thyroid and dhea

Thyroid and DHEA: Unraveling the Connection

Key Takeaways

  • Balancing DHEA Levels: Understanding the role of DHEA in thyroid function and mean DHEAS can help individuals take actionable steps to balance their DHEA levels through lifestyle changes and, if necessary, medical intervention.

  • Recognizing the symptoms of DHEA imbalance linked to thyroid issues and mean DHEAS can prompt individuals to seek timely medical evaluation and treatment for potential thyroid-related concerns.

  • Informed Decision-Making: Research insights on DHEA and thyroid autoimmunity, mean DHEAS, provide valuable information for individuals to make informed decisions about incorporating oral dehydroepiandrosterone supplements into their thyroid health management.

  • Considerations for Use: Evaluating the benefits of DHEA for thyroid health, estrogen, and high levels requires careful consideration of potential side effects and individual health circumstances, empowering readers to make informed choices about DHEA use.

  • Comprehensive Health Management: Understanding DHEA’s role in bone density and depression for thyroid patients highlights the importance of a comprehensive approach to managing thyroid conditions, including considerations beyond hormone levels.

  • Exploring 7-Keto DHEA: The impact of 7-Keto DHEA on thyroid disorders and its potential benefits underscores the need for individuals to discuss specific DHEA supplements with their healthcare providers to determine suitability and potential benefits.

Studying how the thyroid and DHEA levels affect our health can help us understand how they control our energy, hormones, and immune system. Knowing this can help us manage tiredness, weight changes, and hormone problems. Learning about this connection can show us how to improve our health by treating thyroid function, DHEA levels, and vitamins in a targeted way.

Understanding the Role of DHEA in Thyroid Function

Supporting Thyroid Hormone Production

DHEA, a hormone produced by the adrenal glands, plays a crucial role in thyroid function. It supports the production of thyroid hormones essential for regulating metabolism and various bodily functions. Without adequate DHEA levels and vitamins, the thyroid may struggle to produce sufficient hormones, leading to potential imbalances and health issues.

DHEA contributes to maintaining optimal hormone levels within the body. By aiding in thyroid hormone production and vitamins, metabolic processes run smoothly and efficiently. This means that individuals with healthy DHEA levels and vitamin intake are more likely to have balanced thyroid hormone levels, supporting overall well-being and vitality.

Regulating Metabolism and Overall Health

DHEA helps make thyroid hormones and keeps your metabolism working well. This is important for having energy, managing weight, and staying healthy. DHEA helps your body use energy better and keeps your thyroid and vitamins in check so you can stay at a healthy weight and have energy all day.

Furthermore, DHEA’s contribution to overall thyroid health extends beyond metabolism regulation. It ensures the thyroid gland functions optimally, promoting general well-being and vitality by providing essential vitamins. When DHEA levels are balanced and adequate, individuals are more likely to experience improved energy levels, mental clarity, and overall physical wellness.

Symptoms of DHEA Imbalance Linked to Thyroid Issues

Fatigue and Weakness

thyroid and dhea

Feeling constantly tired and weak might indicate an imbalance in DHEA levels, especially when associated with thyroid issues. When the body’s production of DHEA is disrupted, it can lead to persistent fatigue and weakness. For instance, individuals with low levels of DHEA may experience prolonged exhaustion despite getting enough rest.

Hair Loss and Dry Skin An imbalance in DHEA levels linked to thyroid problems could manifest as hair loss and dry skin. The skin may become excessively dry or flaky, while hair loss might occur more than usual. These clinical features often indicate the need for further investigation into potential hormonal imbalances.

Mood Swings and Irritability Unexplained mood swings or heightened irritability may signal an underlying issue related to DHEA levels affected by thyroid problems. Individuals experiencing frequent changes in mood without a clear cause should consider consulting a healthcare professional to explore potential hormonal irregularities.

In some cases, joint pains can also be linked to imbalanced DHEA levels influenced by thyroid issues. It’s essential for individuals experiencing these symptoms alongside known or suspected thyroid complications to seek medical advice promptly.

Research Insights on DHEA and Thyroid Autoimmunity

Correlation Studies

Recent studies have delved into the potential impact of DHEA levels on thyroid autoimmunity. The correlation between DHEA and autoimmune thyroid conditions is a subject of increasing interest among researchers. These studies explore how variations in DHEA levels may influence the development and progression of thyroid autoimmunity.

