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Low thyroid, or hypothyroidism is more common than most people, including doctors, realize.

Do you eat like a bird and still gain weight? Feel depressed and exhausted even though you eat well and sleep enough? Do you have high cholesterol? You might have low thyroid issues.

Fortunately, it’s relatively easy to improve your thyroid levels. In fact, many cases of hypothyroidism are preventable. Here’s what you need to know.

The Prevalence of Low Thyroid

Low thyroid affects one in seven people.

Five to eight times as many women as men get diagnosed. However, that doesn’t mean it occurs in women five to eight times as often as it does in men.

Women tend to be more proactive with their health than men, so it’s likely the higher occurrence of hypothyroidism is due in part to them being tested more often

Thyroid Hormone Basics

The thyroid gland sits on the front of your neck and regulates metabolic rate.

When someone with low thyroid says, “I have a slow metabolism,” they’re right. However, it doesn’t mean they have to have a slow metabolism forever. They just need to do something about it.

The thyroid hormones include thyroid-stimulating hormone, thyroxine, triiodothyronine, reverse T3, and thyroid peroxidase. Technically, thyroid peroxidase is an antibody, not a hormone, but it should be measured along with the others.

Hormone Normal Levels
Thyroid-Stimulating Hormone (TSH) 0.45-4.21 mIU/L (optimal: 0.45-2.3 mIU/L)
Thyroxine (T4) 0.93-1.71 ng/dL
Triiodothyronine (T3) 2.3-4.2 pg/dL
Reverse T3 9.2-24.2 ng/dL
Thyroid Peroxidase (TPO) <34 IU/mL

Thyroid-stimulating hormone (TSH)

TSH is usually the first (and unfortunately, sometimes only) thyroid-related hormone doctors measure. TSH stimulates the thyroid gland to produce T3 and T4, the main thyroid hormones.

Elevated TSH indicates low thyroid production, or hypothyroidism. Low TSH indicates high thyroid function, or hyperthyroidism.

When a doctor uses only TSH to diagnose thyroid issues, he or she makes an assumption about your thyroid needs.

As an example, let’s say your co-worker drives up in a brand new, fully-loaded Tesla. Your first assumption might be that he is wealthy, or just came into a bunch of money. But if you were to look at his finances, you’d see that he’s racked up all kinds of credit card debt, sleeps on his parents couch, and has enough money after his car payment to eat ramen noodles and tuna fish three times per day.

Your assumption was wrong because you didn’t have all the facts. That’s what can happen when a doctor only looks at TSH to determine your thyroid health.

The only way to know whether your thyroid levels are optimal is to test the actual thyroid hormones, T4 and T3.

Thyroxine (T4)

T4 is the weaker of the two thyroid hormones, but it is 30–100 times more concentrated in the body than T3. So even though it isn’t as powerful, there’s so much more T4 than T3, that T4 has the greatest impact on your metabolism.

Free T4 is the T4 available for use by the body.

Triiodothyronine (T3)

T3 is the most powerful thyroid hormone. Some T3 is produced directly by the thyroid gland, and some is converted from T4.

The main difference between T3 and T4 is that T3 has three iodine molecules and T4 has four molecules. Interestingly, almost all the body’s iodine is bound to these thyroid hormones, making iodine a critical nutrient for thyroid health.

Reverse T3

As a way to remove excess T4, the body converts T4 to rT3. rT3 increases during excessive stress, chronic calorie restriction, or illness, as a way to reduce your energy expenditure.

Thyroid Peroxidase (TPO) Antibodies

Thyroid peroxidase is an enzyme necessary for proper thyroid function. When antibodies are present, it is a sign that your immune system is attacking TPO. Left unmanaged, you can destroy your own thyroid gland. The most common thyroid-related autoimmune disease is Hashimoto’s Thyroiditis.

The structure of thyroid peroxidase is similar to gluten. If you are sensitive to gluten, or have a gluten allergy, you’re at a greater risk of your immune system attacking your TPO enzymes. This is one of the many reasons we encourage you to just avoid gluten altogether.

What is Hypothyroidism?

