Hashimoto's Disease
An autoimmune condition and the most common cause of hypothyroidism.
Definition
Hashimoto's disease is an autoimmune disorder in which the immune system gradually attacks and damages the thyroid gland, reducing its ability to produce hormones. It is the most common cause of hypothyroidism, producing fatigue, weight gain, and cold intolerance. Treatment usually involves lifelong thyroid hormone replacement.
The Diagnostic Journey
A typical path patients take with Hashimoto's Disease — from first symptoms to living with the condition. Click each stage to expand.
Many invisible illnesses begin with vague, intermittent symptoms such as fatigue, pain, or changes in weight or mood. Because these signs are non-specific and can come and go, they are frequently attributed to stress or overwork, which is one reason diagnosis is so often delayed.
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Related Glossary Terms
Sources & References
This page draws on trusted, authoritative health resources. For medical decisions, always consult a qualified healthcare professional.
- Hashimoto's DiseaseNational Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIHGovernment Health Agency
- Thyroid Information for PatientsAmerican Thyroid AssociationProfessional Medical Society
- Endocrine Diseases: ThyroidNational Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIHGovernment Health Agency
- Health Topics: Trusted Consumer Health InformationMedlinePlus, U.S. National Library of MedicineGovernment Health Agency
- Health Topics A-ZMedlinePlus, U.S. National Library of MedicineGovernment Health Agency
- Health Library: Diseases & ConditionsCleveland ClinicAcademic Medical Center
Content Review
- Last Reviewed
- July 2026
- Last Updated
- July 2026
- Content Type
- Educational Documentary Companion
- Evidence Standard
- Evidence-Informed
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