Causes of High TSH Levels: What’s Really Going on and What You Can Do To Feel Like Yourself Again
After months of unexplained fatigue, weight gain, and brain fog, a visit to your doctor reveals you have elevated TSH levels.
High TSH is often a sign of a thyroid imbalance, but understanding the “why” behind the number can be confusing. Are you deficient in a key nutrient? Do you need to make better lifestyle choices? Are you doomed to feel this way forever?
Here, we address common causes of high TSH levels, answer your most common questions, and point you in the right direction for lasting thyroid balance.
Table of Contents
What Is TSH?
Your pituitary gland produces thyroid-stimulating hormone (TSH) that affects T3 (triiodothyronine) and T4 (thyroxine) and helps regulate thyroid hormone levels throughout your body.
The process begins in your hypothalamus, which produces thyrotropin-releasing hormone (TRH), and creates a chain of events that helps keep your body in working order.
TRH signals your pituitary gland to release TSH, which pushes the thyroid gland to release the thyroid hormones. These thyroid hormones are vital for regulating overall bodily functions, including your:
- Metabolism: Impact your weight and energy levels by regulating how quickly your body burns calories
- Heart function: Influence the rate and rhythm of your heart
- Body temperature: Affect heat production in your cells, which regulate your body temperature
- Brain development: T3 and T4 are essential for normal brain development, especially in infants and children
- Muscle functions: Affect the way your muscles relax and contract
- Skin and bones: T3 and T4 are partially responsible for maintaining your skin and bones by assisting with cell turnover
- Other body functions: Regulate digestion, menstruation, and cholesterol
You may be diagnosed with hyperthyroidism (low TSH levels) or hypothyroidism (high TSH levels) if your thyroid isn’t functioning properly.
Symptoms of High TSH
When TSH is high, the symptoms may not be noticeable because they can be attributed to other causes. The onset may also be gradual, making them harder to recognize.
Symptoms of high TSH include:
- Weight gain
- Constipation
- Slowed heart rate
- Dry skin
- Hair loss
- Cold intolerance
- Muscle aches
- Fatigue
- Menstrual irregularities
- Fatigue and low energy
- Cognitive issues
- Muscle and joint problems
If you’re struggling to determine the cause of high TSH levels, Dr. Sergi at HealthierU offers a holistic hypothyroidism treatment in Brooklyn. Her decades of experience and desire to help people solve their health problems in a natural, non-toxic way can put you on the path to resolving your thyroid issues.
What Can Cause High TSH Levels? 8 Common Factors
#1: Hashimoto’s Disease
The most common cause of hypothyroidism (underactive thyroid) in the United States is Hashimoto’s disease.
This autoimmune disorder produces antibodies that mistakenly attack the thyroid gland, causing the hormone-producing cells to become inflamed and damaged. As a result, the thyroid doesn’t produce the amount of T3 and T4 your body needs to function properly.
With fewer hormones in your bloodstream, your pituitary gland is signaled to release more TSH. Since the thyroid can’t handle the increased TSH efficiently, it builds up in your bloodstream and causes high TSH levels.
#2: Iodine Deficiency
When the body lacks iodine, it’s unable to produce the right amounts of T3 and T4. In turn, the pituitary gland releases more TSH to signal its need for more T3 and T4, causing the thyroid to develop a goiter.
With severe iodine deficiency, hypothyroidism may develop. Caused by iodine deficiency, this autoimmune disease negatively affects the body, especially brain development in infants and children. Pregnant women, breastfeeding mothers, and young babies are most
susceptible to iodine deficiency because more of this mineral is needed in these stages of life.
#3: Medications
Medications can indirectly affect TSH levels by interfering with thyroid hormone production, absorption, or metabolism. Some medications can cause an increase in TSH upon initial use that may level out after the medication has been taken over time, while others may continue to cause TSH disruptions.
Medications that may affect TSH levels include:
- Lithium: Used to treat bipolar disorder, it interferes with the synthesis and release of thyroid hormones, which can trigger the body to produce more TSH.
- Amiodarone: This heart medication contains high levels of iodine, which disrupt thyroid hormone production by causing high TSH levels.
