Are you experiencing fatigue, hair loss, low libido or sexual dysfunction, constipation, cold hands and feet, cholesterol problems, or difficulty losing weight? You might have a thyroid problem. Your thyroid gland is important since it produces hormones that signal all the cells in your body to create energy and to grow when needed. They are responsible for stimulating energy production and determine how many calories you burn every day. In this article I will be writing about the importance of a healthy thyroid, how it works, and what symptoms you might experience when it is not working properly.
Your metabolism engine
The thyroid is like the engine in your car. It dictates how fast or slow you are moving. In your body, it dedicates how many calories you are burning and how fast your body produces energy. If your engine slows down, your car will slow down. In a similar way, if your thyroid slows down, your metabolism slows down and you might feel tired. According to the American Thyroid Association, low function of the thyroid leads to lower metabolism, also called basal metabolic rate (BMR).  Over the years, many people reported to me that they were slowly gaining weight with no obvious reason for that. Their diet and level of activity was the same. Some even complained that they were working out several times a week and had difficulty losing weight. These could all be symptoms of thyroid dysfunction. Other symptoms of hypothyroidism are:
Dry skin, fatigue, cold sensitivity, constipation and muscle cramps 
Increase in cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides. 
Subclinical Hypothyroidism was found to be associated with ischemic heart disease in people of 65 years and younger. 
Lower sexual function, Depression. 
Slow bowel movement or constipation. 
Dysfunction of sugar metabolism as was noticed by higher HbA1C. 
Low thyroid function (hypothyroidism) was found to be associated with hair loss. 
How does your thyroid gland work?
The thyroid stimulates each cell in your body through the thyroid hormones, called T3 and T4. These hormones are released from your thyroid and are circulated in the blood to reach your cells. Most of the T3 and T4 are bound to proteins and are inactive, with the exception of free T3 and T4, which are able to connect to the receptor on each cell and stimulate the cells to function and produce energy. Among both hormones, T3 is highly active, however, it is present in significantly lower amounts than T4. To keep stimulating your metabolism and for proper function, the body requires more T3. Therefore, T4 is converted to T3 in organs such as the liver, kidney, brain, and muscles. 
What activates your thyroid gland?
The thyroid gland is activated by the Thyroid Stimulating Hormone (TSH). The hypothalamus secrets thyrotrophin-release hormone (TRH) which stimulates the pituitary to secrete TSH. When your pituitary detects that the thyroid gland is producing too little thyroid hormone, the pituitary produces more TSH, which stimulates the thyroid to produce more thyroid hormone. Deficiency of thyroid hormone is associated with dry skin, poor memory, slow thinking, depression, cognitive impairment, muscle weakness, fatigue, muscle cramps, cold intolerance, puffy eyes, constipation, and hoarseness. Some studies also reported an association with higher risk for cardiovascular diseases as measured by increased serum levels of total cholesterol and low-density lipoprotein (LDL) cholesterol and reduced high-density lipoprotein cholesterol. 
Why are most people with low thyroid function undiagnosed?
The reason for that is simple. When complaining of thyroid symptoms, such as fatigue, weight gain, constipation, or even the presence of high cholesterol in your labs, most doctors will only test for the thyroid stimulating hormone (TSH). This measures how much your anterior pituitary is trying to stimulate your thyroid to work. There is an assumption within the medical community that measuring how much the thyroid is stimulated is enough to determine if it is working. Unfortunately, that is not always the case. A study published at the Journal of Nutritional & Environmental Medicine showed that in most cases, thyroid symptoms did not correlate with levels of TSH.  This means that if you went to your doctor and complained of fatigue, constipation, cold hands or feet, or weight gain, measuring your TSH levels are just the ‘tip of the iceberg.’ They won’t show the whole picture. This is exactly why I wrote this article: So many people are misdiagnosed and they do not know it. Their doctor looks at their labs and sends them home, while they still suffer from symptoms of low thyroid function. In the next article, I will show you what to look for to make sure that your thyroid is working properly.
Thyroid & Weight. American Thyroid Association. https://www.thyroid.org/wp-content/uploads/patients/brochures/Thyroid_and_Weight.pdf. Accessed 2016.
Garber JR, Cobin RH, Gharib H et al. Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association. Thyroid 2012; 22: 1200–35.
Asvold BO, Vatten LJ, Nilsen TI, Bjoro T. The association between TSH within the reference range and serum lipid concentrations in a populationbased study. The HUNT Study. Eur J Endocrinol 2007; 156: 181–6.
Razvi S, Shakoor A, Vanderpump M et al. The influence of age on the relationship between subclinical hypothyroidism and ischemic heart disease: a metaanalysis. J Clin Endocrinol Metab 2008; 93: 2998–3007
Krysiak, R., Drosdzol-Cop, A., Skrzypulec-Plinta, V., & Okopien, B. (2015). Sexual function and depressive symptoms in young women with thyroid autoimmunity and subclinical hypothyroidism. Clinical Endocrinology, 84(6), 925-931. doi:10.1111/cen.12956.
Bassotti G, Pagliacci MC, Nicoletti I, Pelli MA, Morelli. Intestinal pseudoobstruction secondary to hypothyroidism. Importance of small bowel manometry. A J Clin Gastroenterol. 1992 Jan; 14(1):56-8.
Makadia, M. G. (2017). Study of Glycated Haemoglobin (HbA1c) In Non-Diabetic Subjects with Subclinical Hypothyroidism. Journal Of Clinical And Diagnostic Research. doi:10.7860/jcdr/2017/22600.9479
Sarris, J., & Wardle, J. (2014). Clinical naturopathy: an evidence-based guide to practice. Chatswood, N.S.W.: Elsevier Australia.
Mcdermott, M. T. (2001). Subclinical Hypothyroidism Is Mild Thyroid Failure and Should be Treated. Journal of Clinical Endocrinology & Metabolism, 86(10), 4585-4590. doi:10.1210/jc.86.10.4585
Douglas J. Fort, Sigmund Degitz, Joseph Tietge, Leslie W. Touart. (2007) The Hypothalamic-Pituitary-Thyroid (HPT) Axis in Frogs and Its Role in Frog Development and Reproduction. Critical Reviews in Toxicology 37:1-2, pages 117-161.