In the world of human health, there can be "too much of a good thing," including too many cells! Cells are marvels of human physiology. However, when cells divide uncontrollably and continue living past the time normal cells would die, that is called cancer. Rapidly dividing cells cause overcrowding and form a lump called a tumor. The tumor's presence impacts organ functionality because it takes over territory but does not perform the function of the tissue it crowds out. A healthy immune system can stop this process before it gets too far. Indeed, in our lifetimes, our bodies may head off many cancers before we ever become aware of them.
Like any organ, the cells of the thyroid can become cancerous, overgrowing to the point of disrupting functionality.
Located between the "Adam's apple" and the place where the neck meets the upper chest, the thyroid spreads in a butterfly shape over the trachea (the windpipe). Usually, it can't be felt or seen through the skin. Though hidden, the thyroid provides multiple functions for the body through the actions of the hormones it produces.
The thyroid, among other things (1, 2):
Can influence heart rate
Helps maintain internal body temperature
Manages the extraction and use of energy from food (metabolism)
Influences gut motility
Supports skin and hair integrity
The thyroid is part of a communication feedback loop with structures in the brain. Each organ releases hormones that affect the next link in the feedback loop. The top link in the feedback loop, the hypothalamus, receives information about levels of pituitary and thyroid hormones and adjusts accordingly. The pituitary gland releases thyroid-stimulating hormone (TSH), which stimulates the thyroid to produce its own hormones. The stimulated thyroid then produces hormones that affect targets in the rest of the body to maintain cellular metabolism and many other functions.
Most organs and tissues have receptors for thyroid hormones, so the health of the thyroid is vital to the overall health of the human body (2).
Triggered by TSH, the thyroid produces hormones that affect remote tissues and organs, initiating the functions listed above. One of the main thyroid hormones, thyroxine (T4), has four iodine atoms that become the activated form called triiodothyronine (T3) by removing an iodine atom. Many factors can reduce the efficiency of the conversion from T4 to T3, including environmental toxins and nutritional deficiencies.
A healthy diet is crucial for having a functioning thyroid that makes the right amount of hormones- not too much and not too little. It is noted that those suffering from autoimmune-related thyroid disorders are often deficient in many vitamins and minerals, including iodine, B vitamins, zinc, and selenium (3). Furthermore, there is evidence in the scientific literature that nutrient deficiencies can allow DNA damage (4), which often initiates cancer.
In thyroid cancer, the overgrowth of cells into cancerous tumors is due to genetic mutations in the DNA of the cells that interfere with their pre-programmed death date. Old, damaged, or unneeded cells usually undergo "cell suicide," also called "apoptosis." Yet in cancerous situations, this signal to undergo cell suicide is not received. The overgrowth of cells then forms tumors and begins pushing aside healthy thyroid tissue. Thyroid function becomes compromised, affecting the whole body. Of equal concern is the ability of cancer to break off and go to other parts of the body (metastasis).
Metastasis - A cancerous thyroid frequently infiltrates lymph nodes. Lymph nodes are located near the thyroid and provide a highway through the lymph vessels to other body parts. The lungs and many bones are also near the thyroid, presenting an opportunity for aggressive cancers to spread (5).
However, imaging technology (MRI, CT scans, ultrasound) allows small cancers to be detected. Fortunately, catching cancers at an earlier stage means treatment is more likely to be successful (5).
Symptoms of Thyroid Cancer
As a thyroid succumbs to cancer, it can behave erratically. Some may experience an under-functioning thyroid (hypothyroidism), an over-functioning thyroid (hyperthyroidism), or an erratic swinging between the two. One meta-analysis of studies did find an association between a malfunctioning thyroid and thyroid, prostate, and breast cancers (7). Researchers aren't sure if having a hyper- or hypothyroid causes thyroid cancer, so it is not listed as a risk factor.
Knowing the symptoms of hypothyroidism and hyperthyroidism is essential so early intervention and management are possible. Briefly, here are some of the more common hallmarks of these (non-cancerous) thyroid conditions:
Hypothyroid symptoms- fatigue, weight gain, cold sensitivity, dry skin, dry, thinning hair, slowed heart rate, constipation, hoarse voice, depression, memory problems, irregular or heavier than normal menstrual cycles, joint pain, and muscle weakness, aches, tenderness or stiffness.
Hyperthyroid symptoms- irregular or fast heartbeat, enlarged thyroid gland, unexplained weight loss, increased hunger, sweating, heat sensitivity, anxiety, sleep issues, fatigue, muscle weakness, thin skin, and fine, brittle hair.
Seeking a doctor in the early days of hyper- or hypothyroidism is vital. Performing blood tests, examination of the neck, and ultrasound can detect thyroid issues quickly, before the condition worsens.
