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Hypothyroidism (Underactive Thyroid) Symptoms, Causes & Best Diet
October 14, 2022
Almost 5 percent of the U.S. population over the age of 12 has some form of hypothyroidism (an underactive thyroid). Some estimates suggest up to 40 percent of the population suffers from at least some level of underactive thyroid.
Women — especially older women — are the most susceptible group for developing hypothyroidism. People who are elderly or who have other existing autoimmune diseases — like type 1 diabetes, rheumatoid arthritis and celiac disease, for example — are also at a higher risk.
Changes to your metabolism, heart function, digestion, energy, appetite, sleep or mood … even the growth of your hair, skin and nails … can all be caused by hypothyroidism.
However, a hypothyroidism diagnosis is not a death sentence! There are many ways to treat hypothyroidism naturally through a hypothyroidism diet plan and other natural remedies. Find out how to start your health transformation journey below.
What Is Hypothyroidism?
Hypothyroidism is a condition in which the thyroid gland is underactive and doesn’t properly make or release thyroid hormones. The thyroid gland normally releases many crucial hormones that travel through the bloodstream to reach receptors found throughout the whole body. So a disturbance in thyroid function can cause widespread, noticeable health problems.
The thyroid is a small gland located on the base of your neck, sometimes described as butterfly-shaped. Meanwhile, at the base of the brain sits the pituitary gland, which secretes the thyroid-stimulating hormone (TSH). TSH makes the thyroid produce and release thyroxine, the main thyroid hormone.
The difference between hyperthyroidism vs hypothyroidism involves thyroid activity. While hypothyroidism mean an underactive thyroid, hyperthyroidism occurs when the thyroid gland becomes overactive.
The thyroid is considered a “master gland.” In addition to producing crucial hormones, it helps control the process of turning nutrients from food into usable energy on which the body runs. Because the thyroid plays such a major part in your metabolism, dysfunction can affect almost every part of the body, including your energy levels and ability to burn calories.
Key hormones produced by the thyroid also help the liver break down cholesterol that circulates through the bloodstream. The thyroid can also stimulate enzymes that are needed to control triglyceride fat levels; this is why changes in thyroid function cause lead to heart problems.
Other noticeable effects of hypothyroidism include moodiness and a sluggish metabolism. Essentially, when your thyroid is underactive, your metabolism will slow down, which might mean you always feel tired or struggle to keep off weight.
Your mood is especially susceptible to changes in hormone levels, so some people with hypothyroidism deal with depression, anxiety, trouble getting good sleep and low immunity. The thyroid gland helps regulate chemical messengers called neurotransmitters, which control your emotions and nerve signaling. This is the reason an out-of-balance thyroid can mean drastic emotional changes at times.
Some of the most common warning signs of hypothyroidism include:
- Depression and anxiety
- Weight gain
- Goiter (nodules at the base of the neck, sometimes accompanied by tightness in the throat, coughing or swelling)
- Feeling cold
- Muscle aches and tenderness
- Kidney problems
- Stiffness and swelling in the joints
- Hair loss
- Rough, cracked skin
- Trouble breathing
- Changes in the menstrual cycle
- More frequent cold or flu due to low immune function
To find out if you have hypothyroidism, your doctor will run blood tests to check for levels of the hormones known as T4 (thyroxine) and TSH (thyroid-stimulating hormone). Hypothyroidism is diagnosed in your thyroid test when TSH is high. Sometimes, TSH can be high, but the thyroid is still producing enough hormones. This condition is referred to as subclinical (or mild) hypothyroidism.
Mild hypothyroidism is usually the early stage. It can progress to hypothyroidism if a hypothyroidism diet isn’t adopted and lifestyle changes aren’t made. When the condition isn’t corrected, more severe autoimmune reactions can occur — this can cause worsened problems like impaired brain function, infertility, unhealthy pregnancy, obesity, heart complications and joint pain.
Another symptom to be aware of is thyroid nodules, a buildup of cells within the thyroid, creating an abnormal lump. Most thyroid nodules aren’t dangerous. But some of them become cancerous over time. If your physician suspects you have thyroid nodules, he or she should have them evaluated to check for cancer cells.
For patients with thyroid cancers, a common conventional treatment method is known as radioiodine, or radioactive iodine. Because the thyroid absorbs most of your body’s iron content, this concentrated radiation is supposed to successfully kill most of the diseased thyroid cells without damaging cells throughout the rest of the body.
Complications of an Underactive Thyroid
In some cases, people with an extremely underactive thyroid may fall into what is known as a myxedema coma, characterized by declining mental status, hypothermia and the slowing of many internal organs. If you or someone you know has severe thyroid problems and begins to show major lethargy or stupor, seek emergency medical attention at once.