The American Thyroid Association says that 12 percent of U.S. citizens will develop a thyroid condition during their lifetime. They also say 20 million Americans have some type of thyroid disease. If you don’t have a thyroid issue, you probably know someone who does.

Hypothyroidism is a state of low (hypo) thyroid production. As I mentioned above, many doctors determine whether a patient is hypothyroid only by testing thyroid-stimulating hormone (TSH). If TSH is high, they assume thyroid hormone production is low, and diagnose a patient with hypothyroidism.

The first stage of hypothyroidism is often called “Subclinical Hypothyroidism.”

In this stage, you have elevated TSH, but T3 and T4 are normal.

What are Symptoms of Hypothyroidism?

The best way to describe hypothyroidism is “living in slow motion.” 

Your thyroid regulates the speed of your muscle contraction, thinking, digestive system, energy and heat production, and most other metabolic processes. So when you’re hypothyroid, you really do feel like you’re living in slow motion.

Some symptoms of hypothyroidism are common with other conditions. You’ll even notice some symptoms as similar to symptoms of low testosterone or adrenal fatigue.

So, if you see yourself in the symptoms below, get your blood tested. Don’t make an assumption about your hormones based on your symptoms alone.

Symptoms of Low Thyroid (Hypothyroidism)

  • Reduced body temperature
  • Cool skin
  • Cold hands & feet
  • Reduced appetite
  • Weight gain
  • Constipation
  • Reduced muscle strength and stamina
  • Puffiness of skin, especially in the face
  • Depression
  • Rapid hair loss
  • Elevated cholesterol, and sometimes triglycerides
  • Vitamin B12 deficiency, often due to autoimmune disease
  • In women, ovaries become polycystic, which contributes to PCOS

Did you notice the bullet point about cholesterol?

I’m amazed by how many patients get a prescription for Statins to lower their cholesterol, yet their doctor never tests their thyroid.

Thyroid medication, when used for hypothyroid patients with elevated cholesterol, can consistently improve lipid levels.

I had very high cholesterol for years, along with cold hands and feet, dry skin, and a very low resting metabolic rate whenever I had it tested. It wasn’t until a few years ago that my new (at the time) doctor suggested we try thyroid medication.

Wouldn’t you know it? My thyroid numbers improved, and my cholesterol levels plummeted. No more cold hands and feet either.

For your reference, the following are symptoms of hyperthyroidism.

Symptoms of High Thyroid (Hyperthyroidism)

  • Excessive heat, sweating
  • Muscle loss
  • Insatiable appetite
  • Weight loss
  • Diarrhea
  • Hyperactivity, rapid movement, exaggerated reflexes
  • Short attention span
  • Bulging of the eyeballs (exophthalmos)
  • Increased cardiac function

What Causes Hypothyroidism?

The following are some common causes of hypothyroidism. These probably aren’t the only causes, but they are well-known contributors to hypothyroidism today.

Calorie restriction

Low-calorie diets are a very risky solution for weight loss.

They cause massive reductions in metabolic rate, break down muscle (which is also important for normal metabolic function), and are almost never effective long-term.

Your body is smart. When you chronically underfeed yourself, your metabolism slows down to accommodate the calorie reduction.

In a short period of time, you stop losing weight and have to eat even less to lose weight again.

The worst part is, your metabolic rate may not return to normal after you go off your diet. You end up eating as much as you did in the past, but you have a lower metabolic rate. As a result, many people gain back more weight than they started with before the diet.

Insufficient protein

A low-protein diet seems to have a similar effect as a low-calorie diet. Even if calorie-intake remains the same, thyroid function declines when you don’t consume enough protein.

The effect on your metabolism is just one of the many benefits of a high-protein diet.

Chronic carbohydrate restriction

Though there are many health benefits of a ketogenic diet in the short-term, long-term it can lead to hypothyroidism.

While I am a proponent of a low-carb diet, I don’t believe a ketogenic diet is wise long-term, except in those with metabolic syndrome, diabetes, certain cancers, or for high-level endurance athletes.

I especially don’t recommend a chronically low-carb diet for those with adrenal or thyroid dysfunction, or in those who train at high-intensity.

All that said, you can probably avoid the decline in thyroid by picking one day a week and eating your fill of carbs.


Gluten sensitivities and allergies reduce absorption of important micronutrients. The micronutrient deficiencies cause a heightened response from the immune system.

The structures of gluten and thyroid peroxidase are so similar that if the immune system reacts to gluten, there’s a good chance it could attack these enzymes of your thyroid as well.

There is no nutritional benefit to gluten whatsoever, so I believe people should avoid it whether they believe they have an issue with gluten or not.

Iodine deficiency

Extreme iodine deficiency causes goiter. While goiter isn’t common in the United States, it is very common throughout the world.

A normal amount of iodine, often consumed as salt, is sufficient to eliminate goiter.

However, an excessive amount of salt can also lead to thyroid problems. Those who are hypothyroid may benefit from some iodine, but not an unlimited amount.

Low selenium

Inadequate intake of selenium is also associated with low thyroid production. However, most high-quality multivitamins contain enough selenium that it shouldn’t be an issue, provided you take it every day.


Goitrogens are compounds found in some grains, as well as cruciferous vegetables like broccoli and Brussels sprouts.

These vegetables are great for detoxification and helping to remove excess estrogen from the body, but when eaten raw, an excessive amount can block the formation of T3 and T4.

When you eat them, be sure to cook them first.

Vitamin D deficiency

Low vitamin D levels are associated with autoimmune conditions. Get your vitamin D levels tested regularly, and supplement with enough vitamin D. Most people need 5,000–10,000 IU per day to maintain optimal vitamin D levels.


Chronically high cortisol reduces absorption of nutrients used in thyroid production.

Elevated cortisol also lowers TSH, reducing the production of T4 and T3. Then, low thyroid levels increase cortisol, creating a cycle of higher cortisol and lower thyroid production. Not good.

As much as I advocate the benefits of intermittent fasting, it can add unnecessary stress to someone who has low levels of resilience. Until someone corrects their T3 and T4 levels, they should avoid any form of fasting or detox diets.

In addition, oxidative stress, or excessive development of free radicals, can also cause a decrease in thyroid function. In critically ill patients, the condition is known as nonthyroidal illness syndrome (NTIS).

However, you don’t have to be critically ill to experience oxidative stress, so this could also contribute to thyroid dysfunction.

Oh, and for some reason, whenever the topic of stress comes up, a lot of people bring up coffee. Coffee is good for you, and doesn’t have a negative impact on stress levels.


Exercise probably doesn’t cause hypothyroidism, but you need to be careful about the type of exercise you engage in if you have hypothyroidism.

Low thyroid levels reduce the body’s ability to generate ATP, which is the core of what creates energy in the body. If a personal trainer doesn’t understand this, he or she might push a client beyond their exercise capacity, and make their thyroid problems worse.

Until a hypothyroid client corrects his or her thyroid levels, I would never recommend high-intensity training that pushes them to failure, exhaustion, or fatigue.

In addition to the reduced performance, low thyroid causes a transition of muscle fiber type from type I (fast twitch) to type II (slow twitch), reducing speed and strength.


Some people are born with a genetic propensity toward low thyroid production. If low thyroid runs in your family, you might avoid it through good nutrition, exercise, lifestyle, and supplement choices.

Environmental toxins

Environmental toxins such as heavy metals and polychlorinated biphenyls (PCBs) disrupt thyroid production. Some of the most common PCBs include phthalates, brominated flame retardants, and perfluorinated chemicals.

Hashimoto’s thyroiditis

Hashimoto’s is the most common cause of hypothyroidism. With Hashimoto’s, the body attacks its own thyroid tissue.

Eventually, when enough thyroid tissue is attacked, the body no longer produces thyroid hormone. While it is inconvenient, Hashimoto’s is not a death sentence, as you can take thyroid medication to regain normal levels.

Women are diagnosed far more often than men, most likely because their immune systems are more reactive.

Cancer treatment

Treatment for childhood cancer can cause hypothyroidism later in life. Radiation and medications can damage the thyroid, although symptoms may not appear until long after treatment ends. More than likely, this is a contributor to my hypothyroidism.

Radiation therapy for breast cancer can also damage the thyroid and cause hypothyroidism. If you receive radiation for breast cancer, be sure the radiology technician properly shields your neck.


Lithium is often used as a treatment for severe mood disorders, and one of its possible side effects is hypothyroidism.

How Do You Improve Thyroid Function?

Medication may be necessary to maintain optimal thyroid levels in some people. I have to use it myself.

However, there are many steps you can take to support thyroid health through lifestyle, nutrition, exercise, and supplements. In my opinion, it’s always best to do what you can through natural means, and if that doesn’t work, only then opt for medication.

Although many people go right to medication, there are also others who refuse to use pharmaceuticals and instead suffer with symptoms year after year. It doesn’t need to be that way. There is a time and place for medication, even for those who want to be as “all natural” as possible.

Eat Some Carbohydrates

Low-carbohydrate diets provide a plethora of health benefits. For most people, they’re safe and effective for long-term health and weight management. With about 70% of the population dealing with insulin resistance, diabetes, and/or metabolic syndrome, there’s no more effective way of eating than a low-carb diet.

As good as it is, some people may notice that it isn’t as effective after a while, and even begin developing symptoms of hypothyroidism. Low-carb diets have been shown to decrease thyroid production.

A simple fix is to eat a large amount of carbs once a week.

Once someone has improved his or her insulin sensitivity and maintained an ideal body weight for a year or more, it may be wise to eat a modest level of carbohydrates. I won’t get into it here, but I do believe the best time to eat them is at dinner when you do. Definitely not at breakfast.

Go gluten-free

When it comes to gluten, you can’t be “mostly gluten-free” to protect your thyroid. You’re either in or you’re out.

This is especially true for those with autoimmune conditions like Hashimoto’s disease. The smallest amount can trigger an immune response, and some experts believe the response can last weeks to months.

Follow a good weight training program

I encourage those with thyroid and/or adrenal dysfunction to use lower reps, and heavier weights a few times per week to build muscle, and slowly get their muscles to begin functioning better. Actually, the two forms of exercise I recommend are heavy weight training, and walking.

I do not recommend intense cardio and definitely no high-intensity interval training or metabolic conditioning.

Get enough sleep every night

Sufficient, quality sleep supports all of your hormones. Your body produces hormones in certain rhythms throughout the 24-hour cycle of a day. By getting regular, quality sleep, you help your body maintain a normal circadian rhythm, which helps it produce hormones on an expected cycle.

Use some of these supplements that support thyroid function

Black Cumin

In patients with Hashimoto’s thyroiditis, a daily dose of 2 grams per day of Black Cumin (also known as Fennel Flower or Nigella sativa) lowered thyroid peroxidase and TSH, showing that it improved the markers of the autoimmune condition while improving thyroid function.

N-Acetyl L-Carnitine

Thyroid hormone increases the excretion of l-carnitine, an amino acid important for fat metabolism.

Hypothyroid patients who begin using thyroid medication may experience a deficiency of l-carnitine, contributing to the feelings of fatigue.

A 12-week study of hypothyroid patients on levothyroxine (i.e. Synthroid), showed that those who supplemented with 1980 mg of n-acetyl l-carnitine per day eliminated feelings of fatigue.

Coenzyme Q10

Although hypothyroidism leads to mitochondrial dysfunction, supplementing with other nutrients such as Coenzyme Q10, NADH, and alpha-lipoic acid have not shown consistent improvements in fatigue-related symptoms. That said, thyroid medication may deplete Coenzyme Q10 levels, so it may be wise to supplement with it.


Cysteine is an amino acid. You’ll find it in supplements as l-cysteine, l-cysteine HCl, and n-acetylcysteine. L-cysteine is used to build glutathione, the body’s primary antioxidant. In fact, if cysteine levels are low, you can’t make this incredibly important antioxidant.

As mentioned above, oxidative stress contributes to hypothyroidism. Supplementation with cysteine has been shown to lessen the drop in thyroid hormones associated with oxidative stress.


