*Source: https://www.years.co/en/hashimoto* Hashimoto's thyroiditis # Detect Hashimoto's early, and monitor it wisely. Hashimoto's is the most common cause of an underactive thyroid and often develops over years before anything is noticed. In the YEARS check-up, TSH, the free thyroid hormones and a thyroid ultrasound run in every programme. If something stands out, we follow it up specifically and decide with you whether to treat or to monitor. Free intro call Book appointment 3 thyroid values in every programme: TSH, FT4, FT3 7–14 % of the population carry TPO antibodies 5–10× more common in women than in men The short answer ## What is Hashimoto's, and how does it show up? Hashimoto's thyroiditis is a chronic inflammation of the thyroid. The immune system produces antibodies against the body's own thyroid tissue, above all against thyroid peroxidase (TPO) and thyroglobulin (Tg), and over years the gland can lose function as a result. Women are affected five to ten times more often than men, usually starting between 30 and 50. Hashimoto's is detected in stages. TSH reacts first, the free hormones FT4 and FT3 show whether the thyroid still delivers enough, antibodies confirm the cause, and ultrasound shows the typical hypoechoic tissue. What each value means is explained in detail in our article on thyroid levels TSH, FT3 and FT4 . One thing matters most for interpretation: positive antibodies alone are not yet a disease, and a mildly raised TSH does not need immediate treatment. What decides is the course over several measurements, and that requires a baseline. From our team ## How our co-founder experienced his Hashimoto's diagnosis at YEARS Jürgen Mehrtens Co-Founder & CEO of YEARS In January Jürgen's TSH was 1.73. By the end of March it was 9.28, more than fivefold in just over ten weeks. His thyroid antibodies were clearly elevated, and the diagnosis was Hashimoto's. He had no symptoms, but a very stressful stretch of work. In between were six blood draws and many conversations at our clinic. - 1.73 January - 9.28 End of March - 8.30 Follow-up - 4.80 Follow-up - 5.39 Follow-up - 3.35 October TSH in mU/l, six measurements. Shaded: reference range of about 0.4–4.0 mU/l, depending on laboratory and age. Dashed: 10 mU/l, above which guidelines usually recommend treatment up to age 75. ### The first decision was a decision against Together with his physician Alexandru Ardelean, Jürgen decided not to take thyroid hormone for the time being. Large trials show no benefit in mild hypothyroidism without symptoms. Instead his values were measured every six to eight weeks, and the levels at which treatment would start after all were agreed in advance. That close measurement is what made waiting a responsible choice. ### The course TSH came down via 8.30, 4.80 and 5.39 to 3.35. FT4 is back in the middle of the reference range and the antibodies have more than halved. How much of that was down to the accompanying measures cannot be said. Courses like this can also normalise on their own. ### Reading the data backwards Jürgen's first assessment at YEARS was in November 2024, so the data could be read backwards. His monocytes, a group of white blood cells, were already elevated then, more than a year before his thyroid showed anything. Together with an elevated IgA, that pointed to longer-running immune activation, with the stress more likely the trigger than the cause. Because Hashimoto's occurs together with coeliac disease more often than chance, the next step was to rule it out. ### Context changes decisions LDL and ApoB had risen too. With low Lp(a), very low hsCRP and a good omega-3 index his overall risk was low, so the lipids are being monitored rather than discussed as a case for a statin. On top of that, an underactive thyroid slows the clearance of LDL by the liver. Whether the lipids come down as TSH settles is what the next measurement will show. “A single lab value tells you very little. Diagnostics becomes valuable when it runs over time, connects values to each other and ends up changing a concrete decision.” Jürgen Mehrtens The autoimmunity has not gone away, the antibodies are still positive. The thyroid is working normally for now, and Jürgen keeps measuring. His own course, not medical advice. Jürgen's post on LinkedIn In the YEARS check-up ## What we measure in you, and what we order specifically The thyroid is part of every programme, as laboratory values and as an image. Antibodies are ordered when they answer a question, and everything is assessed together with the values alongside. In every programme ### TSH The control hormone from the pituitary reacts first when the thyroid starts to lag. That makes it the most sensitive entry value. In every programme ### FT4 and FT3 The free thyroid hormones show whether the gland still delivers enough despite a raised TSH. They decide whether hypothyroidism is subclinical or overt. In every programme ### Thyroid