The foundation for optimizing and controlling our blood sugar is not always as simple as it seems. Most individuals are simply addressing the symptoms of blood sugar fluctuations, assuming that cutting carbohydrates or choosing low glycemic foods will solve everything. However, if you have metabolic issues, you may be merely treating the symptoms and not getting to the root cause. Complications with any part of the thyroid cascade can alter the body’s ability to metabolize, transport and manage blood sugar effectively. Thyroid function is highly correlated with the blood sugar and your capacity to optimize health. Therefore, if the metabolism is not functioning properly, blood sugar complications will likely arise.
THYROID FUNCTION & THE METABOLISM
The primary glands and organs that are responsible for blood sugar regulation can easily be altered by the thyroid system. If the thyroid system and the cascade are working properly, there should be adequate hormonal production, hormone conversion (T4 to T3), and cellular activation. With this criteria, the thyroid system will allow the body to: consume and utilize oxygen, produce energy and regulate the metabolic rate in the body’s trillions of cells. The thyroid’s global impact on almost every cell in our body has major implications for blood sugar management. Therefore, hypothyroidism or hypo-metabolic conditions can inhibit each component and essential organ related to balancing blood sugar. The major organs that will be affected are the liver, the digestive tract, the pancreas, and the adrenals.
A SLUGGISH LIVER
Remember, the liver serves to store and manufacture glucose, which regulates energy and blood sugar levels. The regulation of sugar is a delicate process that can be easily thrown off balance if the liver is overloaded and sluggish. During hypothyroidism, “There is considerable congestion of the liver, the hepatic (liver) cells secrete badly, while the canaliculi (tubular canals running between the liver cells) are compressed.” . When the liver is sluggish, glycogen (stored glucose) liberation into free glucose is slowed. Thus, the body does not get glucose for energy in a timely manner. This can lead to a state of low blood sugar, also known as hypoglycemia. The body will interpret this as a major stressor and believe that energy is needed for survival, especially for the brain and central nervous system. In response to this hypoglycemia the body will secrete cortisol and adrenaline (stress hormones) to mobilize blood sugar from the liver and glycogen reserves.
Oppositely, glucose storage to form and replenish glycogen is also slowed down. This decrease in glycogen formation will decrease glucose uptake, and also slows the insulin response. This will lead to high blood glucose in the circulation, also known as hyperglycemia. This cascade can alter the feedback to the pancreas, causing an overcompensation of insulin secretion in an attempt to rapidly bring blood sugar back down, but this can also lead to hyperinsulinemia. Unfortunately, insulin clearance in the circulation is also slowed, which can drop blood sugar levels too low and can throw the body in the opposite direction into hypoglycemia. Hypo/hyper states are problematic in so many different ways, and should be addressed immediately.
These blood sugar fluctuations will place more pressure on the already sluggish liver, which will down regulate its capacity to perform other functions. The liver is the major site for thyroid hormone conversion. Therefore, the liver will decrease T4 to T3 (T3 being the more active hormone) conversion, and also increase T4 conversion into reverse T3 (the inactive hormone). These complications will slow down the thyroid function, decrease the metabolism, and further slow down the liver. Not a cycle our body wants any part of. The liver is usually slow due to hypothyroidism.
DECREASED DIGESTIVE FUNCTION
If the metabolic rate slows due to thyroid complications the digestive system will also slow, which will lead to multiple problems for blood sugar regulation. To keep things simple, I will only touch on a few digestive concepts and will keep the emphasis on blood sugar. The main issues that arise include a decrease in stomach acid (HCL) and digestive enzymes at large. When hydrochloric acid is lacking, the stomach will struggle to properly digest and denature certain nutrients, especially proteins. Low stomach acid will also down regulate chemical messengers necessary for signaling other crucial organs that are involved in the digestive process. Digestive enzymes facilitate the breakdown of nutrients to a single molecular level, which is required for nutrients to be absorbed into the intestinal wall. Therefore, decreased levels of enzymes can inhibit nutrient absorption and eventually impact energy production. If we do not have sufficient stomach acid and enzymes the system will suffer greatly. It should be noted that excessive stress can also decrease digestive function, and it is a major contributing factor to hypothyroidism.
