How To Detect Hypothyroidism in Children and Adolescents

The thyroid is the butterfly-shaped gland that is part of the endocrine system. It is found at the base of the neck and produces hormones that are essential in children for influencing growth and development as well as regulating metabolism, energy, heart function, muscles, and temperature. 

Hypothyroidism is the most common thyroid dysfunction in children and adolescents. It occurs when the thyroid is underactive and does not produce enough thyroid hormones. Since these hormones influence every cell in the body and are crucial for brain development and growth, hypothyroidism can have wide-reaching impacts in children and adolescents, including overall slowing of growth and pubertal onset and disrupted metabolic processes. This can result in short stature, fatigue, weight gain, decreased body temperature, hair thinning, constipation, brain fog, and fluid retention. Hypothyroidism in children has also been shown to affect neurological and psychological development.

If unrecognized and untreated, an under-functioning thyroid gland in a child can have devastating effects, such as stunted physical growth and mental retardation. 

A functional medicine approach to hypothyroidism in children and adolescents aims to uncover potential factors contributing to why the thyroid is under-functioning and helps to support balance.

[signup]

What Does The Thyroid Do?

The thyroid gland is a key player in the endocrine system. It produces and releases thyroid hormones into the blood that travel throughout the body and act on various tissues. The thyroid interacts with other endocrine organs as part of a complex interplay of signals coordinated by the brain and influenced by several nutrients and other hormones. 

The hypothalamus in the brain is responsible for managing hunger, thirst, sleep, hormones, and body temperature and monitors the level of thyroid hormone present in the blood. When it detects the need for increasing metabolism and energy, it releases Thyroid Releasing Hormone (TRH) to signal the pituitary gland at the base of your brain to release Thyroid Stimulating Hormone (TSH). 

TSH acts directly on the thyroid, stimulating it to produce and release thyroid hormones. To do this, the thyroid uses the amino acid tyrosine and iodine to manufacture and convert thyroid hormones, including T4, a storage form of thyroid hormone that circulates throughout the blood and is stored in tissues for when it is needed, and T3, the active form of thyroid hormone.

When different parts of the body need active T3, they convert the storage T4 to active T3 using an enzyme called deiodinase. T3 can then act on cells to stimulate energy production and regulate metabolism.

What Is Hypothyroidism?

Hypothyroidism is when the thyroid does not make enough thyroid hormone to keep the body running normally. In other words, hypothyroidism involves an underactive thyroid gland.

Hypothyroidism can result when the thyroid gland is underactive and not producing enough thyroid hormones, and/or the thyroid hormones cannot work correctly in the peripheral tissues.

This can happen for several reasons. For example, the pituitary gland can malfunction and not send enough Thyroid Stimulating Hormone (TSH) to the thyroid gland. In other cases, TSH levels can be normal, yet the thyroid does not produce enough T4 and T3 to adequately stimulate cells due to nutritional deficiencies, malfunction, or other factors. Another potential way hypothyroidism can develop is if the peripheral receptors do not respond properly to thyroid hormones.

How Common Is Hypothyroidism In Children and Adolescents?

Rates of hypothyroidism in children and adolescents vary around the world. One out of every 4,000 to 5,000 babies in the United States is born with congenital hypothyroidism. Most cases of hypothyroidism in children and adolescents are acquired after birth, with only around 10-15% of cases due to congenital defects of the thyroid gland. 

The most common cause of hypothyroidism in children and adolescents is the autoimmune condition Hashimoto's thyroiditis which occurs in around 1/10,000 of children in the United States to 1/100,000 of children in the UK and Ireland and may be associated with other autoimmune disorders like type 1 diabetes, Addison's disease, and Down syndrome. Like other autoimmune diseases, the prevalence of hypothyroidism due to Hashimoto's thyroiditis appears to be increasing. 

Hypothyroidism Symptoms Found In Children and Adolescents

When the thyroid does not produce enough hormones or the hormones it produces can not act effectively, cells throughout the body are impacted. In children and adolescents, hypothyroidism can result in slowed growth, impaired height increases, and delayed pubertal development. Other specific symptoms of hypothyroidism can vary depending on the age and developmental stage of the child. 