Scientists have found that DHEA might help with thyroid problems. Keeping DHEA levels right could be important for dealing with thyroid autoimmunity.

The data from these studies also provide valuable insights into how changes in DHEA levels may affect the overall activity of the thyroid axis, shedding light on potential mechanisms underlying autoimmune processes within the thyroid gland.

Animal Studies

In addition to human-based research, animal studies involving rats have contributed significant findings. By examining various parameters such as CSA score (a measure related to tissue damage), these animal studies have provided essential data supporting the connection between DHEA, immune response modulation, and its potential implications for autoimmune conditions affecting the thyroid.

Furthermore, several recent publications with unique PMIDs have presented compelling evidence about how fluctuations in DHEA levels can influence different facets of immune responses associated with disorders like Hashimoto’s disease or Graves’ disease.

Evaluating the Benefits of DHEA for Thyroid Health

Supporting Thyroid Function

DHEA supplementation may help support thyroid function in some cases. Studies suggest that balancing DHEA levels could alleviate certain thyroid disorder symptoms. For example, individuals with low DHEA and high cortisol levels might experience improved thyroid function through DHEA supplementation.

Research has shown that mean DHEAS (dehydroepiandrosterone sulfate) levels are significantly lower in patients with hypothyroidism compared to healthy individuals. This indicates a potential link between DHEAS and thyroid health, prompting further investigation into the benefits of DHEA for managing thyroid conditions.

Studying Further Benefits

The potential benefits of DHEA for thyroid health are currently being studied further to understand its role in supporting overall well-being. As researchers delve deeper into the relationship between hormone levels and thyroid function, they aim to uncover how optimizing DHEA alongside other hormones, such as testosterone, can positively impact individuals dealing with various thyroid issues.

Ongoing research seeks to determine whether regulating testosterone levels and maintaining balanced DHEAS concentrations can contribute to improved outcomes for those experiencing disruptions in their thyroid function. These studies provide valuable insights and pave the way for alternative or complementary approaches to managing thyroid-related concerns.

Side Effects and Considerations for DHEA Use in Thyroid Conditions

Potential Side Effects

DHEA supplementation may lead to side effects that need careful consideration, especially when used for thyroid conditions. These side effects can include acne, hair loss, stomach upset, high blood pressure, and changes in the menstrual cycle. It’s essential to be aware of these potential outcomes before starting DHEA.

See also
What is Aletris: Overview, Uses, Benefits & More

DHEA is a hormone that can interact with the body in various ways. When used for thyroid conditions, it’s crucial to understand how it might affect the body’s natural balance. Consulting with a healthcare professional is vital before initiating DHEA use. They can provide personalized guidance based on individual health status and needs.

Individual Responses

It’s important to recognize that individual responses to DHEA supplementation can vary significantly. What works well for one person may not have the same effect on another individual with similar conditions. This underscores the necessity of seeking professional advice tailored to personal circumstances before using DHEA for thyroid health.

DHEA has been associated with both positive and negative outcomes depending on an individual’s unique physiology and existing medical issues such as thyroid conditions. Understanding these variations can help individuals make informed decisions about whether or not to incorporate DHEA into their management plan.

DHEA’s Role in Bone Density and Depression for Thyroid Patients

Maintaining Bone Density

thyroid and dhea

Research shows that DHEA might help keep **bones strong** for people with thyroid problems. Thyroid issues can mess with hormone balance in the body. This disruption might decrease bone density, making them more susceptible to fractures and osteoporosis. Studies on rats have shown that DHEA supplementation can prevent bone loss caused by thyroid hormone deficiency.

Individuals with thyroid problems must ensure they get enough vitamin D and calcium through their diet or supplements. These nutrients work synergistically with DHEA to support bone health.

Link with Depression

People are looking into how DHEA levels might be connected to depression in people with thyroid problems. Some studies suggest that low DHEA levels could raise the risk of depression in these patients. We still need more research to understand this, but it shows that we should think about hormones and mental health when treating thyroid issues.

Furthermore, maintaining a healthy weight through proper nutrition and regular exercise can positively impact hormone levels and mood for individuals with thyroid issues.

The Impact of 7-Keto DHEA on Thyroid Disorders

Research Findings

Studies are currently investigating the potential influence of 7-Keto DHEA on thyroid disorders. Preliminary research suggests that 7-Keto DHEA may have implications for thyroid health. Researchers are exploring how this compound affects various thyroid disorders, such as hypothyroidism and hyperthyroidism.

The specific effects of 7-Keto DHEA on these different types of thyroid disorders are still under investigation. Some studies indicate that 7-Keto DHEA might play a role in modulating the function of the thyroid gland, potentially impacting hormone levels and overall thyroid health.

Preliminary findings suggest that 7-Keto DHEA could have promising implications for individuals with thyroid disorders, although further research is needed to fully understand its potential benefits and any associated risks.

Dehydroepiandrosterone’s Influence on Autoimmune Hypothyroidism

Research Studies

Scientists have been looking at how a hormone called oral dehydroepiandrosterone is connected to autoimmune hypothyroidism. They want to know if this hormone worsens the condition or causes it.

Studies have also focused on understanding the impact of subclinical hypothyroidism and early rheumatoid arthritis (RA) concerning dehydroepiandrosterone levels. This investigation aims to uncover any potential connections between these conditions and the levels of this steroid hormone.

Importance of Understanding

It’s super important to know how dehydroepiandrosterone affects autoimmune hypothyroidism so we can figure out better ways to treat it. Understanding this can help us manage the condition better and help people have better results. Knowing how this hormone works with the thyroid gland can help us find ways to prevent autoimmune hypothyroidism in people who might be at risk.

Moreover, research exploring the association between adrenal glands’ function and their effect on thyroid health has significant implications for patients with autoimmune hypothyroidism. By understanding these interactions more deeply, healthcare professionals can offer more targeted interventions tailored to each patient’s needs.

Exploring DHEA’s Relationship with Hypothyroidism and Autoimmunity

Research Findings

Research has looked at how DHEA levels might be linked to hypothyroidism, especially in people with autoimmune conditions. The thyroid helps control how our bodies use energy, so figuring out how DHEA fits into this is important. Some studies suggest that having low DHEA levels could raise the chances of getting hypothyroidism, especially the kind caused by the immune system attacking the thyroid.

Some studies show that it’s important to understand how hypothyroidism, autoimmunity, and DHEA are connected. In one study, people with low levels of DHEA were more likely to get autoimmune diseases like rheumatoid arthritis. This shows how DHEA levels can affect thyroid function and the immune system.

Implications for Treatment

Understanding the interplay between thyroid, autoimmunity, and DHEA is crucial for developing effective treatment strategies. By recognizing the potential influence of DHEA on autoimmune hypothyroid conditions, healthcare professionals can explore targeted interventions to address both hormone imbalances and immune dysregulation simultaneously.

Furthermore, these findings open up avenues for personalized medicine tailored to individual differences in hormone levels. For instance, considering age-related changes in hormone production is vital when designing treatment plans for people at different stages of life.

Final Remarks

You learned about how DHEA can affect your thyroid and your health. Knowing this can help you make better choices for your thyroid. You also learned about the good things DHEA can do for your bones and mental health. When taking care of your thyroid, you must talk to your doctor for advice that fits you.

Keep seeking knowledge and taking proactive steps to support your thyroid health. Stay curious, stay informed, and stay empowered in your pursuit of overall well-being.

Frequently Asked Questions

What is the role of DHEA in thyroid function?

DHEA supports thyroid function by influencing metabolism, immune response, and hormone production. It also aids in regulating stress levels and promoting overall well-being.

Are there any common symptoms of DHEA imbalance linked to thyroid issues?

Symptoms can include fatigue, weight changes, mood swings, and hair loss. These imbalances may also contribute to fluctuations in energy levels and affect overall vitality.

Can DHEA benefit thyroid health?

Research suggests that DHEA supplementation may benefit individuals with thyroid conditions by potentially improving hormone balance and supporting bone density.

What are some side effects or considerations for using DHEA in thyroid conditions?

Possible side effects include acne, hair loss, and changes in blood sugar levels. It’s important to consult with a healthcare professional before starting any new supplement regimen.

How does 7-Keto DHEA impact thyroid disorders?

