What is Hashimoto's Disease? Symptoms and Nutrition Tips

Hashimoto's disease is an autoimmune condition that occurs when your immune system mistakenly attacks your thyroid gland, located in the neck. Over time, this chronic attack damages the thyroid, preventing it from producing enough hormones—a condition known as an underactive thyroid. Quite common in the general population, this condition can be the root cause of many complaints, ranging from chronic fatigue to unexplained weight gain.

In Brief:

• Caused by the immune system attacking the thyroid gland.
• Seen seven to ten times more frequently in women than in men.
• The most common cause of reduced thyroid hormones (hypothyroidism).
• Treatment usually involves lifelong thyroid hormone supplementation.
• A healthy diet and lifestyle changes significantly relieve symptoms.

What is Hashimoto's Disease?

The thyroid gland is a small, butterfly-shaped organ located at the front of your neck that produces hormones (T3 and T4) to regulate your body's metabolic rate. In Hashimoto's disease (chronic lymphocytic thyroiditis), the body's defence mechanism—the immune system—perceives the thyroid gland as a foreign threat. Immune cells send antibodies to the thyroid tissue, triggering chronic inflammation.

This silent inflammatory process, which can last for years, gradually destroys the thyroid gland. When the gland can no longer produce enough hormones, your body's energy production and metabolic processes slow down. In regions like Türkiye, where iodine deficiency has largely been eliminated, this autoimmune disease is the most common cause of hypothyroidism (underactive thyroid). Although it is usually diagnosed in individuals between the ages of 30 and 50, it can appear in any age group, even in children.

Causes and Risk Factors

While it is not entirely clear why the immune system attacks its own tissues, a combination of genetic predisposition and environmental triggers is the most likely culprit. If you have a family history of thyroid disorders or other autoimmune diseases, your risk increases. However, a genetic legacy alone is not enough to cause the disease; a trigger is usually required.

Gender is the leading risk factor; women are far more susceptible to this disease than men. Having other autoimmune conditions like Type 1 diabetes, coeliac disease, rheumatoid arthritis, or lupus increases the likelihood of developing Hashimoto's. Environmental factors include excessive iodine consumption, radiation exposure to the neck area, certain viral infections, and intense chronic stress. Stress is a major factor that can disrupt the balance of the immune system and flare up autoimmune reactions.

What Are the Symptoms of Hashimoto's Thyroiditis?

In the early stages of the disease, there are usually no complaints. Over the years, as the thyroid gland is damaged and hormone levels drop, symptoms of Hashimoto's thyroiditis gradually emerge due to a slowing metabolism. Occasionally, in the early stages, hormones from damaged cells may suddenly leak into the bloodstream, causing a temporary period of palpitations and sweating (hashitoxicosis), but the condition ultimately shifts toward a slowdown.

The most common symptoms include:

• Extreme fatigue and sluggishness that persist even after eight hours of sleep.
• Feeling cold even in the summer, and an increased sensitivity to the cold.
• Unexplained weight gain or difficulty losing weight despite dieting.
• Excessively dry, pale, and flaky skin.
• Hair loss, thinning hair, and easily breakable nails.
• Chronic constipation and a sluggish digestive system.
• Muscle weakness, joint pain, and cramps.
• Forgetfulness, difficulty focusing (brain fog), and a depressed mood.
• A deepened or hoarse voice.
• A feeling of fullness in the neck or a visible swelling (goitre).

How Is It Diagnosed at the Hospital?

When you consult a physician with the above complaints, a detailed physical examination is performed first. Your doctor will manually examine your neck to check for any enlargement (goitre) or nodules in the thyroid gland. Detailed investigations may be required to determine whether any detected masses are benign. For more information on this topic, you can review our article titled What is a Thyroid Nodule? Symptoms and Treatment Methods.

A definitive diagnosis is made through blood tests. When the pituitary gland in the brain notices that the thyroid is underperforming, it increases the secretion of TSH (Thyroid Stimulating Hormone) to stimulate it. Therefore, high TSH and low Free T4 levels in the blood indicate an underactive thyroid. To prove the autoimmune nature of the disease, Anti-TPO and Anti-Tg antibodies are checked; elevated levels of these antibodies confirm the diagnosis of Hashimoto's. Additionally, a thyroid ultrasound is performed to evaluate the structure of the thyroid gland, the extent of the damage, and the presence of any nodules.

The Treatment Process and the Hashimoto's Diet

There is no cure that completely eradicates the disease; treatment is based on replacing the missing thyroid hormone synthetically (levothyroxine) from the outside. The medication is usually taken in the morning on an empty stomach, at least half an hour before breakfast. To find the correct dose, a blood test is initially done every 6-8 weeks; once hormone levels are balanced, an annual check-up is sufficient.

