Hypothyroidism (Underactive Thyroid): Symptoms, Causes, Types and Diet to Follow

Hypothyroidism is a health condition arising from an underactive thyroid gland that fails to produce enough thyroid hormones. This may lead to sudden weight gain, tiredness, and cold sensitivity in patients. The prevalence of hypothyroidism in India is as high as 11%. In other words, 1 in 10 people suffer from it every year.

Symptoms of Hypothyroidism

The symptoms often develop slowly over time or sometimes even years. The primary symptoms include:

1. Weight gain

2. Feeling weak and tired

3. Higher cholesterol levels

4. Depression

5. Frequent and heavy menstrual periods

6. Decreased sexual interest

7. Sensitivity to cold temperatures

8. Constipation

9. Hair fall

10. Drooping eyelids and puffiness in the face and eyes

Causes of Hypothyroidism

The causes of hypothyroidism can be divided into two branches, primary cause and secondary cause.

A primary cause directly impacts the thyroid gland, resulting in low thyroid hormone production. The most common among these primary causes is an autoimmune condition called Hashimoto’s disease. This is a hereditary condition where the body’s immune system attacks and damages the thyroid gland, thus preventing enough release of thyroid hormone.

While a secondary cause is something where the pituitary gland fails to send thyroid-stimulating hormones to the thyroid gland to balance out thyroid hormone secretion.  

Types of Hypothyroidism

Hypothyroidism can be classified into three types which are as follows:

1. Primary Hypothyroidism is the most common type and is caused by thyroid hormone deficiency. It is also clinically defined by high thyroid-stimulating hormone (TSH) and low free thyroxine (T4) levels.

2. Central Hypothyroidism - It is a rare type and is caused by pituitary or hypothalamus disorders. It is clinically defined by low to normal TSH and low free T4 levels.

3. Peripheral Hypothyroidism is caused by consumptive hypothyroidism due to abnormal expression of the deiodinase 3 enzyme that inactivates thyroid hormone.

The Link Between Diet and Hypothyroidism

Hypothyroidism is often tricky to manage as the food in everyday diet may hamper thyroid treatment. While some nutrients can profoundly influence the function of the thyroid gland, others can inhibit the body’s capacity to absorb the replacement hormones taken as a part of thyroid treatment.

Foods to Eat for Hypothyroidism

A nutritious diet is very important to everyone and studies have often shown that certain dietary interventions benefit people suffering from hypothyroidism. For example, gluten-free, anti-inflammatory, and autoimmune elimination diets benefit patients suffering from Hashimoto’s disease.

List of Nutrient-Rich Foods for Hypothyroidism

For people with hypothyroidism, foods containing the following nutrients are necessary to consume as they can effectively improve thyroid gland activity.

1. Food Containing Iodine - The body needs iodine to synthesize thyroid hormone and a deficiency in this nutrient leads to hypothyroidism. Thus, a diet for hypothyroidism must involve iodine in meals. Foods rich in iodine include :

• Iodised table salt

• Cheese

• Milk

• Seaweeds

• Whole egg

• Saltwater fish

2. Foods Containing Selenium - Selenium is a micronutrient that assists thyroid hormone production and has antioxidant activity. Studies showed that maintaining proper selenium levels in the body can prevent thyroid disease incidence and improve overall health. Foods rich in selenium include:

• Egg

• Beef

• Shrimp

• Tuna

• Brazil nuts

• Ham

• Brown rice

• Chicken

3. Foods Containing Zinc – Zinc also benefits people with low thyroid hormone levels. Studies have shown that zinc alone or combined with selenium may effectively cure hypothyroidism in females. Some foods rich in zinc include:       

• Beef

• Chicken

• Pork

• Pumpkin seeds

• Yogurt

• Crab

• Oysters

• Legumes

Balanced Diet for Hypothyroidism

Generally, a balanced diet for hypothyroidism must include plenty of fruits, vegetables, healthy fats, filling proteins, and a modest amount of healthy carbohydrates. Still, each person may experiment and develop a diet that can suit them the best.

The Role of Protein in Managing Hypothyroidism

Proteins often help to boost thyroid functioning in individuals. A diet low in protein can suppress the thyroid gland leading to hypothyroid-like symptoms. These include cold hands and feet, anxiety, depression, weight gain, fatigue, mental fog, etc.

The Importance of Iodine in the Diet for Hypothyroidism

Iodine is an essential nutrient required to produce thyroid hormones. Lack of sufficient iodine intake is the most prevalent cause of hypothyroidism worldwide. Its deficiency causes a health condition with an enlarged thyroid gland, known as goitre.

However, in spite of its importance in curbing hypothyroidism, it is essential to know that people suffering from this condition should not take iodine supplements unless recommended by a healthcare provider. Excessive consumption can be harmful and, in worse situations, give rise to hyperthyroidism.

Best Sources of Iodine

Iodine is an essential mineral that ensures the proper functioning of the thyroid gland and must be included in the diet. Some of the best iodine sources are :

• Seaweeds

• Cod or Whitefish

• Dairy products like milk

• Iodized salt

• Tuna

• Shrimp

• Prunes or dried plums

• Eggs

Foods to Avoid for Hypothyroidism

Foods containing certain nutrients may interfere with thyroid health and inhibit the absorption of thyroid medication. Thus, restricting the intake of these foods may enable better hypothyroidism management.

List of Foods to Avoid or Limit for Hypothyroidism

People suffering from hypothyroidism must limit the consumption of certain foods, which are listed below:

1. Goitrogens – When consumed in large amounts, these compounds may affect thyroid health. Certain cruciferous vegetables like cauliflower, cabbage, and broccoli contain these compounds; however, cooking them in high flame deactivates their activity.

2. Soy – Few studies have shown that soy products like soy milk, tofu, or soy sauce may interfere with the body’s ability to produce thyroid hormones or absorb thyroid medications. However, other studies showed that soy does not significantly affect thyroid hormones but mildly increased TSH levels.

3. Gluten – People with hypothyroidism must minimise the consumption of food containing gluten, a protein found in food processed from wheat, barley, rice, and other grains. Gluten often irritates the small intestine and hinders the absorption of thyroid hormone replacement medications.

Impact of Processed and Junk Food on Hypothyroidism

Processed foods or junk foods generally have a lot of sodium in them, which must be avoided by people suffering from hypothyroidism. An underactive thyroid increases a person’s risk of developing high blood pressure; too much sodium intake can worsen that.

The Role of Sugar and Carbohydrates in Hypothyroidism

People with hypothyroidism have a slow body metabolism rate and thus quite easy to put on pounds. Excessive consumption of sugar and carbohydrates will just increase calorie intake, which will worsen the weight loss journey. Thus, reducing the amount of sugar intake or completely eliminating it from the diet is recommended.

Lifestyle Changes for Hypothyroidism

Lifestyle changes, including eating certain foods, restricting junk, and regular exercise, can help maintain proper thyroid functioning, although they cannot wholly suffice as a treatment.

Exercise for Hypothyroidism

Exercise can help manage hypothyroidism symptoms, like fatigue and weight gain, although it can’t be a substitute for thyroid replacement medications. However, some exercises such as leg raise and push-ups help build muscle mass, thus burning more calories and boosting health conditions.

Stress Management for Hypothyroidism

Managing stress by doing regular physical activity can boost energy and improve mood swings and fatigue often faced by people suffering from hypothyroidism.

The Impact of Sleep on Hypothyroidism

Several studies suggested that rapid eye movement (REM) sleep deprivation induces central hypothyroidism, reducing TSH release and circulating T4 levels. Thus people with hypothyroidism often face fatigue, lack of energy, and excessive daytime sleepiness. 

Read more about: Thyroid Disorders

Supplementation for Hypothyroidism

People with hypothyroidism must take supplements containing vitamins and nutrients to help them manage hypothyroidism.

The Role of Supplements in Managing Hypothyroidism

Several supplements are beneficial in improving thyroid function and hormone levels. However, the prescribed amount of supplements must be taken. Otherwise, it might lead to adverse outcomes.

The Best Supplements for Hypothyroidism

 Some of the best supplements for hypothyroidism are listed below:

1. Selenium - People with thyroid problems may benefit from taking Selenium.

2. Vitamin D - People with Hashimoto’s disease have Vitamin D deficiency; thus, supplementation is often necessary.  

3. Probiotics - Probiotics are often effective in curbing small intestine bacterial overgrowth (SIBO), often seen in patients with hypothyroidism. In this health condition, bacteria from the colon spread into the small intestine resulting in some expected changes in the intestine.

Conclusion

Hypothyroidism, or an underactive thyroid, is a health condition affecting many people worldwide. It causes many symptoms like fatigue, weight gain, mood swings, and cold intolerance. However, eating the right nutrients and taking proper medications can help lessen the symptoms and improve thyroid gland functioning, resulting in overall well-being.

Frequently Asked Questions

1. What Foods Should I Avoid for Hypothyroidism?

One should avoid having goitrogens, soy products, gluten-rich food, junk and processed food, and sugar-rich food.

2. What Foods Should I Eat for Hypothyroidism?

Food containing iodine, selenium, and zinc, including chicken, tuna, beef, pork, legume, and shrimp, is suitable for hypothyroidism patients.

3. How Does Stress Affect Hypothyroidism?

Under stress, the body releases a hormone called cortisol. This can suppress the functioning of the pituitary gland and prevent the release of thyroid-stimulating hormone, thus inducing hypothyroidism.

4. What Supplements are Beneficial for Hypothyroidism?

Selenium, Vitamin D, and probiotics are beneficial for hypothyroidism.

5. Is There a Specific Diet Plan for Hypothyroidism?

There are no specific thyroid diet plans. However, people with thyroid disease must eat balanced portion-controlled meals. It is important to include fresh fruits and vegetables, whole grains, and legumes which can be beneficial in many ways.

6. What is the role of the Thyroid Gland in the body?

The thyroid gland is a vital hormone that plays a major role in the growth, metabolism, and development of the human body. It regulates diverse body functions by constantly secreting a stable amount of thyroid hormones in the bloodstream.