Myxedema comas are rare and occur most often in the elderly and women, especially in the winter months. Generally, it is the result of undiagnosed and/or untreated hypothyroidism and can be fatal if left untreated.
Hypothyroidism is very prevalent in kidney disease patients, in turns out. In a Current Opinion in Endocrinology, Diabetes and Obesity study, evidence suggested that hypothyroidism was a risk factor for chronic kidney disease (CKD), CKD progression and even higher death risk in kidney disease.
Related: Why Am I Always Cold? Causes + How to Fix It
1. Inflammatory disorders of the thyroid
The most common cause of hypothyroidism in developed nations is a condition called Hashimoto’s thyroiditis. This is an autoimmune endocrine disorder that occurs when the thyroid becomes inflamed. When someone has Hashimoto’s, their own body essentially begins to attack itself by producing antibodies that try to destroy the thyroid gland.
Why does this happen? The immune system mistakenly thinks that the thyroid cells are not a part of the body, so it tries to remove them before they can cause damage and illness. The problem is that this causes widespread inflammation, which can result in many different problems. According to Dr. Datis Kharrazian, 90 percent of people with hypothyroidism have Hashimoto’s that inflames the thyroid gland over time, but this isn’t the only cause of hypothyroidism.
2. Poor diet (especially one lacking in iodine and selenium)
A diet low in nutrient-rich foods, especially in iodine and selenium (which are trace minerals crucial for thyroid function), increases the risk for hypothyroid disorders. The thyroid gland needs both selenium and iodine to produce adequate levels of thyroid hormones.
These nutrients also play other protective roles in the body. For example, severe selenium deficiency increases the incidence of thyroiditis because it stops activity of a very powerful antioxidant known as glutathione, which normally controls inflammation and fights oxidative stress. Getting on track with a hypothyroidism diet ensures that you get the appropriate amounts of selenium and iodine in your diet.
3. Hormone imbalances
In some rare cases, because the pituitary gland makes a hormone called thyroid-stimulating hormone (TSH) — which controls the levels of hormones being pumped out of the thyroid — a problem with the pituitary gland can cause changes to thyroid function.
4. Gut inflammation (leaky gut syndrome)
An unhealthy gut environment can contribute to nutrient deficiencies and raise autoimmune activity in the body. Food sensitivities or allergies, including those to gluten and dairy, can trigger gut inflammation. Other causes of a damaged gut are high stress levels, toxin overload from diet and the environment and bacterial imbalances.
When leaky gut occurs, small particles that are normally trapped inside the gut start to leak out into the bloodstream through tiny openings in the gut lining, which creates an autoimmune cascade and a series of negative symptoms.
Although it’s not very common, newborns are sometimes born with a dysfunction of the thyroid gland, a genetic condition called congenital hypothyroidism. Some evidence shows that people are more likely to develop hypothyroidism if they have a close family member with an autoimmune disease.
But according to the National Institute of Health (NIH), the likelihood of congenital hypothyroidism is very low and only about 1 out of every 4,000 newborns is born with a thyroid disorder.
During or following pregnancy, although it’s not exactly known why, some women begin to produce very high levels of thyroid hormones, followed by a very rapid decline. This condition is known as postpartum thyroiditis. The symptoms often disappear within 12–18 months but can also lead to permanent hypothyroidism.
7. Interactions of certain medications
Specific medications seem to lead frequently to the development of underactive thyroid. The most common of these include drugs to treat cancer, heart problems and certain psychiatric conditions.
8. High levels of emotional stress
Stress impacts hormones and is known to worsen inflammation. Stress can raise levels of cortisol and adrenaline, which disturbs neurotransmitter function and worsens symptoms of thyroid disease. These include low energy levels, poor mood, low concentration, disturbed appetite and weight gain and the inability to get restful sleep.
9. Inactivity and lack of exercise
Exercise and a healthy diet are important for controlling chronic stress and managing hormone-related neurological function. Research shows that people who regularly exercise usually get better sleep, deal with stress better and more often maintain a healthier weight, all of which reduce some of the biggest risk factors and symptoms associated with hypothyroidism.
How is hyp0thyroidism diagnosed? Usually a physical exam along with a review of your medical history by a health professional can help determine if you have hypothyroidism.
The health professional will look for such symptoms as eye changes, overactive reflexes, a tremor in the fingers when extended, and even warm, sweaty skin. Also, the thyroid gland will also be observed while swallowing to determine if it’s enlarged, tender or even bumpy. Your pulse may also be rapid or irregular, another potential symptom.
