What is hypothyroidism? What are the signs, symptoms, and causes of hypothyroidism? Learn more about the symptoms, causes, and concerns that come with a diagnosis of hypothyroidism.

Hypothyroidism 101

Hypothyroidism (a low functioning thyroid) is the most common cause of thyroid dysfunction, characterized as an underactive thyroid, where the thyroid gland doesn’t make enough thyroid hormones.

Lack of thyroid hormones leads to universal decline in the cellular function of all body systems and processes. 

What is the Thyroid? 

The thyroid is a vital, butterfly-shaped hormone gland, located in your throat, that acts as your metabolic mothership.

The thyroid plays a major role in the metabolism, growth and development of the human body and it helps to regulate many body functions by constantly releasing a steady amount of thyroid hormones into the bloodstream (also known as T3 and T4 thyroid hormones).  In fact, every cell in your body has receptors for thyroid hormones.

Your thyroid hormones are responsible for regulating processes like: 

  • Temperature regulation
  • Heart rate and blood pressure
  • Activation of the nervous system
  • Detoxification
  • Steroid (sex) hormone production and function
  • Fat, carbohydrate, protein and cholesterol utilization and metabolism

  • Bone me
  • Brain growth and development (helping you get smarter and think more clearly)
  • Caloric energy and nutrient use
  • Digestive function
  • Immune system regulation
  • Growth (in children, as well as skin, nails, hair, wound healing)


For instance, if the body needs more energy in certain situations – such as more heat when it’s cold outside, more immune boosting cell action in the face of allergy season, or more support during pregnancy to grow a baby – the thyroid gland produces more hormones to give your body more “umph” to make it happen.

However, in the case of hypothyroidism, your thyroid gland does not produce enough thyroid hormones, resulting in slowed thyroid function and imbalances in your overall health as a whole.     

Who Gets Hypothyroidism? 

More than 20 million Americans have some form of thyroid disease or disorder, including hypothyroidism, hyperthyroidism, thyroid cancer and/or Hashimoto’s Thyroiditis, an autoimmune condition responsible for up to 90% of cases of hypothyroidism and the most prevalent autoimmune disorder in the United States. 

women talking about hypothyroidism

Of these cases, nearly half of them are hypothyroidism (a low functioning thyroid), and sometimes they are both hypothyroidism and Hashimoto’s Thyroiditis, since Hashimoto’s usually comes before full blown hypothyroidism. 

Hypothyroidism can go undiagnosed for years, with up to 60 percent of people who are currently unaware of their condition. Women are more at risk than men of developing the dysfunction, with 1 in 8 women developing a thyroid disorder during her lifetime. In addition, countless more people have what is known as “subclinical hypothyroidism,” a dysfunctional thyroid and lab markers that are progressive (on the way to disease) without any diagnosis from a physician or healthcare professional, despite experiencing common thyroid symptoms. 

Unfortunately, conventional medicine typically only recognizes thyroid disorders when they are in their most progressed or advanced stages, and typically only uses 2 or 3 blood markers (of many blood markers and signs and symptoms) to determine whether a person has the disease. 

Consequently, many people go “under the radar,” living with symptoms of hypothyroidism for years before it is actually caught and it has fully progressed. 

Hypothyroidism Symptoms

The symptoms of hypothyroidism are diverse since the thyroid affects practically every process in the body. Common symptoms of hypothyroidism, or an under functioning thyroid, include:

  • Difficulty losing weight or gaining weight
  • A slow or dysfunctional metabolism
  • Unexplained weight loss or weight gain
  • Cold often
  • Easily tired or fatigued, despite sleep or coffee
  • Needing coffee to “function”
  • Low Vitamin D levels
  • Tend towards constipation or bloating
  • Low neurotransmitters (dopamine/serotonin) often resulting in poor concentration and /or low mood

  • Dry skin
  • Low immune function
  • Brittle nails
  • Insomnia or poor sleep
  • Low blood pressure and/or heart rate
  • Hair loss
  • Enlarged thyroid
  • High cholesterol
  • Irritability, depression and/or anxiety
  • Low libido
  • Fatigue/low energy
  • Poor recovery from workouts/injuries
  • Slow reflexes
  • Irregular uterine bleeding


Hypothyroidism Causes

While genetics play a great role in hypothyroidism, hypothyroidism itself typically does not manifest unless the “perfect storm” of environmental, lifestyle and nutritional triggers set it off. 