You probably don’t eat the pituitary, thyroid, adrenals, or any other glands of beef, pork, lamb, or other meats very often.

It’s only been in recent history that the average person eats just the muscle tissue of meat and poultry and tosses the rest.

Like the glands in humans, the glands of animals provide the building blocks of important hormones. Remember, the pituitary builds and secretes TSH. The thyroid produces and releases T4 and T3. The adrenal glands produce and release cortisol, which is necessary for proper thyroid function.

The manufacturing of glandular supplements removes the actual hormones, but the building blocks for those hormones are often found in the gland itself. The theory is, if you need to support your adrenals, eat or take adrenal gland. If you need to support your thyroid, eat or take thyroid gland.

If you look back through history, the consumption of glands to promote health was a normal thing. In today’s pharmaceutical world, glandulars are often poo-pooed by conventional healthcare practitioners. You can find pituitary, thyroid, and adrenal extracts in supplemental form. They might be worth trying in collaboration with a nutrition or healthcare practitioner.


Adaptogens are herbs and extracts that help maintain normal cortisol levels. They help to bring hormones and metabolism back into balance, so if cortisol is high, they help bring it down. If cortisol levels are too low, adaptogens can help bring levels back up.

Some of the most powerful and popular adaptogens include ashwagandha, astragalus root, cordyceps mushroom, eleutherococcus senticosus, holy basil, licorice root, Panax ginseng, rhodiola rosea, and tribulus terrestris.*

Other Antioxidants and Essential Oils

Because oxidative stress does affect thyroid function, other antioxidants may help with squelching free radicals, reducing their negative effect on thyroid function.

Aside from eating antioxidant-rich foods (i.e. blueberries, goji berries, dark chocolate), essential oils are also powerful antioxidants. Because there are so many antioxidants, I don’t expect to see research anytime soon on this. That said, I believe it’s wise to complement your diet with a variety of antioxidant sources, not just for thyroid health, but for your health in general.

Talk to your doctor about medication

Synthroid and Armor Thyroid are the two most common thyroid medications. Synthroid is the brand name of levothyroxine, which is a synthetic form of T4. It’s also sold under the brand names of Tirosint, Levoxyl, Levothroid, Unithroid, and Novothyrox.

Taking T4 obviously increases T4 levels. Additionally, most people can convert T4 to T3, so taking T4 alone may help correct T4 and T3 levels. However, some doctors find their patients do not see an improvement of T3 while taking levothyroxine. In these cases, the patients probably have an issue converting T4 to T3, so this medication may not be the most effective.

Armor Thyroid is created with desiccated thyroid or thyroid extract. It’s kind of like taking a glandular, except that it’s manufactured to standardize the thyroid hormone in each tablet.

Some argue that this makes it a superior form thyroid medication. I use Armor myself. On the other hand, it’s possible that in those with autoimmune issues, they may attack this medication, just like their own thyroid, making the medication ineffective.

From the research I’ve read on the two options, I don’t know that one is significantly better than the other.

Both medications improve metabolic rate, heart rate, body weight and fluid levels. That said, a good physician will consider changes in a patient’s lab work, as well as changes in how they feel. It may be that one type of medication helps someone feel better than another, even though both may help the thyroid levels improve.

Even when thyroid levels are brought back to normal with medication, many people still experience fatigue, muscle aches, depressed mood, decreased memory, psychological distress, and cognitive dysfunction. This is why I feel it’s prudent to still use thyroid-supporting supplements and make healthy lifestyle, nutrition, and exercise choices.

Some research has been done to look at the use of stem cells for rebuilding thyroid tissue. This would be especially beneficial for those who have to have their thyroid removed.

One final note: Your thyroid hormones act in partnership with many other hormones in the body.

Sometimes, low thyroid levels aren’t the issue. It’s something else. In fact, adrenal fatigue and hypothyroidism often go hand in hand.

An experienced holistic doctor looks at all possible causes of someone’s symptoms before prescribing medication. Your job as a consumer is to select the best practitioner.


Keep the conversation going.

Leave a comment, ask a question, or see what others are talking about in the Life Time Health Facebook group.

The Life Time Health Team

Thoughts to share?


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