Some medications can interfere with thyroid function and contribute to Hypothyroidism. For instance, Lithium, a bipolar disorder medication, can affect hormone production and result in an underactive thyroid. Certain medications used to treat cancer and heart disease may also have similar effects.

5. Congenital Hypothyroidism

Some babies are born with a thyroid that is not fully developed or does not function properly. This condition is known as congenital Hypothyroidism. Early detection and prompt treatment are essential to prevent adverse effects on growth and development.

6. Pituitary or Hypothalamic Disorders

Hypothyroidism can also be from the pituitary gland or hypothalamus; these organs regulate the release of thyroid hormones. If these glands do not release adequate amounts of the hormones that stimulate the release of thyroid hormones, it may result in decreased production of thyroid hormones.

7. Iodine Deficiency

Although rare, Hypothyroidism may be caused by too little iodine. Iodine is an essential mineral required for the production of thyroid hormones. In regions with insufficient dietary iodine intake, the thyroid gland may be unable to synthesize adequate hormone levels, leading to Hypothyroidism. However, iodine deficiency is rare in areas where iodized salt or iodine-rich foods are consumed.

The Link between Hypothyroidism and weight gain

  • Some research suggests that decreased thyroid function could be responsible for increasing weight and body mass index through changes in metabolic rate.
  • People with an underactive thyroid experience difficulties in losing weight, which emphasizes the impact of thyroid function on weight management.
  • Most people with Hypothyroidism tend to experience abnormal weight gain and difficulty losing weight until hormone levels stabilize. Individuals with Hypothyroidism have a greater risk of cardiovascular disease than the risk associated with weight gain alone. Low levels of thyroid hormones lead to a higher blood lipid profile, increased blood pressure, and cell damage due to inflammation.
  • Hypothyroidism also affects carbohydrate metabolism and profoundly affects glucose control, making it a risk factor for Type 2 diabetes.


Your healthcare provider may recommend hormone replacement therapies such as Levothyroxine and other replacement therapies to manage Hypothyroidism; dosage depends on your TSH level upon diagnosis, age, gender, severity of symptoms, and other associated health conditions.

Nutrition Tips for Managing Weight with Hypothyroidism

  •  Focus on healthful behaviors: Don’t fixate on the numbers on the scale; work with your dietitian to gradually change your diet by including whole grains, lean proteins, fruits, vegetables, healthy fats, and other nutrient-rich foods.
  • Portion Control: Be mindful of your portion sizes to avoid excessive calorie intake. Practice mindful eating, and listen to your body’s hunger and fullness cues. Also, avoid stress and emotional triggers that can cause you to overeat.
  • Exercise: Exercise can improve symptoms of fatigue and depression and reduce weight gain. Engage in aerobic and strength training exercises and do body stretches to relax from stress.

Key Nutrients to Support Optimal Thyroid Function

  • Iodine: Include iodine-rich foods in your diet, such as iodized salt, fish, cheese, milk, seaweed, eggs, and beef liver, to enhance thyroid hormone production.
  • Vitamin D: People with thyroid disorder usually have low levels of Vitamin D. Boost your vitamin D levels by incorporating fatty fish, milk, dairy products, eggs, and mushrooms into your meals.
  • Selenium: Selenium-rich foods such as fish, Brazil nuts, tuna, crab, and lobster can contribute to properly functioning thyroid gland.
  • Vitamin B12:People with Hypothyroidism are at risk of Vitamin B12 deficiency. Ensure sufficient vitamin B12 levels by including sardines, salmon, organ meats (such as liver), muscle meat, and dairy products.
  • Probiotics:  Probiotics enhance gut health by increasing the good bacteria in the gut. Some studies show that flourishing gut health impacts how well the Thyroid absorbs and uses micronutrients.


While medication may be necessary to address the thyroid hormone imbalance, working closely with your dietitian can optimize your nutrient intake, support healthy weight loss, reduce stress, and reduce the risk of hypertension, diabetes, and heart disease associated with Hypothyroidism.



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