Did you know that your thyroid affects literally everything in your body? Your weight—your hair; energy and fatigue; mental clarity. In fact, your thyroid controls how fast you burn energy and how fast you heal. It affects heart health, joint pain, and much more. Actually, the list is quite long. And it is LIFE long.

This very prevalent problem really deserves some explanation. Allow me to share some important insights I’ve learned just in the past 3 years about low thyroid function. In this article I’ll spell out what your thyroid hormones do for you and what the signs and symptoms of low thyroid function are. I’ll also explain how it is that several chronic health conditions can be improved by treating low thyroid hormone function, which you probably didn’t know were even related.

Thyroid hormones affect many organs and systems

The thyroid gland sits just in front of your windpipe in your lower neck region. It produces primarily two active hormones: T4 (thyroxine) and T3 (triiodothyronine). Let’s look at what these thyroid hormones do in your body.

Thyroid hormones determine the metabolic activity of just about every cell in your body. Thyroid hormone:

Increases blood flow, heart rate, energy production, and metabolismSpeeds up thinking, intestinal motility, thirst, and urinationLowers blood pressure (when optimal levels are achieved)Decreases LDL (“bad”) and total cholesterol levels and improves HDL (“good”) cholesterolImproves your immune defenses against various infections and cancer[i]Improves other endocrine gland function so they can more readily produce their respective hormones, including cortisol and the sex hormonesIs a critical driver of nutrients into each cell as well as of waste product removal from each cell including old, defective enzymes.

Contrariwise, if your thyroid hormones are under-functioning then there are a number of organ systems that will also under-function. Is this something you should be concerned with? Well, consider that low thyroid hormone function is estimated to affect nearly 50 percent of American adults, according to the clinical experience of a prominent group of European endocrinologists, Dr. Broda Barnes and several generations of the Hertoghe family of endocrine physicians from Belgium. That’s why you really need to know the key symptoms and signs to look for—and that this is treatable.

Symptoms caused by low thyroid hormone function 

Low thyroid hormone has the potential to cause illness in any body tissue or organ. When your metabolic rate slows, many indicators will be subtle. However, if low thyroid state remains, later findings will arise. Early and later indicators are listed here together:

Feeling tired in daytime when sitting or at restUnwanted weight gain; morning puffy face/swollen eyelids; water retentionSensitivity to cold; hands and feet often coldConstipation, abdominal bloating or colitis symptomsCardiovascular effects: high blood pressure, high cholesterolMemory/concentration impairment; confusion, depression, dementiaDepressed mood or anxiety upon wakingMenstrual disorders (excessive bleeding or painful menses)Dry or slow-growing hair or nails/excessive hair loss; acne, eczema, psoriasisHoarse voice, slowed speechStiff or painful joints; rheumatoid or osteoarthritis; carpal tunnel syndromeNight time muscle cramps / burning or tingling/ bradycardia (slow rate)Hypoglycemia (low blood sugar)Frequent colds, sore throats, ear aches, or other infectionsEndometriosis, infertility, miscarriagesHeavy menstrual bleeding, infertility; increased risk of miscarriages, premature deliveries and stillbirths.

Are you feeling low in thyroid (metabolism) hormone, but your lab tests are “normal”?

You probably know that the amount of your thyroid hormones are accurately measurable with these standard blood tests: TSH, T3, and T4. However, these cannot measure how well your thyroid hormones work in your thyroid-sensitive tissues (i.e. their function). This may explain the disconnect for many of you who have symptoms of low thyroid function, yet your thyroid blood tests are “fine.”

In my next post, I will share more about low thyroid function: why it is being so underdiagnosed, and how easy the treatment can be.

To feel good with hormone balance,

Michael Cutler, M.D.