Common triggers to hypothyroidism include:

  • Underlying gut pathologies (bacterial overgrowth, low stomach acid, parasitic infection, bacterial infection, H. pylori)
  • Chronic stress & HPA Axis Dysfunction (adrenal, cortisol and hormone imbalances)
  • Underfunctioning pituitary (controls the growth, development and function of other endocrine glands)
  • Environmental toxic burden
  • Low immune function 
  • Reduced oxygen to cells (iron deficiency or in some cases, iron overload)
  • Blood sugar imbalances
  • Other chronic diseases, inflammation or underlying infections (Lyme disease, hepatitis C, IBD, etc.)
  • Long-term medication use or drug-induced hypothyroidism (overdose of thyroid hormones or other hormones)
  • Nutrient deficiencies (selenium, copper, iodine, zinc, pyridoxal 5 phosphate, zinc, magnesium)

Thyroid Nutrients 101

Of this list, one of the most modifiable risk factors for hypothyroidism comes down to your dietary intake of essential nutrients, along with a healthy gut microbiome (to be able to digest those nutrients in the first place). 

food good for hypothyroidism

Unfortunately, our modern-day, industrialized diets of the 21st century strip our body void of essentials necessary to make the thyroid properly. Even more, if you aren’t digesting your nutrients in the first place, your body (and thyroid) run into more problems with underlying pathologies, such as bacterial overgrowth, yeast infections, and dysbiosis (imbalances in “good” and “bad” bacteria) impairing nutrient absorption and thyroid function as well.

The following is a list of necessary nutrients required for healthy thyroid function–as well as caution to not go overboard on them either (since toxicity of these nutrients can also inhibit thyroid function). 







Fermented foods (sauerkraut, kimchi, kefir, yogurt, pickled veggies), prebiotic foods (cooked & cooled potatoes/sweet potatoes, cooked & cooled white rice, green plantains), Supplements: soil-based probiotics, partially hydrolyzed guar gum (prebiotic), short-chain fatty acids (butyrate) 1-2 fermented foods (condiment sized serving)/daily, 1-2 starchy tubers/prebiotic foods; Supplements: 1 probiotic in the morning & evening, ½-1 tsp. Prebiotic fiber, 1 short-chain fatty acid capsule with meals
Iodine Sea vegetables (kelp flakes, kelp, wakame, hijike, arame, nori, etc.), dairy products, cod, iodized salt Required for reproduction and growth, and it’s only known function is the synthesis of thyroid hormone; Can be helpful if TSH markers are “off”; Consume food sources in small-moderate doses (kelp flakes 3-4 times per week, cod 1-2 times per week, iodized salt occasionally, etc.); If deficient (according to a hair or urine test), consider supplementing with 100 mcg/day and increase up to 1000 mcg if deficiency is severe for 30-90 days, then re-test; Note: If you have Hashimoto’s, iodine typically will often cause “flares” if you are deficient in selenium too (consider taking with selenium)
Selenium Ocean fish, Brazil nuts, ham Selenium is essential for the conversion of T4 to T3; Studies also show benefits of selenium supplementation in treating autoimmune thyroid conditions to reduce inflammation (reducing inflammation may limit damage to thyroid tissue); About supplements: the best strategy is to first ensure adequate selenium intake through the diet and possibly to use testing for selenium levels at baseline to determine whether selenium supplementation is needed (The normal concentration in adult human blood serum is 70 to 150 ng/mL)
Iron Oysters, clams, liver, venison, beef Iron deficiency reduces production of thyroid hormone; However, excess iron damages the hypothalamus, pituitary, and thyroid (Fact: people with hemochromatosis or iron overload are 80 times more likely to have hypothyroidism); Eat foods with iron in them or use a liver capsule supplement (if organ meats are not preferred); Only supplement with iron if lab test levels indicate deficiency outside of these markers:

 Serum Iron: 40-155 ug/dL


Men: 30-400 ng/mL

Pre-Menopausal Women: 15-150 ng/mL

Post Menopausal Women: 15-150 ng/mL

Transferrin Saturation: 15-55%


Men: 250-450 ug/dL

Pre-Menopausal Women: 250-450 ug/dL

Post Menopausal Women: 250-450 ug/dL

UIBC: 150-375 ug/dL

sTfR (soluble transferrin receptor): 12.3-27.3 nmol/L

Zinc Oysters, liver, crab, lobster, beef, pastured eggs (Note: spinach, beans and nuts also have zinc, but are not bio-available due to difficult-to-digest components) Required for synthesis of TSH; If deficient (outside of: 81–157 µg/dL), supplement with 30 mg for 8 weeks, then recheck levels
B12 & B2 B12: Clam, liver, oyster, mackerel, sardine; B2: Liver, mushrooms, seaweed, spinach Required for synthesis of TSH
Magnesium Dark leafy greens, Dark chocolate, Almonds, Banana, Pumpkin seeds, Avocado, Halibut Required for synthesis of TSH; Consume 600-800 mg/day between foods and supplements; Supplementing with 300-400 mg/day of chelated magnesium such as Magnesium Glycinate can be helpful
Vitamin C Red pepper, kiwi, broccoli, citrus, brussels sprouts, kale Boosts adrenal function to support hormone health; also leads to less suppressed T4 and T3 levels; Supplement: 500-1000 mg/day if you have low T4 & T3 and high stress
Vitamin A Organ meats, cod liver oil, seafood, grass-fed dairy Regulates thyroid hormone metabolism and inhibits elevated TSH; Supplement: Extra Virgin Cod Liver Oil, ½ tsp-1 tsp/day 
Vitamin D Cod liver oil, cold-water fatty fish, pastured egg yolks, sun exposure, supplementation if necessary Boosts immune function and suppresses autoimmune attack on the thyroid; Deficiency is highly connected to Hashimoto’s and hypothyroidism; Check levels aiming for this reference range: 35–60 ng/mL; If deficient,supplementation may be warranted for 4 weeks with upwards of 5,000-10,000 IU (depending on severity), then recheck levels

Diagnosis: How Do I Know if I Have Hypothyroidism? 

Good question. Unfortunately, conventional medicine does not always recognize signs and markers of thyroid dysfunction, despite metabolic breakdown and symptoms in line with hypothyroidism. 

Traditional blood work testing does NOT do a thorough evaluation for hypothyroid markers.  

Conventional medicine states that you are only hypothyroid if you have:

  • A TSH level above 4.5 
  • T4 level between below 4.87 

If not, then you are “healthy” and “in the clear.”  

However,  this conventional approach completely discounts functional or “subclinical” hypothyroidism. 

Many people are hypothyroid or have a dysfunction of their thyroid gland, but have other good compensatory physical mechanisms that may result in limited thyroid blood markers or symptoms that go undiagnosed for years. 

Subclinical hypothyroidism is defined as “a thyroid condition that is not progressed enough to be considered a hypothyroid disease on lab tests, but is a subtle disorder that can be supported nutritionally and via lifestyle to improve thyroid health and function.”

In clinical practice, “subclinical hypothyroidism” also considers: 

  • Other important thyroid blood markers (such as T3, Free T3/T4, T3/T4 Uptake, Reverse T3, thyroid antibodies)
  • Other lab markers (pointing to metabolic dysfunction and inflammation) (including: selenium, iodine, homocysteine, and underlying infections)
  • Symptoms of hypothyroidism without full blown lab markers of disease

Subclinical Hypothyroidism

Other considerations that may point to hypothyroidism or subclinical hypothyroidism (aside from TSH and T4 markers) include:

  • Low T3 markers signifying under-conversion of T4 Hormone to T3 Hormone (Note: T4 is the inactive form of thyroid hormone, T3 is the ACTIVE form. T4 must be converted to T3 before the body can use it. If T3 is low, then something may be off) 
  • Pituitary Dysfunction (Lab markers of TSH and T4 will LOOK normal, but the pituitary is causing hypothyroid symptoms)
  • High testosterone levels (PCOS is often linked to hypothyroidism)
  • Long-term history of birth-control or estrogen replacement 
  • High cortisol and/or high homocysteine levels (markers of inflammation)
  • Gluten intolerance (often undiagnosed)
  • Elevated TPO and thyroglobulin antibodies
  • Chronic infections (Lyme Disease, hepatitis C, Ebstein Barr Virus)
  • Multiple symptoms of hypothyroidism, including: sluggish metabolism, fatigue/low energy, low libido, nutrient deficiencies, low iron, low Vitamin D, constipation, easily cold

Using Functional Lab Ranges to Detect Subclinical Hypothyroidism

Functional lab ranges are narrower blood lab ranges that help patients and clinicians see patterns and progression to disease, before full blown disease occurs. They are based on studies of individuals with hypothyroidism and subclinical hypothyroidism (i.e. before full blown disease).