- Calcium, antacids, and iron supplements: These supplements bind to thyroid hormones during digestion in the gut, preventing their absorption and, in turn, increasing TSH levels.
- Carbamazepine and phenytoin: These anti-seizure medications can cause thyroid hormones to be used by the body’s cells at a much faster metabolic rate, which may cause high TSH levels in your blood.
#4: Thyroidectomy
Thyroidectomy is the partial or full surgical removal of the thyroid gland due to:
- A cancer diagnosis
- Large nodules
- Cysts
- Biopsy to determine cancer
- Hyperthyroidism
Without a thyroid, the body is unable to produce the T3 and T4 needed to regulate many body functions, and to compensate for the lack of these hormones in the bloodstream, the pituitary gland signals an overproduction of TSH.
#5: Pregnancy
In early pregnancy, the production of HCG (human chorionic gonadotropin) can suppress TSH levels temporarily. As the pregnancy progresses, the demand for thyroid hormones increases because of the developing fetus.
Estrogen also boosts the production of a protein called thyroxine-binding globulin (TBG) that binds to thyroid hormones and increases the total levels of T3 and T4 in the blood. In turn, TSH may rise to meet demand.
#6: Pituitary Disorders
In
rare cases, a person may have a TSH-secreting pituitary adenoma (usually 1 or 2 cases per million), a typically benign tumor that produces excessive TSH. A TSH-secreting pituitary adenoma may be difficult to identify because its symptoms are similar to primary hyperthyroidism. Blood tests and an MRI or CT scan may help identify the adenoma, whose symptoms include:
- Difficulty sleeping
- Irritability
- Nervousness
- Increased perspiration
- Rapid heart rate
- Brittle hair
- Thinning skin
- Muscle weakness
In rare cases, someone may have a genetic condition called
familial isolated pituitary adenoma (FIPA). This hereditary condition makes a person more prone to developing pituitary tumors, some of which may secrete TSH.
#7: Excess Weight
Overeating can cause thyroid dysfunction over time because it leads to an increase in T3 and, in turn, TSH. This is the body’s response to metabolic changes as it tries to regulate energy balance and metabolism due to excess weight.
Being severely
overweight can also cause high TSH levels due to increased
leptin, a hormone that helps regulate body weight and tells your brain you’ve had enough to eat. Leptin may also stimulate the release of TRH, which signals the pituitary gland to release more TSH.
#8: Aging
TSH levels increase as we age. In some cases, your pituitary gland may become less sensitive to thyroid hormones, and even if your body is producing normal amounts of T3 and T4, it may take more TSH to stimulate the thyroid gland.
In other cases, your body may not produce enough T3 and T4, triggering it to produce more TSH to compensate.
Due to the natural increase in TSH levels, the older population has higher cases of misdiagnosed hypothyroidism.
Commonly Asked Questions About What Causes High TSH Levels
What Is Considered A Dangerously High TSH Level?
A "dangerously high" TSH is generally defined as anything above 10 mIU/L, with levels exceeding 20 mIU/L considered severe.
What Can Cause False High TSH Levels?
False causes of high TSH levels can most commonly be attributed to:
- Medications including biotin, lithium, amiodarone
- Lab assay interferences (like heterophile or macro-TSH antibodies)
- Recovering from acute illnesses
- Thyroid-specific variations such as subclinical hypothyroidism and iodine deficiency
What Should I Do if I’m Experiencing Symptoms of High TSH?
Since symptoms of high TSH can coincide with other common conditions, you should talk to your healthcare provider. They’ll consider your symptoms and complete blood work along with any other necessary tests to diagnose your condition.
At HealthierU, we specialize in women’s health, wellness, and nutrition, determining the
cause of thyroid imbalances and addressing them through holistic nutrition. Request a free consultation today.
Take Charge of Your Thyroid Health the Natural Way With HealthierU
At HealthierU, we’re committed to helping you get to the root of your symptoms through a holistic approach to healing that’s focused on your health concerns and goals.
As specialists in women’s health and wellness, we identify and alleviate your health-related symptoms using:
- Lifestyle adaptations
- Dietary changes
- Whole food concentrates
We’ll get you on the path to healing and work on eliminating the symptoms without fear of return.
Begin your journey to healing by scheduling a free consultation with HealthierU today.
