Subclinical hypothyroidism is when the thyroid gland doesn’t produce enough thyroid hormone, causing problems with metabolism, heart rate, and growth.
Subclinical hypothyroidism is rising, affecting more people and a more comprehensive population range. Thyroid issues used to be linked to older women who had a family history of thyroid disease, but that isn’t the case anymore.
Instead, the increase in diagnosed and undiagnosed thyroid diseases in all age groups has multiplied over the last few years, with a lack of consistent diagnosis guidelines leaving many to suffer needlessly and hopelessly with the symptoms of subclinical hypothyroidism.

What Is Subclinical Hypothyroidism?
Subclinical hypothyroidism, also known as mild thyroid failure, is when the thyroid doesn’t produce enough thyroid hormone. The thyroid is the small gland at the front of the neck producing hormones that regulate metabolism and several other body functions. With subclinical hypothyroidism, the thyroid is slowed with minimal or few symptoms.
Healthcare providers estimate it affects up to 10% of the population with no known thyroid issues. This number is in addition to those diagnosed with thyroid disease, estimated as high as 20% of the population.
Doctors disagree with why people develop subclinical hypothyroidism. Some doctors believe subclinical hypothyroidism is temporary and will correct itself, while others believe it is the start of full-blown autoimmune thyroid disease.
Causes of Subclinical Hypothyroidism
There are many potential causes of subclinical hypothyroidism, and the exact cause is often unknown. However, here are a few of the known causes.
Hashimoto’s disease:
However, the most common cause of subclinical hypothyroidism is
an autoimmune disorder known as Hashimoto’s disease.
In this condition, the body’s immune system attacks the thyroid gland, causing inflammation and damage to the gland leading to a reduction in the production of thyroid hormones. Other causes of subclinical hypothyroidism include radiation therapy to the neck or chest area or certain medications, including:
- Amiodarone – a medicine used to treat an irregular heartbeat ( arrhythmia)
- Lithium- a drug used to treat certain mental health conditions, including bipolar disorders and depression
- Interferons – a class of medicine used in the treatment of hepatitis C and certain types of cancer
Pituitary gland problems: The pituitary gland is a small gland located in the brain that helps to control the thyroid gland. If the pituitary gland is not working correctly, it can lead to subclinical hypothyroidism.
Thyroiditis: This is a general term for thyroid gland inflammation. Thyroiditis can be caused by a virus or by the body’s own immune system.
Risk Factors of Subclinical Hypothyroidism
Several risk factors may increase your risk of developing subclinical hypothyroidism. These include:
The main risk factor for subclinical hypothyroidism is having an autoimmune disorder such as Hashimoto’s disease. Other risk factors include:
- Hashimoto’s disease: This is the number one cause of subclinical hypothyroidism. Many patients are diagnosed with subclinical hypothyroidism before being diagnosed with Hashimoto’s.
- Age: Being over 60, since hypothyroidism is more common in older adults, especially women.
- Family history: A family history of thyroid disorders makes you more likely to develop thyroid disease yourself.
- Autoimmune disorders: If you have one autoimmune disease, such as type 1 diabetes or rheumatoid arthritis, you may be more likely to develop autoimmune thyroiditis.
- Goiter: Swelling of the thyroid gland.
- Pregnancy: Subclinical hypothyroidism is more common in pregnant women, which can lead to the following problems:

Subclinical Hypothyroidism During Pregnancy
Pregnancy complications linked to Subclinical hypothyroidism
If an underactive thyroid is left untreated during pregnancy, there are risks of problems occurring in both mother and baby.
These include:
- Anemia in the mother
- Pre-eclampsia in the mother causes fluid retention, high blood pressure, and growth problems in the baby.
- Congenital disabilities
- Stillbirth or miscarriage
- Premature birth or low birth weight
- Slowed physical and mental development of the baby
- Hemorrhaging after birth
These issues are usually avoidable if you are under your doctor’s or an endocrinologist’s care. Be sure to let your doctor know you are not feeling yourself, especially if you are pregnant or trying to get pregnant.
Symptoms of Subclinical Hypothyroidism
What are the symptoms? The symptoms of subclinical hypothyroidism are often subtle and may not be noticed. However, many symptoms of subclinical hypothyroidism mimic other conditions, so it’s easy to be confused with other medical issues.
Symptoms usually slow to develop, and you may not realize your medical problem for several years.
Common symptoms include:
- weight gain
- constipation
- depression
- tiredness
- being sensitive to cold
- muscle aches and weakness
- muscle cramps
- brittle hair and nails
- slow movements and thoughts
- pain, numbness, or a tingling sensation in the hand and fingers
- irregular or heavy periods
- loss of sex drive
- dry and scaly skin
Also, the elderly with underactive thyroids may develop depression and memory problems. In addition, children may experience slowed growth and development, while teenagers may start puberty earlier than expected.
Diagnosing a Thyroid Disorder
Subclinical hypothyroidism diagnosis starts with a blood test that measures thyroid stimulating hormone (TSH) levels in the blood. TSH is a hormone that helps to control the thyroid gland. A higher TSH level indicates poor thyroid gland function, slowing thyroid hormone production.
Other blood tests that may diagnose subclinical hypothyroidism include the T4 and thyroid auto-antibody tests.