Digestive complications will decrease glucose absorption in the gastrointestinal (GI) tract, slow insulin secretion and clearance, and slow glucose uptake into the cell. These problems will lead to altered blood glucose levels. The possible high glucose in the bloodstream will create cross-linking with proteins, and if this persists, will lead to Advanced Glycation End-products (AGEs). The hyperglycemic state will force the pancreas to compensate by secreting more insulin, and remember insulin clearance is already slow, which will lead to hyperinsulinemia. Since glucose absorption is slow the body can also shift the other way into low circulating blood glucose, and the body can experience hypoglycemia. As mentioned above, this will create a stress response, which requires cortisol, adrenaline, and glucagon for the mobilization of blood sugar.
THE PANCREAS & PANCREATITIS
A low metabolic state will change carbohydrate/sugar metabolism and can easily overload the pancreas and lead to pancreatitis. First off, enzyme levels will be altered, due to digestive dysfunction (as mentioned above) and low body temperature (from the low metabolic state). Most enzymes are temperature sensitive, and thus hypothyroidism can change enzyme levels. The pancreas will strive to compensate, which can lead to altered serum amylase (the major carbohydrate enzyme) levels, which usually marks pancreatitis. The enzymatic changes will slow carbohydrate metabolism. Glucose absorption into the GI tract is also slowed. Furthermore, insulin and glucagon levels will be on high demand due to the sluggish liver and digestive function. All these compounding factors will cause inflammation, pancreatitis, and then lead to pancreatic insufficiency.
Pancreatic insufficiency will decrease necessary sodium bicarbonate, proteolytic enzymes, and insulin. The decreased sodium bicarbonate will not properly neutralize the acidic food matter entering the duodenum, which will contribute to metabolic acidosis. The lack of proteolytic enzymes will decrease amino acid break down and lead to amino acid deficiencies, which is what insulin is manufactured from. Finally, the decrease in insulin will wreak havoc on the blood sugar .
The body is not designed to go through extreme highs and lows when regulating blood sugar. These conditions have serious repercussions, and place a serious demand on the adrenal glands and the body. If the body is constantly undergoing hypoglycemic states the adrenal glands will have to secrete progressively more cortisol and adrenaline, to mobilize blood sugar for energy demands. When a low metabolic state is causing altered blood sugar levels and increased stress hormones, the adrenals will become over-stimulated and can atrophy. Excessive demand on the adrenals can lower cortisol levels, which can create a whole new set of problems. Interestingly, the adrenal cascade (HPA axis) and the thyroid cascade (HPT axis) both involve the hypothalamus and the pituitary, which explains how one system can affect the other and vise versa. The excessive stress will also increase estrogen, while decreasing progesterone. Progesterone assists in stimulating TPO (thyroid peroxidase), which is necessary for hormone production and activating the metabolism. Therefore, the burden that is placed on the adrenal glands and the hormonal system can make matters much worse.
HYPOTHYROIDISM & THE BLOOD SUGAR
Below is a chart outlining the possible complications that can arise. In the case of hypothyroidism or a low metabolism, the liver, the pancreas, and GI tract will be affected.
It is important to remember that each person is metabolically different and my chart above clearly doesn’t encompass every case. If anyone is dealing with these issues, identifying and changing specific nutrition and lifestyle factors can usually be of great benefit.
1. Hetoreghe, E. Thyroid Deficiency. Lecture presented to the International Surgical Congress at the New York Polyclinic School and Hospital, New York, NY. International Clinic Week. April 1914 (Brodabarnes.org)
2. Starr, M. (2005). Hypothyroidism Type 2. Columbia, MO: Mark Starr Trust.
3. Langer, S. & Scheer, J. F. (2006). Solved: The Riddle of Illness. New York, NY: McGraw-Hill.
4. Widmaier, E. P., Hershel, R., Strang, K. T. (2008). Vander’s Human Physiology: The Mechanishms of the Body Function (11th Ed.). New York, NY: McGraw Hill