Alongside medical treatment, a nutritional plan known as the Hashimoto's diet plays a critical role in lowering antibody levels and reducing symptoms. An anti-inflammatory diet that supports gut health should be adopted. Many patients develop sensitivities to gluten and dairy products; removing these foods from your diet can alleviate complaints like fatigue and bloating.

Foods rich in selenium, such as Brazil nuts, eggs, and seafood, support thyroid function. Zinc and Vitamin D supplements can also be used under a doctor's supervision. Staying away from processed foods, refined sugar, and soy products are the best steps to protect your metabolism. To learn about the dangers of incorrect diets during the weight loss process, you can check out our article titled What Are the Harms of Rapid Weight Fluctuation on the Metabolism?.

Complications and Risk Groups

When left untreated, the disease paves the way for serious complications in the body. A slowing metabolism reduces the liver's ability to process cholesterol; this leads to elevated levels of bad cholesterol (LDL) and an increased risk of heart disease. An enlarged thyroid gland (goitre) can eventually press against the windpipe or oesophagus, creating difficulties in swallowing and breathing.

In untreated cases, psychological issues such as depression, anxiety, and a loss of sexual desire can deepen. Women who are pregnant or planning a pregnancy are the most crucial risk group. Uncontrolled low thyroid hormone levels during pregnancy can lead to delayed brain development in the baby, a risk of miscarriage, and premature birth. Although very rare, a life-threatening condition called "myxoedema coma" can develop in severely ill patients who have been untreated for many years, often triggered by infection or exposure to the cold.

When to See a Doctor

If you notice persistent fatigue that affects your daily life, weight gain despite dieting, significantly dry skin, ongoing constipation, or a permanent hoarseness in your voice, you should consult an endocrinologist without delay. Especially if you have a family history of thyroid disease, it is beneficial to have your thyroid functions checked during routine blood tests, even if you have no complaints.

The following symptoms may be signs of myxoedema coma, a rare but medical emergency requiring immediate intervention. If you notice this condition, you should immediately call 112 or go to the nearest emergency room:

• Extreme sleepiness, inability to wake up, or confusion.
• A sudden and dangerously low drop in body temperature (hypothermia).
• Severe slowing or difficulty in breathing.
• A very slow heart rate and low blood pressure.
• Excessive swelling (oedema) in the face, tongue, and legs.

The Process at BHT CLINIC

The diagnosis and treatment of thyroid diseases are meticulously carried out by specialist physicians in the Endocrinology and Metabolism department at our hospital. At BHT CLINIC İstanbul Tema Hastanesi, a definitive diagnosis is quickly established using up-to-date laboratory tests and high-resolution ultrasound equipment. Disease management is not limited to medication; a holistic approach is provided by creating personalised nutrition plans accompanied by our expert dietitians.

Bringing any previous blood test results and thyroid ultrasound reports with you when you come to our hospital will speed up the process. In unexpected situations or for sudden complaints, we are always by your side with our 24/7 emergency department and uninterrupted laboratory infrastructure.

Frequently Asked Questions

Can Hashimoto's disease be completely cured?

There is no definitive cure that completely eliminates the autoimmune nature of the disease. However, by replacing the missing thyroid hormone with medication and adopting proper nutritional habits, the disease can be fully controlled, allowing patients to lead a normal, healthy life.

Can Hashimoto's patients lose weight?

Yes, you can lose weight. When your blood hormone levels return to normal with medication, your metabolism also regains its normal speed. It is possible to reach your ideal weight with a healthy nutrition plan and regular exercise.

Does Hashimoto's cause hair loss?

Because a deficiency in thyroid hormones slows down the renewal cycle of hair follicles, thinning and hair loss are common complaints. A few months after starting medication and balancing hormone levels, hair loss usually stops, and the hair regains its former health.

Is Hashimoto's genetic?

There is a strong genetic predisposition in the development of the disease. Individuals who have first-degree relatives, such as a mother, sister, or aunt, with a thyroid condition have a much higher risk of developing this disease compared to those with no family history.

Should I use iodised salt?

In Hashimoto's patients, excessive iodine consumption can increase the immune system's attack on the thyroid gland. Therefore, unless your doctor advises otherwise, you should avoid iodine supplements and definitely consult your doctor regarding the use of iodised salt.

To book an appointment and have your detailed tests done, you can visit our BHT CLINIC Appointment page or reach us 24/7 via our call centre at 0850 811 34 00.

This article is for informational purposes only; please consult your physician for diagnosis and treatment.