The functional lab ranges (i.e. “ideal”) for healthy thyroid function include these markers:

  • TSH 0.5-2.0 ug/L
  • Total T4: 6.0-12.0 ug/dL
  • Total T3: 100-180 ng/dL
  • Free T4: 1.0-1.5 ng/dL
  • Free T3: 2.5-4.0 
  • T3 Uptake: Male: 30–38% Female: 28–35%
  • Reverse T3: 9.2–24.1 ng/dL 
  • TPO and TgAB (antibodies) >4

 It’s vital to consider other markers aside from TSH or T4 alone. A full thyroid panel with these markers can help you see a clear picture into your thyroid health.  If your lab work falls outside of these ranges, it’s a signal that something may be “off.”

Types of Hypothyroidism

women stressful at work hypothyroidism

Once a “thyroid problem” has been identified, it is then important to ask the question:

What is the root cause behind my thyroid dysfunction or hypothyroidism? 

Newsflash: NOT all hypothyroidism diagnosis are directly related to the thyroid itself. 

Other causes and ties that may mask themselves or take the form of hypothyroidism blood markers include:

  • Immune dysfunction or autoimmunity
  • High cortisol/HPA Axis Dysfunction
  • Low functioning pituitary gland
  • Blood sugar dysfunction/Dysglycemia
  • Gut dysfunction
  • Environmental toxic burden
  • Chronic infection

Other Factors to Consider

If you do not have overt (conventional) hypothyroidism (a high TSH above 4.5 and low T4 below 4.87), it’s important to consider these other factors in conjunction to supporting and potentially treating the thyroid itself.

For instance, your low T3 hormones may actually be a cause from chronic stress that wreaks havoc on your pituitary gland’s ability to support a healthy thyroid. Lack of sleep, overtraining in the gym and screen exposure every night eventually catches up to your body, resulting in LOW thyroid hormone output. 

Another example: a chronic infection like hepatitis C or mercury overload may cause your liver to work super hard, demanding overwork by your thyroid and cortisol together, and suppressing TSH levels along with lower white blood cells. 

The bottom line: Hypothyroidism is not always directly related to the thyroid itself.

Sometimes it is, but often times has the ability to be improved or reversed by addressing the root cause of thyroid dysfunction. 

What to Do About It?!

There is no one-size-fits-all approach when it comes to addressing thyroid dysfunction, including hypothyroidism and subclinical hypothyroidism. 

While much of mainstream medicine has led us to believe that hypothyroidism can be “cured” with a magic pill or hormone replacement, it doesn’t work like that. 

different medication for hypothyroidism

True, medicines can help manage the condition (particularly if hypothyroidism is severe or caught in the already-progressed stage). However, depending on the nature of your condition, hormone replacement therapy may actually just be like bandaging the symptoms (rather than addressing the root cause).

The FIRST question you and your provider should ask is: Whether or not to address the thyroid directly?

As discussed previously, thyroid dysfunction can be the result of either:

  • Other underlying health problems, such as: autoimmune conditions, HPA Axis Dysfunction, nutrient deficiency, chronic infection, environmenmental triggers, immune dysfunction, or gut pathology (SIBO, yeast overgrowth, bacterial infection, dysbiosis, food intolerances, low stomach acid, etc.);
  • An actual underlying problem with the thyroid itself;
  • Or both

If your hypothyroidism is a result of something else (like chronic stress, an autoimmune condition or SIBO), it is often best to first address that pathology first, rather than solely treating the thyroid itself. In other cases, you’ll have to address the thyroid directly along with the other pathologies in order to get full resolution.

Thyroid Treatment Strategies

There are 4 primary patterns of hypothyroidism. It’s crucial to determine yours in order to avoid overtreatment or mis-treatment.

Pattern 1: Overt Hypothyroidism

Markers: High TSH (above 10), Lower T3/T4 

Strategy: Treat with replacement hormone and address other pathologies

Pattern 2: Subclinical Hypothyroidism High TSH

Markers: High TSH (above 10), BUT “Normal” T3/T4

Strategy: Treat with replacement hormone and address other pathologies

Pattern 3: Subclinical Hypothyroidism Moderate TSH

Markers: Moderate High TSH (between 2-10), possible low or normal T3/T4 

Strategy: Address other pathologies first; then re-test TSH 30-90 days later to determine whether supporting the thyroid directly (supplements or hormones) is warranted; Use family/genetic history of thyroid disease and testing for antibodies to determine risk for progression of thyroid condition 

Pattern 4: Subclinical Hypothyroidism Normal TSH, Low T3 &/or T4

Markers: Normal TSH (between 0.5-2.5), low T3 &/or T4 

Strategy: Address other pathologies first (particularly stress/cortisol, pituitary function, gut health) then re-test 60-90 days later to determine whether supporting the thyroid directly (supplements or hormones) is warranted. Use family/genetic history of thyroid disease and testing for antibodies to determine risk for progression of thyroid condition. 