Beyond symptoms of hyper- or hypothyroidism, thyroid cancer symptoms may also include (5):
A lump or small nodule in the neck under the skin
Throat and neck pain
Collar of the shirt starts feeling tight
Vocal changes, including hoarseness
Who is at Risk?
Being older, female, or having regular exposure to radiation can increase the risk of thyroid cancers (1).
Age: For females, a diagnosis of thyroid cancer seems concentrated around the ages of 40-60 years old, whereas men seem to get diagnosed later, in the 60s and 70s. Children can have thyroid cancer; it's just less likely than for people over 40 years old (8).
Sex: Females are at greater risk of thyroid cancer, up to three times more likely than men (8). There is speculation that this sex difference is due to a female's greater estrogen levels (5).
Genetics: Medullary thyroid cancer has a genetic component because it results from a hereditary mutated gene. Papillary thyroid cancer may also run in families. It is helpful to know your family medical history because there are rare genetic syndromes that increase risk of thyroid cancer and can be inherited, such as Cowden syndrome, multiple endocrine neoplasia, or familial adenomatous polyposis (5).
Radiation exposure: Radiation therapy targeted at the head or neck increases the risk of thyroid cancer (5). Additionally, exposure to nuclear weapons or power plant accidents can increase risk (8). Workers in high-risk areas who must deal directly with radiation are given equipment and education to lower exposure as much as possible, overseen by OSHA.
Tips to Maintain a Healthy Thyroid
Many tips for maintaining a healthy thyroid are the same as for maintaining good overall health, including adequate nutrition, restorative sleep, and frequent exercise.
1. Optimal nutrition is vital to a healthy body. This is why nutrition is one of the "Five Pillars of Health" mentioned in many of our articles.
It is important to be aware that nutrient deficiencies are associated with both thyroid disorders and cancer. Iodine is one important example. A lack of iodine can limit the ability of the thyroid to make thyroid hormones (9). Since the body cannot make iodine, it must be obtained from the diet. Most table salt (but not sea salts!) is iodized to help supply dietary iodine. However, there are many other sources of iodine, such as seafood.
A healthy thyroid requires a lengthy list of nutrients (3):
Vitamins A, B, C, and D
2. Control chronic inflammation - Addressing and controlling chronic inflammation is a way to increase overall health and make it harder for chronic illness to begin. Inflammation is a necessary response by the immune system to damage in the body. However, inflammation should go down once the damage is healed. In some cases, the inflammation continues past the emergency, draining the body of resources and sometimes causing pain, stiff joints, and other physical manifestations. Inflammation has been identified as either a cause or contributor to many illnesses. A simple blood test can give an idea of bodily inflammation, and TCIM doctors and practitioners are well-placed to provide strategies for reducing inflammation in a healthy and natural way.
3. Reduce inflammatory foods - Reducing foods that contribute to inflammation is one way to increase overall (and thyroid) health. Deep-fried foods, foods with many chemical preservatives and artificial colors and flavors, and high-sugar products all contribute to inflammation. Soy, wheat products (including gluten), corn, and dairy are all problematic to those with Hashimoto's thyroiditis, a disorder where the body mistakenly attacks its own thyroid. Interestingly, those same food items can also cause inflammation.
4. Attend to gut health - Maintaining gut health is vital to protecting the thyroid and many other organs. In "leaky gut," a degraded gut lining allows partially digested, large food particles into the bloodstream. The immune system sees these large food particles as foreign invaders, causing it to attack the food particles. Wheat gluten, which can cross a leaky gut, resembles an enzyme that is highly concentrated in the thyroid, and there is a high correlation of Celiac Disease (which degrades the gut lining) to autoimmune thyroid conditions (10). The suspicion is that the immune system, after attacking rogue wheat gluten particles, mistakenly attacks the thyroid because of the similarities to the physical structure of gluten. Additionally, any rogue food particles can trigger the immune system to produce inflammation.
5. Check medications - Some medications can cause "drug-induced hypothyroidism," reducing the activity and hormones of the thyroid (11). Lithium, often used to treat depression or bipolar disorder, and some medications used to prevent tumor growth are two frequent causes of lowered thyroid function.
Thyroid Cancer Prevention
All the tips on improving thyroid health are also excellent prevention strategies. To double down on thyroid cancer prevention, add the following actions.
Seek education and screening - Knowing the symptoms of thyroid conditions can help you spot an issue early. Vigilance regarding your health is essential because relaying symptoms allows a doctor to direct the investigation. It's also important to get regular physicals with the proper screenings for your symptoms. Early detection of thyroid issues gives you ample time to correct them and avoid more severe and potentially deadly, implications.
Experiencing thyroid symptoms should be a red flag to visit a doctor and get the thyroid tested. Blood is drawn for testing during our executive physicals at TCIM, and a manual examination of the thyroid on the front of the neck can be performed. Blood tests can detect high or low thyroid and pituitary hormones even if no symptoms manifest, so annual or biannual physicals are recommended. If a concern is spotted during the physical by the doctor, arrangements can be made for a thyroid ultrasound or other tests. A thyroid ultrasound can detect nodules, tumors, or other physical irregularities of the thyroid.
Maintain vitamin D levels - Keeping high vitamin D levels in the blood is vital. Vitamin D deficiency correlates very strongly with a higher risk for many different cancers (13). Discuss with your doctor the level of vitamin D you should have, as measured by blood tests. Lowering your risk for cancer could be as easy as taking a vitamin D supplement.
Ask for nutrition testing - If you are unsure if your diet meets your needs, nutrition testing is available. Nutrition testing is especially recommended for gut-related or "mystery symptoms."
The Standard of Care for Thyroid Cancer
Depending on the type of cancer identified, there may be different treatments. An oncologist will diagnose the type and stage of cancer and direct the treatment plan. The standard of care for thyroid cancer treatments includes surgery (physical removal), radioactive iodine, radiation therapy through other means, hormone therapy, chemotherapy, or some combination (1). An overview of thyroid cancer treatments is listed on the cancer.gov website.
If the thyroid is removed or rendered non-functional through other means, the patient must take thyroid medication to replace the thyroid hormones. An endocrinologist or medical doctor may become involved at this point to help determine proper thyroid hormone levels for good health. Thyroid hormones come in synthetic and natural versions, and some amount of blood testing and keeping track of symptoms helps doctors hone in on the right level for a particular patient.
Complementary Therapies for Thyroid Cancer
Integrative Medicine makes use of powerful complements to standard treatments that can reduce the effect of harsh cancer treatments and support the body as it undergoes treatment.
Detoxification, IV and ozone therapy, reducing sugar intake, and taking supplemental vitamin D are all cancer-fighting strategies described in our "Can We Prevent Cancer?" article. Please take the time to read this article, as it forms the basis for helping the body overcome challenges from both cancer and harsh cancer treatments.
The Five Pillars of Health detailed in our "How to Strengthen Your Immune System" article offers strategies for overall vibrant health. These easy-to-implement, straightforward health strategies provide the core actions to master for achieving excellent health. Interestingly, these strategies also help strengthen the immune system - something very beneficial to preventing cancer in the first place or overcoming cancer if it gets a foothold.
In addition to the therapies detailed in the articles listed above, there are other complementary therapies for addressing thyroid cancer:
Engage a nutritionist. Address nutrient deficiencies through nutritional testing and taking nutritional supplements. Nutrition is critical if receiving standard cancer treatments. Cancer treatments can deplete certain nutrients, so replacing those nutrients will contribute to a faster recovery rate (13).
Consider juicing, as it concentrates nutrients into a liquid form that is easy to absorb and can alleviate nutrient deficiencies quickly. Note, juices that address cancerous situations should all be low in sugar. Alternatively, simply blending some foods may make it easier to eat when nauseous (14). A nutritionist can explain how to incorporate juicing or blending to address specific nutrient deficiencies.
Address any gut issues quickly, especially if undergoing cancer treatments. As a side effect, some cancer treatments degrade the gut lining, causing a cascade of adverse effects on the body (15). The more the gut can be strengthened and supported, the better.
Acupuncture can help address various cancer-related issues, such as fatigue, a sluggish immune system, and cancer pain. If receiving cancer treatments, acupuncture can help alleviate nausea (16).
Consider breath exercises or mindful meditation. Breath exercises can super-oxygenate the system, helping the body to heal. There may be times during cancer treatment when breath exercises may result in headaches, but incorporating them as soon as possible will help support the body while it recovers. Mindful meditation can strengthen the ability to direct attention at unpleasant sensations (to facilitate acceptance of pain), or at pleasant sensations (to crowd out pain by focusing on pleasure).
Schedule an Appointment or Executive Physical
TCIM doctors have expertise in diagnosing complex cases of "mystery symptoms" as well as textbook diseases and disorders. If you experience the symptoms of thyroid cancer or even hyper- or hypothyroidism, please schedule an appointment with us to answer your questions and determine the best tests and screenings to help you. If you haven't had a physical lately, consider scheduling a two-step executive physical with us. The first step is a physical examination, which can help us choose additional necessary tests and screenings, such as a thyroid ultrasound. Some additional tests may require an additional visit. We can perform many screenings onsite (including a thyroid ultrasound!) with an annual executive physical. The action you take today by calling us could add precious years, and even decades, to your life.
Jonathan Vellinga, MD is an Internal Medicine practitioner with a broad interest in medicine. He graduated Summa cum laude from Weber State University in Clinical Laboratory Sciences and completed his medical degree from the Medical College of Wisconsin.
Upon graduation from medical school, he completed his Internal Medicine residency at the University of Michigan. Dr. Vellinga is board-certified with the American Board of Internal Medicine and a member of the Institute for Functional Medicine.
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