ultrasound Size, structure, nodules and the lymph nodes of the neck. Hypoechoic, uneven tissue fits Hashimoto's, often before the values change. When TSH is raised ### TPO and Tg antibodies Antibodies against thyroid peroxidase and thyroglobulin confirm the autoimmune cause. We order them specifically when TSH is raised. As agreed ### Trajectory rather than snapshot An abnormal value is repeated before anything is decided. The levels at which treatment would start are agreed with you in advance. In context ### The values alongside LDL and ApoB, the blood count and, where indicated, coeliac antibodies. Only in context does it become clear what the thyroid finding means for you. What the trials say ## When to treat, and when monitoring is the better choice With overt hypothyroidism, a raised TSH and a low FT4, treatment with thyroid hormone is standard and works well. The more common case is a different one: TSH mildly raised, FT4 normal. That is called subclinical hypothyroidism. Here the guidelines are cautious. The German general practice guideline (DEGAM) advises against treatment with a TSH up to 10 mU/l without symptoms, regardless of age. A large randomised trial in older adults found no improvement in symptoms or tiredness from levothyroxine, and an international guideline in the BMJ recommends against hormone therapy for most adults with subclinical hypothyroidism. The situation is different when planning a pregnancy, during pregnancy, with marked symptoms or with values above 10. Monitoring means measuring, not forgetting. According to the DEGAM guideline, 2 to 5 percent of people with subclinical hypothyroidism develop overt hypothyroidism within a year, somewhat more often with antibodies. Conversely, a mildly raised TSH often normalises on its own: in a large analysis from Israel it was back in the reference range within five years in 62 percent. With positive antibodies that happens considerably less often. Both point to the same approach: measure repeatedly and agree in advance when treatment would start. ## When is a closer look at your thyroid worth it? Hashimoto's can affect anyone. In these situations it is more likely, though, and a baseline helps most. ### Women, especially around planning a pregnancy Women are affected considerably more often. Before and during pregnancy tighter TSH targets apply, and positive TPO antibodies change how care is planned. ### Thyroid disease in the family Autoimmune thyroid disease clusters in families. Anyone with a parent or sibling with Hashimoto’s is better off knowing their baseline early. ### Other autoimmune conditions Around one in seven people with Hashimoto's has a second autoimmune condition, such as coeliac disease, vitiligo or rheumatoid arthritis. Anyone with one of them should keep an eye on the thyroid. ### Fatigue, feeling cold, weight gain without explanation The typical signs of an underactive thyroid are non-specific and easily attributed to other causes. A TSH value settles the question quickly. ### Rising LDL without an obvious reason An underactive thyroid is one of the common treatable causes of raised blood lipids. The thyroid belongs on the list before cholesterol-lowering medication is discussed. Who interprets your thyroid values Doctor-medic Alexandru Ardelean Specialist in Internal Medicine „ True prevention begins when we stop waiting for symptoms. “ View profile → ## Frequently asked questions about Hashimoto's What is Hashimoto's thyroiditis? + Hashimoto's thyroiditis is a chronic inflammation of the thyroid in which the immune system produces antibodies against the body's own thyroid tissue, above all against thyroid peroxidase (TPO) and thyroglobulin (Tg). Over years the thyroid can lose function as a result. In countries with adequate iodine supply, Hashimoto's is the most common cause of an underactive thyroid, and women are affected considerably more often than men. Many people carry the antibodies without their thyroid ever declining. Hashimoto's is therefore less a single finding than a course worth knowing and monitoring. What gets treated is not the inflammation itself but, where needed, the underactive thyroid, with thyroid hormone. How is Hashimoto's diagnosed? + In stages. It starts with TSH, the control hormone from the pituitary, because it reacts first when the thyroid begins to lag. If it is raised, the free hormones FT4 and FT3 show whether the gland still delivers enough. Antibodies against TPO and Tg confirm the autoimmune cause; about 9 in 10 people with Hashimoto's have raised TPO antibodies, about 7 in 10 raised Tg antibodies. Ultrasound completes the picture: hypoechoic, uneven tissue is typical and often visible before the values change. Because a single raised TSH can also be temporary, a follow-up measurement after a few weeks belongs in the process before a diagnosis or treatment is settled. Does Hashimoto's always need treatment? + No. What gets treated is