Overall, hypothyroidism in children and adolescents can also cause symptoms throughout the body, such as:

• Fatigue 
• Mild weight gain despite decreased appetite
• Headaches and migraines
• Thinning or dry hair, nails, and skin
• Brittle nails
• Feeling cold all the time and decreased body temperature
• Puffiness or fluid retention
• Slowed heart rate
• Slow digestion and constipation
• Depression 
• Aching muscles and joints
• Loss of muscle strength and tone
  

In young children, like toddlers and elementary school children, hypothyroidism can cause:

• Shorter than average height
• Delayed eruption of permanent teeth
• Shorter than average limb length
• Slowed mental development
  

Teenagers and adolescents with hypothyroidism may experience particular symptoms, such as:

• Slowed growth
• Looking younger than their age
• Delayed puberty 
• Increased testicular size in boys
• Missing or delayed start to menstruation
• Heavy or irregular menstrual bleeding
• Changes in behavior and difficulties with school performance and concentration
  

Over time, untreated hypothyroidism can lead to additional bodywide complications, including:

• Elevated cholesterol
• Heart disease and heart failure
• High blood pressure 
• Myxedema a rare, life-threatening condition where the body's functions slow down significantly

Possible Causes of Hypothyroidism In Children and Adolescents

Sometimes, a child is born with an absent or underactive thyroid gland, a condition known as congenital hypothyroidism, while in other cases, the thyroid gland stops functioning normally later on after birth, a condition known as 'acquired' hypothyroidism. Some of the most common causes of acquired hypothyroidism in children and adolescents include the autoimmune disease Hashimoto's thyroiditis, inflammatory thyroiditis, environmental factors, surgical removal of the thyroid gland, radiation damage to the gland, medication impacts, iodine imbalance, and pituitary gland dysfunction.

Hashimoto's Thyroiditis

Hashimoto's disease is the most common cause of hypothyroidism in children and adolescents (as well as in adults) in iodine-sufficient areas of the world like the US. In this autoimmune condition, the body produces antibodies that attack and damage the thyroid gland, causing inflammation and impairing the thyroid's ability to produce thyroid hormone over time. Children usually develop this form of acquired hypothyroidism after the first few years of life.

Some of the main factors that can contribute to autoimmunity and the development of Hashimoto's disease include imbalances in gut health, nutrition, infections, environmental exposures, and genetics.

Inflammatory Thyroiditis

In addition to Hashimoto's, inflammatory thyroiditis can result from a viral or bacterial infection or due to certain medications like interferon and amiodarone that can damage thyroid cells.

Environmental Factors

Environmental factors such as heavy metals and endocrine-disrupting chemicals (EDCs) found in foods, food packaging, water, and personal care products, can interfere with thyroid gland functioning and thyroid hormone transport through multiple mechanisms. Past or ongoing exposures to heavy metals, mercury, arsenic, cadmium, solvents, plastics, and pesticides contribute to imbalanced gut bacteria (dysbiosis), inflammation, and autoimmunity by harming the body's detoxification, digestive, nervous, and endocrine systems. Certain chemicals such as fluoride and bromine in municipal water supplies, flame retardants, and some baked goods can directly compete with iodine in the thyroid gland, impacting its functioning. 

Iodine Deficiency 

Iodine is a trace mineral found in seafood, seaweed, plants grown in iodine-rich soil, and iodized salt and is needed for the production of thyroid hormones. Too little iodine can lead to hypothyroidism since the gland cannot adequately produce T3 and T4, while too much iodine can worsen hypothyroidism in children with the condition.

Surgery, Radiation, and Other Treatments

Radioactive iodine or anti-thyroid medications are often used to manage hyperthyroidism when too much thyroid hormone is produced. If hyperthyroidism is over-corrected, it can lower thyroid hormone production too much, resulting in permanent hypothyroidism. 

Removing all or a significant portion of the thyroid gland via surgery or damaging it via radiation treatments can lead to hypothyroidism. ‍

Radiation used for treating hyperthyroidism or other conditions in the neck can injure the thyroid and impact its function.

Certain Medications

Several other medications can also contribute to hypothyroidism. These include lithium which may be used to manage mental health disorders like bipolar affective disorder, amiodarone which is used to manage abnormal heart rhythms, and certain medications that help to regulate the immune system and manage infections like HIV and hepatitis. 

Pituitary Disorders

A failure of the pituitary gland to produce enough thyroid-stimulating hormone (TSH) results in the thyroid gland failing to produce enough thyroid hormones. This usually occurs due to a benign pituitary gland tumor, inflammation of the pituitary gland, or elevated pressure in the brain that compresses and dysregulates the pituitary gland.

Functional Medicine Labs to Test for Root Cause of Hypothyroidism In Children and Adolescents

Functional medicine testing can help identify potential underlying factors contributing to hypothyroidism in children and adolescents. This includes assessing the functioning of the thyroid, measuring thyroid-supporting nutrients, and evaluating factors that play a role in immune system function to uncover the causes of the autoimmunity leading to Hashimoto's disease when that is the cause. 

Thyroid Function And Autoantibodies

A Complete Thyroid Panel by ZRT is beneficial for pediatric patients as it can easily be done at home via blood stick and urine testing to assess the state of a child's or adolescent's thyroid function. This test includes thyroid-stimulating hormone (TSH), T3 (free and total), T4 (free and total), and reverse T3. It also tests if an individual has too little or too much iodine and selenium and/or exposure to the iodine/selenium antagonists - bromine, arsenic, and mercury.

Practitioners will assess and review these results using functional medicine ranges. Compared to conventional lab ranges, which are based on results from the overall population, functional medicine thyroid lab ranges are tailored to detect thyroid issues prior to the onset of more advanced thyroid disease. 

TSH measures how the pituitary gland in the brain communicates with the thyroid and indicates hypothyroidism in a child or adolescent when elevated. A normal TSH does not rule out thyroid issues on its own since it is an indirect but specific measure of thyroid function. 

Free T4 measures the bioavailable or unbound thyroid hormone and is a marker of low thyroid function when decreased.

In the peripheral tissues, T4 is converted to T3. A low level of T3 can indicate low thyroid function in a child or adolescent or a problem with conversion, which often occurs with chronic stress, inflammation, or a high toxic burden. 

Some T4 is also converted to reverse T3, which serves as a "brake" since it competes with free T3 for cell receptor sites. High levels of reverse T3 can cause hypothyroidism and usually reflects a systemic issue like chronic inflammation.

In addition, thyroid antibody testing for thyroid peroxidase (TPO) and anti-thyroglobulin (TG) antibodies are key for diagnosing Hashimoto's disease as the cause of hypothyroidism in children and adolescents. In addition to elevated TPO antibodies which are typically found in Hashimoto's disease, thyroglobulin antibodies may also be elevated. However, these antibodies are usually associated with Grave's disease or autoimmune hyperthyroidism.

These thyroid hormone levels should generally be checked 4 to 8 weeks after starting thyroid hormone medication or after any change in medication dose. As children get older, levels are usually reviewed every 3-12 months until they have finished growing and going through puberty, after which they should be monitored at least once a year.

Thyroid Supportive Nutrients 

Nutrients including iodine, iron, tyrosine, zinc, selenium, magnesium, and vitamins E, B2, B3, B6, C, and D all contribute to the proper production of thyroid hormones, and some of these, including zinc and selenium, are also important for supporting the conversion of T4 to T3. Other nutrients like vitamin A improve cellular sensitivity to thyroid hormones.

Micronutrient testing analyzes vitamins, minerals, and other nutrients along with these micronutrients' performance and functional deficiencies. Based on these results, practitioners individualize supplement protocols as necessary. 

Gut Health

Since dysbiosis and leaky gut are critical factors in developing autoimmunity like Hashimoto's disease and overall inflammation that can impact the thyroid, assessing gut health can help provide targeted interventions. A Comprehensive Stool Test measures amounts of healthy and unbalanced gut bacteria (dysbiosis), inflammatory markers, leaky gut, parasites, and yeast to assess the state of the gut and guide treatment aimed at restoring balance. 

Additional testing for gluten sensitivity or celiac disease with an evaluation of the leaky gut marker zonulin can also help to guide treatment.

Food sensitivities can contribute to increased intestinal permeability, inflammation, and autoimmunity. Food sensitivity testing can be done at home via blood spot which is beneficial for pediatric testing. 

Other Factors That Influence Detoxification

Methylation, detoxification capacity, and glutathione (tested on micronutrient testing) production can be assessed with specialized labs to understand an individual's genetic susceptibilities and current detoxification capacity. This helps pinpoint areas that can be supported to bring the body and metabolism back into balance. 

[signup]

Conventional Hypothyroidism Treatment For Children and Adolescents

Conventional treatment for overt hypothyroidism in children and adolescents focuses on replacing the thyroid hormones with medication like levothyroxine (T4 only) that the child's thyroid gland is no longer making sufficiently for itself. While conventional treatment of hypothyroidism usually relies on thyroid medication, it alone does not address the underlying condition but rather the symptoms resulting from low thyroid hormones. 

Functional Medicine Treatment for Hypothyroidism in Children and Adolescents

A functional medicine approach to managing hypothyroidism aims to address identified underlying factors contributing to the imbalance. For example, strategies can be used to support and regulate the immune system in cases of Hashimoto's thyroiditis and not simply only replace thyroid hormone. An individualized treatment approach guided by clinical symptoms and functional laboratory testing can tailor a dietary and lifestyle approach that works for each child.

It is important to figure out the contributing root causes, such as addressing gut imbalances, toxicant exposures, systemic inflammation, and chronic stress, and avoid any individual triggers. Utilizing lifestyle and functional medicine approaches to address root causes can also support the health of the thyroid gland.

Hypothyroidism Diet for Children and Adolescents

An essential step in dealing with thyroid imbalances in children and adolescents is to eliminate contributing factors to the dysfunction, such as an imbalanced diet, nutrient deficiencies, and chronic stress from a poor diet that leads to hormonal changes. Inflammation can negatively impact thyroid function and increase the chance of an autoimmune reaction that can affect the thyroid gland, so a nutrient-rich, anti-inflammatory diet tailored to an individual child's sensitivities and needs can help balance inflammation and support immune health. Eliminating unique trigger foods, such as gluten and other grains, dairy, processed sugars, and other foods that an individual is sensitive to helps to calm systemic inflammation. 

Rebalance the Gut Microbiome

Since the gut microbiome has such a significant impact on the immune system, maintaining diverse and balanced bacteria in the gut can help support immune health. Restoring equilibrium in the gut microbiota by feeding children a variety of whole foods and incorporating probiotic-rich foods like kimchi and sauerkraut that contain naturally-occurring probiotics and prebiotic-rich foods like artichokes, garlic, and beans that nourish healthy bacteria is critical for supporting the mucosal barrier and managing inflammation and immune responses that can affect thyroid function. 

Restore Thyroid-Supporting Nutrients

In children who show nutrient deficiencies, balancing the intake of micronutrients like vitamin A, zinc, vitamin D, omega-3 fatty acids, and selenium can help to support overall health and thyroid function. 

While iodine is a mineral that the thyroid uses to make thyroid hormones, too high iodine intake can come from too much salt in the form of processed, packaged foods, or excessive consumption of seaweeds, for example, can negatively affect thyroid functioning. Functional laboratory testing can help guide individualized intake.

Supplements and Herbs For Hypothyroidism in Children and Adolescents

Supplementation with the adaptogen ashwagandha has been used to help address thyroid dysfunctions in adults, although studies are lacking looking at this supplement in children and adolescents with hypothyroidism. 

Adequate Sleep and Stress Management 

High levels of chronic stress contribute to hypothyroidism and inflammation and have been associated with autoimmunity. Finding balance via lifestyle practices like adequate quality sleep and balanced movement can improve thyroid and overall health for children and adolescents. 

Restorative exercises such as yoga, swimming, and walking are generally more helpful for managing inflammation than overly intense exercise. Spending calm time in nature can also support well-being by providing exposure to natural sunlight to optimize vitamin D and direct contact with the earth.

Addressing Environmental Factors

Chemicals in plastics, pesticides, heavy metals, and other pollutants can disrupt thyroid function. You can reduce your child's exposure to these chemicals by using high-quality water and air filters, choosing organic produce, and assessing other exposures, such as metal dental amalgams. 

[signup]

Summary

Hypothyroidism in children and adolescents occurs when the child's thyroid gland does not produce enough thyroid hormones or the hormones are blocked from working effectively. This leads to a cascade of symptoms throughout the body, like impaired growth and development, fatigue, increased sensitivity to cold, constipation, and hair loss. The autoimmune disease Hashimoto's thyroiditis is the most common cause of hypothyroidism in children and adolescents. 

A comprehensive thyroid panel including TSH, free T4, free T3, reverse T3, and thyroglobulin antibodies can provide a picture of a child’s overall thyroid function. In addition to TSH, which is conventionally used to screen for thyroid function, assessing for the presence of TPO antibodies in the blood against the thyroid gland helps to diagnose Hashimoto’s thyroiditis. A functional medicine approach can also look at other markers of autoimmunity and systemic inflammation by assessing thyroid-supportive nutrients, markers of gut health and food sensitivities, and a child’s detoxification function.

Since hypothyroidism in children and adolescents can impact the entire body and result from various causes, a functional medicine approach identifies and addresses underlying factors that may contribute to inflammation and autoimmunity to support the thyroid as well as the immune system. Identifying and addressing these factors can help support a child's normal growth and development.