Pattern 5: Elevated Antibodies, Thyroid Symptoms or Immune Dysfunction

Markers: Thyroid Antibodies (TPO, TgAB) above 4 and/or ultrasound confirmation of Hashimoto’s; Thyroid & autoimmune symptoms (like thyroiditis–attack of the thyroid gland; fatigue; metabolism imbalances; constipation; low vitamin D; low immunity; easily cold)

Strategy: Address immune system dysregulation + other pathologies first (particularly stress/cortisol, pituitary function, gut health); Helpful supplement and nutrient supports include: 

  • Supplements: Glutathione, resveratrol, Vitamin D, omega 3 fatty acids 
  • Foods: Autoimmune paleo diet protocol (avoid grains, chocolate, nuts, seeds, eggs, dairy, sugar, nightshade vegetables for 30-90 days, then slowly reintroduce to see what, if anything, you tolerate)

Umm…I’m Overwhelmed!…

The good news? You DON’T HAVE TO GO IT ALONE!

Find the Right Healthcare Provider for You

It is important to work both with a healthcare provider who understand there is “no one-size-fits-all” approach to hypothyroidism to help you feel your best. If you’re working with the right person on your “team,” this individual will look at the big picture and consider ALL factors, including:

  • Sex hormone and cortisol levels (via urine or saliva testing)
  • Environmental toxic burden (mold, toxic exposure)
  • Food intolerances/sensitivities
  • Current nutrition, exercise and sleep
  • Chronic stressors
  • Other blood markers (blood sugar balance, iron overload/deficiency, nutrient deficiencies)

More importantly, do NOT underestimate the power of lifestyle, nutrition and smart supplementation protocols to make your condition more than manageable. While the “just right” amount and type of medication can be helpful if necessary, many people can transform their “disease” almost entirely as other stressors are addressed. 

6 Essentials to Treat Hypothyroidism Naturally

1. Address Underlying Conditions

Such as:

  • Gut dysfunction
  • HPA Axis
  • Nutrient deficiencies
  • Chronic illness or infection
  • Immune dysfunction

2. Eat a Nutrient-Dense Diet

  • Including foods with iodine, selenium, iron, zinc, B12, B2 or riboflavin, vitamin C, vitamin A, vitamin D, and magnesium
  • Also, supplement, if necessary

3. Support Gut Health & Immune Function

  • Incorporate probiotics, fermented foods, prebiotics and short chain fatty acid supplementation
  • Chew your food and eat in a restful state
  • Drink water throughout the day
  • Add apple cider vinegar to water
  • Add in gut healing nutrients: bone broth, collagen, colostrum, fresh herbs, L-glutamine

4. Avoid Substances that Interfere with Proper Thyroid Function

  • Don’t overdo iodine, selenium, iron or Vitamin A/D
  • Limit goitrogenic foods (raw cruciferous veggies, sweet potatoes, strawberries) during flares
  • Limit

5. Incorporate “Anti-inflammatory” Lifestyle Factors

daily exercise helps fight hypothyroidism

  • Get your beauty sleep (7-9 hours)
  • Regular exercise (3-6 days per week); Avoid overtraining
  • Limit toxic exposures (replace plastics with stainless steel, and trade in chemical laden beauty and cleaning supplies for non-toxic hygiene, beauty and cleaning supplies)
  • Reset circadian rhythms (eating at regular times; reduce artificial light exposure)
  • Just say “no” and avoid stretching yourself too thin

6. Partner with the Right “Team”

  • Don’t settle for a healthcare provider who’s not on board for digging with you into any underlying factors 
  • Discuss nutrition and lifestyle factors with either your practitioner or a health coach and nutritionist who can support you
  • If you hit a “dead end road” in your own network look to a functional medicine practitioner who can help you navigate your thyroid health. Fortunately, there are many practitioners work virtually with clients worldwide. Additionally, some great resources include: