Thyroid – a Neolithic Disease
(This is the first part of the presentation I made to the Physicians and Ancestral Health Meeting, January 2015)
Thyroid - that little butterfly shaped gland at the base of your front neck (under the knot of your bow-tie?) produces thyroid hormones that impact and interact with every other hormonal and metabolic system in the body. Every cell has a receptor for thyroid hormone (and vitamin D, it is said), so thyroid touches everything. Our bodies have finely tuned mechanisms for producing, storing, circulating, and activating thyroid hormones, so it’s no surprise that at times that mechanism can get a little off balance.
Under direction of the hypothalamus and pituitary in the brain – the control centers for many of our hormones – our thyroid gland produces a variety of thyroid hormones, from T1 to T4. The T4 form is the predominant form released into circulation, where it functions as a kind of “savings account.” When thyroid hormone is needed, to stimulate a vital function anywhere in the body, the T4 is converted to its T3 form, which is readily available to work. The regulation of T4 levels and T3 conversion is carefully regulated.
It just so happens that those little thyroid imbalances affect a lot of people: 9-15% of adult females, at a ratio of 8 to 1 compared to men. The great preponderance of women affected by thyroid problems is accounted for by the autoimmune nature of thyroid disease, another category of illness that affects women about eight times as much as it affects men. (Thus the rowing shell in the picture: imagine the coxswain is a man.)
I also want to suggest that most of the thyroid imbalance we see today is due to our modern foods and lifestyle. I have to wonder if it existed at all in pre-agricultural times.
Let’s start with the patient, what symptoms could indicate thyroid problems?
Physicians are well schooled in the classic clues to hypothyroidism: our patient is usually female, constipated, chilly, cold hands and feet, and always tired. Of course this woman could have other problems as well: I wonder how her menstrual cycles are, and would look to her estrogen, progesterone, and testosterone levels. If she’s exhausted but still not sleeping well, I would look further – at her adrenal glands’ function. (Our adrenal glands sit atop our kidneys and are also finely regulated by control centers in our brains: imbalances in adrenal hormone levels are usually a “control center” problem, rather than a problem with the glands themselves.)
The patient with low thyroid hormones, however, doesn’t always present with the classical symptoms. Other possible presentations include:
- Weight gain or inability to lose weight. Even subclinical hypo-thyroidism correlates fairly well with BMI and metabolic syndrome. If your thyroid (especially your T3 levels) tests are borderline (see Labs section below), but your waistline is expanding, it could mean your thyroid function is less than optimal.
- Of course, the metabolic problem could also derive from nutrient deficiencies, malabsorption, or dysbiosis – imbalance in the gut’s natural flora.
- Brain fog is another symptom of low thyroid: can’t think, focus, or remember.
- Brain fog could also be early cognitive impairment, or something as “simple” as sleep deprivation.
- Mad, sad, premenstrual blues – all of these can represent thyroid imbalance..
- Or imbalances of other hormones, nutrient deficiencies, or life challenges!
- Some of the most classic expressions of thyroid imbalance are cardiovascular, including either high or low blood pressure, irregular heart beats or more serious evidence of heart disease. Although high blood pressure is thought related to high levels of thyroid hormone, it can also be a compensation for inadequate thyroid hormone levels. Ditto with high cholesterol (especially LDL) and homocysteine levels: they could come from low thyroid levels.
- Of course, cardiovascular disease has many causes besides thyroid: “stop smoking, eat well, and stay active” could be helpful advice for many cardiac problems.
- Anemia can be due to thyroid problems
- Or, of course, nutritional deficiencies or bone marrow disease.
- Gallstones or other gall bladder disease,
- or be caused by unidentified food allergies.
- Thinning of the lateral edge of the eyebrows (Hertoghe or Queen Anne’s sign) is a classic finding, usually associated with low thyroid,
- and can also be seen in eczema, high thyroid or parathyroid levels, as well as low thyroid.
It's clear, then, that thyroid disease - because the thyroid affects every part of the body - can be a silent partner to almost any health complaint or illness.
Next part (two of three) of this article will answer the question: how to evaluate potential thyroid problem, what lab tests to order?