7-Keto DHEA has been studied for its potential to support healthy metabolism without affecting the body’s hormonal balance. Research indicates it may have positive effects on individuals with thyroid disorders.DHEA supplementation may lead to2>

  • Balancing DHEA Levels: Understanding the role of DHEA in thyroid function and mean DHEAS can help individuals take actionable steps to balance their DHEA levels through lifestyle changes and, if necessary, medical intervention.

  • Recognizing the symptoms of DHEA imbalance linked to thyroid issues and mean DHEAS can prompt individuals to seek timely medical evaluation and treatment for potential thyroid-related concerns.

  • Informed Decision-Making: Research insights on DHEA and thyroid autoimmunity, mean DHEAS, provide valuable information for individuals to make informed decisions about incorporating oral dehydroepiandrosterone supplements into their thyroid health management.

  • Considerations for Use: Evaluating the benefits of DHEA for thyroid health, estrogen, and high levels requires careful consideration of potential side effects and individual health circumstances, empowering readers to make informed choices about DHEA use.

  • Comprehensive Health Management: Understanding DHEA’s role in bone density and depression for thyroid patients highlights the importance of a comprehensive approach to managing thyroid conditions, including considerations beyond hormone levels.

  • Exploring 7-Keto DHEA: The impact of 7-Keto DHEA on thyroid disorders and its potential benefits underscores the need for individuals to discuss specific DHEA supplements with their healthcare providers to determine suitability and potential benefits.

See also
The Connection Between Quercetin and Heart Disease

Studying how the thyroid and DHEA levels affect our health can help us understand how they control our energy, hormones, and immune system. Knowing this can help us manage tiredness, weight changes, and hormone problems. Learning about this connection can show us how to improve our health by treating thyroid function, DHEA levels, and vitamins in a targeted way.

Understanding the Role of DHEA in Thyroid Function

Supporting Thyroid Hormone Production

DHEA, a hormone produced by the adrenal glands, plays a crucial role in thyroid function. It supports the production of thyroid hormones essential for regulating metabolism and various bodily functions. Without adequate DHEA levels and vitamins, the thyroid may struggle to produce sufficient hormones, leading to potential imbalances and health issues.

DHEA contributes to maintaining optimal hormone levels within the body. By aiding in thyroid hormone production and vitamins, metabolic processes run smoothly and efficiently. This means that individuals with healthy DHEA levels and vitamin intake are more likely to have balanced thyroid hormone levels, supporting overall well-being and vitality.

Regulating Metabolism and Overall Health

DHEA helps make thyroid hormones and keeps your metabolism working well. This is important for having energy, managing weight, and staying healthy. DHEA helps your body use energy better and keeps your thyroid and vitamins in check so you can stay at a healthy weight and have energy all day.

Furthermore, DHEA’s contribution to overall thyroid health extends beyond metabolism regulation. It ensures the thyroid gland functions optimally, promoting general well-being and vitality by providing essential vitamins. When DHEA levels are balanced and adequate, individuals are more likely to experience improved energy levels, mental clarity, and overall physical wellness.

Symptoms of DHEA Imbalance Linked to Thyroid Issues

Fatigue and Weakness

thyroid and dhea

Feeling constantly tired and weak might indicate an imbalance in DHEA levels, especially when associated with thyroid issues. When the body’s production of DHEA is disrupted, it can lead to persistent fatigue and weakness. For instance, individuals with low levels of DHEA may experience prolonged exhaustion despite getting enough rest.

Hair Loss and Dry Skin An imbalance in DHEA levels linked to thyroid problems could manifest as hair loss and dry skin. The skin may become excessively dry or flaky, while hair loss might occur more than usual. These clinical features often indicate the need for further investigation into potential hormonal imbalances.

Mood Swings and Irritability Unexplained mood swings or heightened irritability may signal an underlying issue related to DHEA levels affected by thyroid problems. Individuals experiencing frequent changes in mood without a clear cause should consider consulting a healthcare professional to explore potential hormonal irregularities.

In some cases, joint pains can also be linked to imbalanced DHEA levels influenced by thyroid issues. It’s essential for individuals experiencing these symptoms alongside known or suspected thyroid complications to seek medical advice promptly.

Research Insights on DHEA and Thyroid Autoimmunity

Correlation Studies

Recent studies have delved into the potential impact of DHEA levels on thyroid autoimmunity. The correlation between DHEA and autoimmune thyroid conditions is a subject of increasing interest among researchers. These studies explore how variations in DHEA levels may influence the development and progression of thyroid autoimmunity.

