Thyroid Disorders Guide: Symptoms, Causes, and Management

Overview

Your thyroid is a small, butterfly-shaped gland at the base of your neck. It produces hormones that regulate your metabolism, energy levels, body temperature, heart function, and brain development. Thyroid disorders occur when the gland makes too much (hyperthyroidism) or too little (hypothyroidism) thyroid hormone, or develops abnormal growths (nodules) or enlargement (goiter). These conditions affect an estimated 20 million people in the U.S., are 5 to 8 times more common in women, and are mostly treatable with proper care.

Signs & Symptoms

Causes & Risk Factors

Hypothyroidism is most often caused by Hashimoto’s disease, an autoimmune condition where the immune system attacks the thyroid gland, reducing its ability to produce hormones. It can also result from thyroid surgery, radiation treatment to the neck, certain medications (like lithium), or iodine deficiency. Hyperthyroidism is most commonly caused by Graves’ disease, another autoimmune disorder that triggers excess hormone production, or by thyroid nodules that secrete too much hormone on their own.

• Being assigned female at birth
• Family history of thyroid disease
• Having another autoimmune condition (such as type 1 diabetes, rheumatoid arthritis, or lupus)
• Age over 60
• Previous thyroid surgery or radiation treatment to the neck
• Pregnancy or recent childbirth
• Taking certain medications, including amiodarone and lithium

Diagnosis

Diagnosing a thyroid disorder starts with a physical exam, during which your provider will feel your neck for swelling, lumps, or tenderness, and review your symptoms and medical history. They may order one or more of the following tests:

• Blood tests to measure thyroid-stimulating hormone (TSH) and free T4/T3 hormone levels (the most common initial test)
• Thyroid ultrasound to check for nodules, cysts, or enlargement of the gland
• Radioactive iodine uptake test to evaluate how well your thyroid is functioning and identify the cause of hormone overproduction
• Fine-needle aspiration biopsy if a nodule is found, to check for cancerous cells

Treatment & Management

Treatment is tailored to the type and severity of your disorder, as well as your overall health and personal preferences. For hypothyroidism, the standard treatment is a daily dose of levothyroxine, a synthetic version of the thyroid hormone your body is missing. For hyperthyroidism, options include anti-thyroid medications to reduce hormone production, radioactive iodine therapy to shrink the thyroid gland, or surgery to remove part or all of the thyroid. If you have non-cancerous nodules that are not causing symptoms, your provider may recommend regular monitoring instead of immediate treatment. Most people with thyroid disorders need lifelong treatment and regular follow-up appointments to check their hormone levels and adjust medication doses as needed. With consistent care, almost all people with thyroid disorders can manage their symptoms and live full, active lives.

Living With It

Small, consistent lifestyle adjustments can help reduce symptoms and support your overall health alongside medical treatment:

• Take your prescribed thyroid medication exactly as directed, at the same time each day (usually first thing in the morning, on an empty stomach, and 30-60 minutes before eating or taking other medications). Never skip doses or stop taking your medication without consulting your provider, even if you feel better.
• Keep a simple log of any symptoms you experience, including changes in energy, weight, mood, sleep, or temperature tolerance, to share with your provider at appointments. This helps your team adjust your treatment plan as needed.
• Eat a balanced diet that includes adequate iodine (found in seafood, dairy, and iodized salt), but avoid high-dose iodine supplements unless your provider recommends them. If you have hypothyroidism, talk to your provider about limiting very high intake of raw cruciferous vegetables (like kale, broccoli, and cauliflower) if they worsen your symptoms, though cooking these vegetables reduces any potential interference with thyroid function.
• Practice regular moderate exercise (like walking, yoga, or swimming) and stress-reduction techniques (like deep breathing or meditation) to boost energy, reduce stress, and support overall hormone balance.
• Aim for 7-9 hours of quality sleep each night to support hormone regulation, and avoid smoking and excessive caffeine, as both can worsen thyroid symptoms and interfere with medication effectiveness.