Testing Thyroid function
A blood test checking your hormone levels reveals whether there’s a problem.
The thyroid function test checks the TSH and T4 in the blood.
Many healthcare providers refer to this as “free” T4 (FT4).
High levels of TSH and low levels of T4 could mean you have an underactive thyroid.
If your test results reveal raised TSH levels but normal T4, you may develop hypothyroidism. Therefore, your healthcare provider may request a blood test periodically to see whether you eventually develop full-blown thyroid disease.
Blood tests are also used for other measurements, such as checking the triiodothyronine (T3) hormone level. T3 is the active, usable thyroid hormone. However, this test is not offered unless your provider feels there is an issue or needs more information for a diagnosis.
Also, you may need a thyroid antibody test after a thyroid function test. These tests help diagnose or rule out autoimmune thyroid conditions like Hashimoto’s thyroiditis. A thyroid antibody test will only be recommended if it’s suspected you have an autoimmune thyroid condition.
FYI: Conventional doctors will only run a TSH blood test if you bring up symptoms. The reason is that most insurance companies will only pay for the TSH test, based on the CDC and FDA. So it will have to be approved beforehand if you need additional testing, like a free T3 or antibody test; this is also true if you need a scan or biopsy.

Subclinical Hypothyroidism Testing
Can and Do They Treat Subclinical Hypothyroidism?
Subclinical hypothyroidism is usually treated with thyroid hormone replacement therapy. This treatment involves taking a daily pill that contains the hormone thyroxine.
The treatment of subclinical hypothyroidism depends on the underlying cause. If the cause is unknown or the condition is not causing any symptoms, treatment may not be necessary.
However, treatment may be necessary if the condition is caused by an autoimmune disorder, such as Hashimoto’s disease.
If left untreated, subclinical hypothyroidism can lead to more severe problems such as heart disease, infertility, and goiters.
Conventional treatments for subclinical hypothyroidism:
The modern conventional treatment options for subclinical hypothyroidism include:
Levothyroxine: Which is the most common form of treatment for subclinical hypothyroidism. Levothyroxine is a synthetic for the thyroid hormone thyroxine. It is taken as a pill, replacing the missing thyroid hormone in your body.
Surgery: Surgery is sometimes needed to remove the thyroid gland. However, this is typically only recommended if you have a goiter (enlarged thyroid gland) or cannot take thyroid hormone replacement therapy.
Holistic treatments for subclinical hypothyroidism:
There are also options for holistic treatments for subclinical hypothyroidism.
Herbal supplements can help treat subclinical hypothyroidism, including:
Ashwagandha: This herb has been used for centuries in Ayurvedic medicine. It is known to help the body adapt to stress, and it is effective in treating subclinical hypothyroidism.
Guggul: Guggul is another herb used in Ayurvedic medicine for centuries. It is known for its ability to help regulate the thyroid gland and is effective in treating subclinical hypothyroidism.
Thyroid support supplements: Many supplements vital to thyroid function are deficient in those with subclinical hypothyroidism, so supplementing helps ease symptoms.
These include:
Iodine: Increase your intake of iodine-rich foods. Iodine is an essential mineral for the proper function of the thyroid gland.
Selenium: This trace mineral is essential for the thyroid gland’s proper function.
Vitamin B: B vitamins are vital to thyroid function and hormone regulation.
Functional medicine doctors recommend a complete vitamin B complex.
My doctor recommended a two-per-day multivitamin. He believes his patients get better absorption with the two-per-day formula; he also told me he takes the same multi, as does his wife, who has Graves’ disease.
Magnesium: Magnesium can potentially have interactions with thyroid medications. Many with poorly functioning thyroids are also magnesium deficient.
Tyrosine: This amino acid helps with the thyroid gland’s proper function, and many find supplementing with tyrosine helpful.
How to Ease The Symptoms of Subclinical Hypothyroidism?
If you talk to a conventional doctor, most likely, they will tell you that poor diet, stress, and environmental toxins have nothing to do with the sharp increase in autoimmune diseases.
However, if you talk to a holistic doctor, that will be the first thing they will tell you.
Holistic and functional doctors focus on improving your diet, reducing toxic exposures, and lowering stress to ease symptoms and heal the body rather than giving you a prescription.

Here are six toxins that are known to harm your thyroid!
These toxins disrupt thyroid function and lead to serious health issues.
Heavy Metals – The top four are aluminum, cadmium, lead, and mercury.
Children’s toys and cheap jewelry can contain lead; cadmium is in plastics, fertilizers, pigments, and batteries. Mercury and aluminum disrupt iodine uptake, plus mercury is in seafood and dental fillings.
Aluminum is also in cookware, vaccines, antacids, and deodorant.
Herbicides and Pesticides – Herbicides and pesticides interrupt the thyroid’s ability to use iodine. These chemicals have been linked to a higher risk of developing thyroid disease and cause thyroid hormone to leach from the body—the more your exposure to herbicides and pesticides, the higher your risk of developing thyroid problems.
Flame Retardants – The chemical that reduces the flammability of fabrics, clothing, furniture, and carpeting causes thyroid dysfunction. These chemicals contain bromine, a halogen that mimics thyroid hormone and attaches to thyroid hormone receptors lowering thyroid function. Bromine can be found in pool cleaners, pasta, drinks, and just about everything else.
BPA – This industrial chemical is used to manufacture plastics and epoxy resins. BPA is used in food storage containers and water bottles. BPA lines metal food cans, water supply lines, and bottle caps. In addition, BPA can be found in dental composites and sealants.
BPA exposure causes a wide range of health problems. For example, after damaging the thyroid gland, BPA can cause cardiovascular issues, reproductive problems, and an increase in breast and prostate cancer. Plus, it increases the risk of type 2 diabetes, weight gain, and asthma.
Fluoride – Many people are surprised to learn that fluoride disrupts the thyroid gland. Even though fluoride is used to prevent cavities, it also can damage your thyroid health. Research has shown that as little as two to five milligrams of fluoride over a few months can lower thyroid function. Unfortunately, that is about the amount of fluoride that you consume in fluoridated water each day. Therefore, filtering your drinking water could help increase your thyroid function and ease symptoms.
PFCs – PFCs (perfluorinated chemicals) disrupt thyroid function, especially in women. PFCs are used for several items, including takeout containers, pizza boxes, and even particular mattresses. PFC is a known endocrine disruptor that takes the body a long time to break down. PFCs are being phased out in the United States, but imported products could still contain PFCs.
Cleaning Up Your Diet

When we met to review my treatment plan with my functional medicine doctor, he handed me a three-inch thick binder full of information. He had included information on my disease (Graves’ disease), a recap of the medication adjustment he did, and dietary recommendations and guidelines that would help nourish and heal my body from the autoimmune disease.
I laughed and told him that he hadn’t included any recipes; that’s when he told me his wife had a thyroid health cookbook she purchased on the internet(to help ease her Graves’ disease symptoms.) He shared how this program helped him improve his health and his wife’s. I shared the link here: Hypothyroid Solution. I have had several readers share how helpful and informative the program is. (We may receive a commission when you purchase through the links in this post.)
I will also share that you have a new set of hormones raging if you are older and going through menopause. If this describes you, check out the Thyroid Factor. Readers have shared stories about how their health improved after following their recommendations.
When trying to remove toxins, reduce stress, and improve your diet, remember to look at all areas of your life and try to improve a few things each week. For example, I try new recipes weekly, use non-toxic laundry detergent (I use this now), and filter my water.
A little effort can make a huge difference in your health, especially when your thyroid needs your help!
Take care,
Corri
Resources
https://www.nhs.uk/conditions/underactive-thyroid-hypothyroidism/symptoms/
https://www.everydayhealth.com/hs/healthy-living-with-hypothyroidism/vitamins/