Scientists have found that DHEA might help with thyroid problems. Keeping DHEA levels right could be important for dealing with thyroid autoimmunity.

The data from these studies also provide valuable insights into how changes in DHEA levels may affect the overall activity of the thyroid axis, shedding light on potential mechanisms underlying autoimmune processes within the thyroid gland.

Animal Studies

In addition to human-based research, animal studies involving rats have contributed significant findings. By examining various parameters such as CSA score (a measure related to tissue damage), these animal studies have provided essential data supporting the connection between DHEA, immune response modulation, and its potential implications for autoimmune conditions affecting the thyroid.

Furthermore, several recent publications with unique PMIDs have presented compelling evidence about how fluctuations in DHEA levels can influence different facets of immune responses associated with disorders like Hashimoto’s disease or Graves’ disease.

Evaluating the Benefits of DHEA for Thyroid Health

Supporting Thyroid Function

DHEA supplementation may help support thyroid function in some cases. Studies suggest that balancing DHEA levels could alleviate certain thyroid disorder symptoms. For example, individuals with low DHEA and high cortisol levels might experience improved thyroid function through DHEA supplementation.

Research has shown that mean DHEAS (dehydroepiandrosterone sulfate) levels are significantly lower in patients with hypothyroidism compared to healthy individuals. This indicates a potential link between DHEAS and thyroid health, prompting further investigation into the benefits of DHEA for managing thyroid conditions.

Studying Further Benefits

The potential benefits of DHEA for thyroid health are currently being studied further to understand its role in supporting overall well-being. As researchers delve deeper into the relationship between hormone levels and thyroid function, they aim to uncover how optimizing DHEA alongside other hormones, such as testosterone, can positively impact individuals dealing with various thyroid issues.

Ongoing research seeks to determine whether regulating testosterone levels and maintaining balanced DHEAS concentrations can contribute to improved outcomes for those experiencing disruptions in their thyroid function. These studies provide valuable insights and pave the way for alternative or complementary approaches to managing thyroid-related concerns.

Side Effects and Considerations for DHEA Use in Thyroid Conditions

Potential Side Effects

DHEA supplementation may lead to side effects that need careful consideration, especially when used for thyroid conditions. These side effects can include acne, hair loss, stomach upset, high blood pressure, and changes in the menstrual cycle. It’s essential to be aware of these potential outcomes before starting DHEA.

See also
Supercharge Your Gym Routine with L-Arginine For Workouts!

DHEA is a hormone that can interact with the body in various ways. When used for thyroid conditions, it’s crucial to understand how it might affect the body’s natural balance. Consulting with a healthcare professional is vital before initiating DHEA use. They can provide personalized guidance based on individual health status and needs.

Individual Responses

It’s important to recognize that individual responses to DHEA supplementation can vary significantly. What works well for one person may not have the same effect on another individual with similar conditions. This underscores the necessity of seeking professional advice tailored to personal circumstances before using DHEA for thyroid health.

DHEA has been associated with both positive and negative outcomes depending on an individual’s unique physiology and existing medical issues such as thyroid conditions. Understanding these variations can help individuals make informed decisions about whether or not to incorporate DHEA into their management plan.

DHEA’s Role in Bone Density and Depression for Thyroid Patients

Maintaining Bone Density

thyroid and dhea

Research shows that DHEA might help keep **bones strong** for people with thyroid problems. Thyroid issues can mess with hormone balance in the body. This disruption might decrease bone density, making them more susceptible to fractures and osteoporosis. Studies on rats have shown that DHEA supplementation can prevent bone loss caused by thyroid hormone deficiency.

Individuals with thyroid problems must ensure they get enough vitamin D and calcium through their diet or supplements. These nutrients work synergistically with DHEA to support bone health.

Link with Depression

People are looking into how DHEA levels might be connected to depression in people with thyroid problems. Some studies suggest that low DHEA levels could raise the risk of depression in these patients. We still need more research to understand this, but it shows that we should think about hormones and mental health when treating thyroid issues.

Furthermore, maintaining a healthy weight through proper nutrition and regular exercise can positively impact hormone levels and mood for individuals with thyroid issues.