not the antibody finding but an underactive thyroid, and not in every case. If TSH is clearly raised and FT4 low, thyroid hormone is standard and works well. If TSH is only mildly raised and FT4 normal, the guidelines are cautious: the German general practice guideline (DEGAM) advises against treatment up to 10 mU/l without symptoms, and a large randomised trial found no benefit on symptoms or tiredness in older adults. The situation is different when planning a pregnancy, during pregnancy or with marked symptoms. Monitoring means measuring regularly, with levels agreed in advance at which treatment would start after all. Does the YEARS check-up detect Hashimoto's? + It detects the signs, and it follows them up. Every YEARS programme includes TSH, FT4 and FT3 as well as an ultrasound of the thyroid and neck lymph nodes. That picks up both declining function and the typical ultrasound pattern. The antibodies against TPO and Tg are not part of the fixed panel. We order them specifically when TSH is raised, as happened with Jürgen. That follows the German GP guideline, which does not recommend antibody testing when TSH is normal. The greater value lies in the trajectory: anyone measured with us once has a baseline against which later changes can be interpreted. A specialist physician discusses the findings with you, in the context of blood lipids, blood count and your history. Are Hashimoto's and cholesterol connected? + Yes, through thyroid function. Thyroid hormones control how many LDL receptors the liver produces. With an underactive thyroid there are fewer, LDL is cleared from the blood more slowly and rises. That is why the 2016 European dyslipidaemia guideline explicitly names hypothyroidism as a cause of raised cholesterol to be considered before treatment. In practice: if LDL or ApoB rise without an obvious reason, TSH belongs in the work-up. And the other way round: once an underactive thyroid is treated or normalises, the lipids are worth measuring again before further steps are decided. That was the case with Jürgen too. I have TPO antibodies but normal thyroid values. What does that mean? + First of all, that your thyroid is working normally right now. Positive antibodies with a normal TSH are common and, on their own, not a condition that needs treatment. They do indicate a tendency: the risk of developing an underactive thyroid later is higher than without antibodies, especially if TSH is already in the upper range. It therefore makes sense to check TSH at regular intervals, around once a year, and sooner if symptoms appear or a pregnancy is planned. Taking hormone preventively is not indicated. More important than the antibody level itself is whether, and how quickly, TSH changes over time. Sources - Raised TSH in general practice: antibody prevalence, work-up, treatment thresholds, course DEGAM S2k-Leitlinie, AWMF 053-046, Stand 2023 - Hashimoto's thyroiditis, age at onset IQWiG, gesundheitsinformation.de - Hypothyroidism, AACE/ATA clinical practice guideline (sex ratio) Garber et al., Endocr Pract 2012 - Levothyroxine in older adults with subclinical hypothyroidism, TRUST trial Stott et al., N Engl J Med 2017 - Thyroid hormones for subclinical hypothyroidism, clinical practice guideline Bekkering et al., BMJ 2019 - Normalisation of a mildly raised TSH over five years Meyerovitch et al., Arch Intern Med 2007 - Less frequent normalisation with positive TPO antibodies Somwaru et al., J Clin Endocrinol Metab 2012 - Other autoimmune conditions in Hashimoto's Boelaert et al., Am J Med 2010 - Coeliac disease in autoimmune thyroid disease, meta-analysis Roy et al., Thyroid 2016 - Hypothyroidism and LDL receptors Duntas & Brenta, Front Endocrinol 2018 - European guidelines on dyslipidaemias Catapano et al., Eur Heart J 2016 (ESC/EAS) ## Read on The values in detail and the pages that belong with the thyroid. Understanding thyroid levels TSH, FT3 and FT4 in detail, with reference ranges. Check-up for women Hormones, thyroid and heart, tailored to women. Always tired, everything normal The causes that slip through a standard panel. Blood values and biomarkers Which markers run in which programme. Family history Clarify inherited risks early, autoimmune conditions included. Health check Berlin The programme where these values come together on a single day. ## Your TSH is abnormal, or Hashimoto's runs in your family? A free 15-minute call. Bring your values along. We tell you what we would measure, and also when your GP is the right next step. Free intro call (15 min) Reserve appointment ★ 4,9 · 71+ Google- reviews · PKV, Beihilfe & bKV reimbursable Medical Disclaimer This information is provided for general education and is not a substitute for professional medical advice, diagnosis or treatment. Please discuss findings and individual medical decisions with a qualified physician. Content is reviewed periodically against the current state of scientific evidence.