Blood tests are also take that measure thyroxine and thyroid-stimulating hormone. An overactive thyroid typically reveals high levels of thyroxine and very low levels of thyroid-stimulating hormone.
If these blood tests show potential hypothyroidism, a radioiodine update test is usually recommended. It will help determine if your thyroid is overproducing thyroxine, or even thyroiditis. A thyroid scan and ultrasound may also be prescribed.
Conventional treatment options for hypothyroidism are most pharmaceutical. Antithyroid drugs methimazole (Tapazole) or propylthiouracil (PTU) are commonly prescribed, as these medications help block your thyroid’s ability to make hormones.
Radioactive iodine is also sometimes prescribed. An oral medication that is absorbed by your overactive thyroid cells, it damages these cells and reduced the size of your thyroid while thyroid hormone levels slowly decrease. This can functionally eliminate the thyroid and thus stop hypothyroidism. If you receive this treatment, you will need to take thyroid hormone drugs in order to maintain normal hormone levels.
Beta blockers can also be used to stop the impact of thyroid hormones on the body and help control symptoms. Because they don’t alter hormone levels, they’re often paired with other options to treat hypothyroidism.
Removing your thyroid though surgery, or a thyroidectomy, is also an option. It would also mean thyroid supplements for the rest of your life to keep hormone levels normal.
The risks of side effects to these treatments is significant, so it’s critical to talk to your healthcare provider and keep a close eye on your symptoms. Meanwhile, following a hypothyroidism diet can also help to alleviate symptoms.
Hypothyroidism Diet Plan
1. Best foods
What foods are good for an underactive thyroid? Here are the top foods for a hypothyroidism diet to start the healing process:
- Wild-caught fish: It provides the omega-3 fatty acids EPA and DHA, essential for hormone balance and thyroid function.
- Coconut oil: This provides medium-chain fatty acids in the form of caprylic acid, lauric acid and capric acid, which support a healthy metabolism, increase energy and fight fatigue.
- Seaweed: Good seaweeds are some of the best natural sources of iodine and help prevent deficiencies that disturb thyroid function.
- Probiotic-rich foods: These include kefir (a fermented dairy product), organic goat’s milk yogurt, kimchi, kombucha, natto, sauerkraut and other fermented veggies.
- Sprouted seeds: Flax, hemp and chia seeds provide ALA, a type of omega-3 fat that’s critical for proper hormonal balance and thyroid function.
- Clean water: Water helps with hydration and digestive function while preventing fatigue and moodiness. For prevention of constipation, low energy and sugar cravings, drink at least eight ounces every two hours.
- High-fiber foods: People with hypothyroidism may have digestive difficulties, so aim for 30–40 grams of fiber daily. Not only does a high-fiber diet help with digestive health, it also improves heart health, balances blood sugar levels and supports a healthy weight by making you feel fuller.
- Bone broth: Beef and chicken bone broth contain the amino acids L-proline and L-glycine, which can help repair the digestive lining and improve hypothyroidism.
- Fruits and vegetables: These are high in vitamins, minerals and antioxidants that are necessary for combating free-radical damage and lowering inflammation. They are nutrient-dense and should make up a large portion of a healthy diet since they support digestive health, brain function, heart health, hormone balance and a healthy weight.
2. Worst foods
These are foods that should not appear in your hypothyroidism diet:
- Goitrogen foods: People with hypothyroidism may want to stay away from eating large amounts of raw Brassica vegetables like broccoli, cauliflower, cabbage, kale, soy and Brussels sprouts. These vegetables might impact thyroid function because they contain goitrogens, molecules which impair thyroid perioxidase.
- Tap water: Most tap water contains fluorine (an endocrine disruptor) and chlorine that inhibit iodine absorption.
- Gluten: Many people with thyroid issues are also sensitive to gluten or have celiac disease, an autoimmune disease that results in an allergy to gluten. Gluten is found in all wheat, rye and barley products. Carefully check ingredient labels to avoid hidden gluten that is lurking in many packaged foods.
- Conventional dairy: Like gluten, dairy can be especially problematic for the thyroid, triggering reactions that raise inflammatory responses. Avoid conventional cow’s milk dairy products that are not organic and have been pasteurized. Consumption of organic, raw goat’s milk or organic A2 cow’s milk is a better choice.
- Sugar: Sugar can disrupt the hormone balance necessary for metabolism. People with thyroid issues have a difficult time losing weight. Because the thyroid is a key gland for hormonal balance and metabolism, it’s best to avoid sugar as it can contribute to hormonal disturbances, fatigue, mood changes, worsened depression and weight gain.