The Impact of 7-Keto DHEA on Thyroid Disorders

Research Findings

Studies are currently investigating the potential influence of 7-Keto DHEA on thyroid disorders. Preliminary research suggests that 7-Keto DHEA may have implications for thyroid health. Researchers are exploring how this compound affects various thyroid disorders, such as hypothyroidism and hyperthyroidism.

The specific effects of 7-Keto DHEA on these different types of thyroid disorders are still under investigation. Some studies indicate that 7-Keto DHEA might play a role in modulating the function of the thyroid gland, potentially impacting hormone levels and overall thyroid health.

Preliminary findings suggest that 7-Keto DHEA could have promising implications for individuals with thyroid disorders, although further research is needed to fully understand its potential benefits and any associated risks.

Dehydroepiandrosterone’s Influence on Autoimmune Hypothyroidism

Research Studies

Scientists have been looking at how a hormone called oral dehydroepiandrosterone is connected to autoimmune hypothyroidism. They want to know if this hormone worsens the condition or causes it.

Studies have also focused on understanding the impact of subclinical hypothyroidism and early rheumatoid arthritis (RA) concerning dehydroepiandrosterone levels. This investigation aims to uncover any potential connections between these conditions and the levels of this steroid hormone.

Importance of Understanding

It’s super important to know how dehydroepiandrosterone affects autoimmune hypothyroidism so we can figure out better ways to treat it. Understanding this can help us manage the condition better and help people have better results. Knowing how this hormone works with the thyroid gland can help us find ways to prevent autoimmune hypothyroidism in people who might be at risk.

Moreover, research exploring the association between adrenal glands’ function and their effect on thyroid health has significant implications for patients with autoimmune hypothyroidism. By understanding these interactions more deeply, healthcare professionals can offer more targeted interventions tailored to each patient’s needs.

Exploring DHEA’s Relationship with Hypothyroidism and Autoimmunity

Research Findings

Research has looked at how DHEA levels might be linked to hypothyroidism, especially in people with autoimmune conditions. The thyroid helps control how our bodies use energy, so figuring out how DHEA fits into this is important. Some studies suggest that having low DHEA levels could raise the chances of getting hypothyroidism, especially the kind caused by the immune system attacking the thyroid.

Some studies show that it’s important to understand how hypothyroidism, autoimmunity, and DHEA are connected. In one study, people with low levels of DHEA were more likely to get autoimmune diseases like rheumatoid arthritis. This shows how DHEA levels can affect thyroid function and the immune system.

Implications for Treatment

Understanding the interplay between thyroid, autoimmunity, and DHEA is crucial for developing effective treatment strategies. By recognizing the potential influence of DHEA on autoimmune hypothyroid conditions, healthcare professionals can explore targeted interventions to address both hormone imbalances and immune dysregulation simultaneously.

Furthermore, these findings open up avenues for personalized medicine tailored to individual differences in hormone levels. For instance, considering age-related changes in hormone production is vital when designing treatment plans for people at different stages of life.

Final Remarks

You learned about how DHEA can affect your thyroid and your health. Knowing this can help you make better choices for your thyroid. You also learned about the good things DHEA can do for your bones and mental health. When taking care of your thyroid, you must talk to your doctor for advice that fits you.

Keep seeking knowledge and taking proactive steps to support your thyroid health. Stay curious, stay informed, and stay empowered in your pursuit of overall well-being.

Frequently Asked Questions

What is the role of DHEA in thyroid function?

DHEA supports thyroid function by influencing metabolism, immune response, and hormone production. It also aids in regulating stress levels and promoting overall well-being.

Are there any common symptoms of DHEA imbalance linked to thyroid issues?

Symptoms can include fatigue, weight changes, mood swings, and hair loss. These imbalances may also contribute to fluctuations in energy levels and affect overall vitality.

Can DHEA benefit thyroid health?

Research suggests that DHEA supplementation may benefit individuals with thyroid conditions by potentially improving hormone balance and supporting bone density.

What are some side effects or considerations for using DHEA in thyroid conditions?

Possible side effects include acne, hair loss, and changes in blood sugar levels. It’s important to consult with a healthcare professional before starting any new supplement regimen.

How does 7-Keto DHEA impact thyroid disorders?

7-Keto DHEA has been studied for its potential to support healthy metabolism without affecting the body’s hormonal balance. Research indicates it may have positive effects on individuals with thyroid disorders.