- Refined flour products: Any food made with refined carbohydrates, like enriched wheat flour, for example, negatively impacts hormone levels and can contribute to weight gain.
3. Consider taking these supplements
Ashwagandha (500 milligrams daily)
Ashwagandha is an adaptogen herb that helps the body respond to stress, keeping hormone levels better in balance. Adaptogens helps lower cortisol and balance T4 levels. In fact, in clinical trials, supplementing with ashwagandha for eight weeks essentially worked as thyroxine treatment, helping hypothyroidism patients significantly increase thyroxine hormone levels and thus reduce the severity of the disorder. Also, try other adaptogen herbs like rhodiola, licorice root, ginseng and holy basil, which have similar benefits.
Iodine (150–300 micrograms daily)
Studies show that even small amounts of supplementary iodine (250 micrograms) cause slight but significant changes in thyroid hormone function in predisposed individuals. A diet rich in whole foods that contain iodine — including fish, sea vegetables, eggs, raw dairy and seaweed — can help prevent deficiency.
Iodine supplements should not be taken with Hashimoto’s disease because getting too much iodine over the longterm increases the risk of developing an overactive thyroid. While it’s nearly impossible to get too much from eating a variety of healthy foods alone, sometimes people taking supplements or eating very high amounts of dried algae and seaweed can exceed the recommended upper limit of 500 milligrams per day.
Selenium (200 micrograms daily)
The thyroid is the organ with the highest selenium content in the whole body. Selenium is necessary for the production of the T3 thyroid hormone and can reduce autoimmune affects. In patients with Hashimoto’s disease and in pregnant women with thyroid disturbances, selenium supplementation decreases anti-thyroid antibody levels and improves the structure of the thyroid gland.
Because it helps balance hormone levels, selenium can lower the risk for experiencing thyroid disorder during pregnancy (postpartum thyroiditis) and afterward. Other studies have shown that when selenium deficiency is resolved through supplementation, patients experience on average 40 percent reduction in thyroid antibodies compared to a 10 percent increase when given a placebo.
L-tyrosine (500 milligrams twice daily)
An amino acid used in the synthesis of thyroid hormones, thyroxin (T4) is naturally produced from the iodination of tyrosine, a nonessential amino acid obtained both from protein-containing dietary sources and through the body making some itself.
Supplementing with L-tyrosine has been shown to improve sleep deprivation and can help combat fatigue and a poor mood by improving alertness and neurotransmitter function. One reason L-tyrosine is beneficial in healing thyroid symptoms is because it plays a role in the production of melatonin, dopamine and/or norepinephrine, which are our natural “feel good” hormones.
Fish oil (1,000 milligrams daily)
Essential fatty acids found in fish oil are critical for brain and thyroid function. DHA and EPA omega-3s found in fish oil are associated with a lower risk for thyroid symptoms, including anxiety, depression, high cholesterol, inflammatory bowel disease, arthritis, diabetes, a weakened immune system and heightened autoimmune disease. Omega-3 fish oil supplements can also help balance levels of omega-6s in the diet, which is important for ongoing health.
Vitamin B-Complex (one B-complex capsule daily)
Vitamin B12 and thiamine are important for neurologic function and hormonal balance. Research shows that supplementing with thiamine can help combat symptoms of autoimmune disease, including chronic fatigue. In one clinical study, when patients with Hashimoto’s were given 600 milligrams per day of thiamine, the majority experienced complete regression of fatigue within a few hours or days.
Vitamin B12 is another important nutrient for fighting fatigue because it benefits the central nervous system in many important ways: maintaining the health of nerve cells (including neurotransmitters), protecting the covering of nerves called the cell’s myelin sheath, and turning nutrients from food into usable energy for the brain and body.
Probiotic Supplement (50 billion CFU per serving)
Probiotics can help heal the gut and aid in nutrient absorption while reducing inflammation. Other benefits of a high-quality probiotic include helping to maintain a stronger immune system; increasing energy from production of vitamin B12; reducing bacterial or viral growth in the gut such as candida; improving skin health and helping with appetite control and weight loss.
- Hypothyroidism is a condition in which the thyroid gland is underactive and doesn’t properly make or release thyroid hormones.
- There is no cure for a hypothyroidism diagnosis, but there may be ways to naturally increase thyroid hormone production through dietary means.
- When your thyroid is underactive, your metabolism will slow down, which might mean you always feel tired or struggle to keep off weight.
- The hypothyroidism diet eliminates foods that can cause inflammation and immune reactions and instead focuses on foods that help heal the GI tract, balance hormones and reduce inflammation.