Your thyroid is located in the neck and iodine is required for efficient thyroid function.
Hypothyroid (Under Active)
Updated Jun. 24th, 2026 | Read Time: 7 Minutes | What You Will Learn:
- Diagnosing Hypothyroidism
- Symptoms of Hypothyroidism
- Key Hypothyroid Supporting Supplements
- Iodine As A Thyroid Supplement
- Treatment Options & Supplements For Hypothyroid Support
- Conventional Treatments For Hypothyroid
- Nutritional Supplements For Hypothyroid
- Lifestyle Factors For Hypothyroid Support
- Nutritional Information
- Reader Comments (6)
Low thyroid has become a very common health concern with very real symptoms that affect both a person’s physical and emotional health. Many people may have it yet do not know; in fact, it can go undiagnosed for many years because the “normal” level of thyroid hormones can vary from person to person. Let's explore ways to diagnose hypothyroidism, as well as supplements that can help with hypothyroid symptoms.
Diagnosing Hypothyroidism
Many natural health care practitioners prefer the reliability of the basal temperature test (done in the morning) because it can identify people with borderline low thyroid. There can be many causes of low thyroid, including: hormonal changes (especially during pregnancy), lack of iodine in the diet, an abnormal immune system reaction (as in Hashimoto’s), heredity, stress, treatment for an overactive thyroid, chemical pollutants and heavy metal poisoning. It is important to discover the exact cause of low thyroid so that the root cause can be treated.
Low thyroid causes the body to be slightly colder than that of a healthy person. While only the difference is at most two degrees, it can have broad ranging effects on many different functions of the body, resulting in many different symptoms.
Symptoms of Hypothyroidism
Firstly, in a hypothyroid state, the body’s metabolic rate is decreased. This is why most people with low thyroid experience weight gain. Secondly, lower thyroid hormone levels can disrupt neurotransmitter production and function. These changes may cause depression, anxiety, poor memory, and insomnia. Reduced body temperature can impair digestive enzyme activity. This dysfunction may cause gas, heartburn, constipation, and stomach upset. Low temperatures can also affect insulin function. Many people with hypothyroidism experience blood sugar fluctiontions. Some symptoms may require additional treatment alongside thyroid support.
Low thyroid can also: lower immune system function, cause dry skin, lower blood pressure and raise cholesterol, promote water retention, cause menstrual irregularities in women, cause muscle aches and pain, and create allergies. Hypothyroid sufferers also report fatigue, an increased need for sleep, decreased initiative, lack of concentration, poor memory, bowel changes, muscle and joint aches, and asthma. Because of the broad range of effects that low thyroid has on overall health, it is important that it be treated. Left untreated, long-term hypothyroidism can cause serious concerns that can affect your quality of life.
Key Hypothyroid Supporting Supplements
Iodine As A Thyroid Supplement
Iodine is a mineral needed for all aspects of your health. Potassium iodide is a salt of stable iodine. For the most part, we can get adequate amounts of stable iodine from the foods that we eat. Potassium iodide is a medicinal form of stable iodine.
Radioactive iodine enters the air after nuclear or radiological events. People can inhale it or consume contaminated food and water. Once present in the body, the thyroid gland will begin to rapidly absorb it/take it up. Potassium iodide competes with radioactive iodine at receptor sites. It fills these sites and prevents the thyroid from taking up any of the radioactive substance. Its action at these receptor sites lasts 24 hours, meaning the thyroid is unable to take up any iodine – stable or radioactive – during that time.
Often difficult to get from the diet, iodine is an essential trace mineral necessary for overall health. Your thyroid gland needs this mineral to manufacture optimum levels of the thyroid hormones thyroxine (T4) and triiodothryonine (T3). These hormones – based on iodine and the amino acid tyrosine – regulate your body's overall metabolism and also play a regulating role for other hormones produced by the body.
When there is not enough iodine present, your thyroid (located in the throat area) is unable to produce enough thyroid hormone, causing weight gain, low energy, poor concentration (brain fog), depression, blood sugar fluctuations and other symptoms.
It is important to understand that potassium iodide does not protect the body as a whole from radioactive iodine, nor does it prevent any other body part from taking it up. Its actions are very specific to the thyroid. It has no effect on other radioactive elements, like cesium, nor on the effects these elements may have on the body.
Infants and children are at the highest risk of developing thyroid cancer due to an accumulation of radioactive iodine. Infants who are breast feeding still need some sort of supplementation, as the breast milk will not contain enough stable iodine to protect the infant from exposure. Adults aged 18 and older should take 130mg of potassium iodide. Children ages 3 to 18 should take 65mg. Adult-sized adolescents should take 130mg. Children ages one month to three years need 32mg. Newborns require 16mg.
Dosing Iodine
A one time dose of potassium iodide is usually all that is recommended . If there is a threat that radioactive iodine will be in the environment for longer than 24 hours, public health officials may inform the public to take the supplement for a few days in a row. Please seek the advice of your local healthcare practitioner or public health agency. High doses or long-term potassium iodide use can pose health risks. Infants, children, and people with thyroid disorders face greater risks. Taking extra potassium iodide provides no added protection. Excessive use may increase the risk of side effects.
Consuming Iodine
Dietary iodine has become difficult to obtain naturally. Manufacturers now fortify staple foods such as salt with iodine. Iodized salt contains an inorganic form of iodine. Natural, organic sources, such as those derived from the seaweeds kelp and bladderwrack, are much more absorbable and easier for the thyroid gland to use than the inorganic (mined) sources used to enrich foods.
Iodine Supplements For Hypothyroid Support
Supplement manufacturers often source iodine from seaweed. They offer iodine in liquid, capsule, and tablet forms. The standardized types of these supplements contain a higher level of iodine and a consistent amount in each tablet – usually about 150mcg. This is the preferred form for clinical use in low thyroid conditions, while the un-standardized kelp is suitable for people in need of a daily supplement.
Treatment Options & Supplements For Hypothyroid Support
Conventional Treatments For Hypothyroid
Conventional treatment of hypothyroidism involves supplementation with synthetic thyroid hormone.
Most hypothyroid patients benefit from T4 supplementation but it must be converted by the body into active T3. In a small percentage of people, this conversion is inadequate. They require medication that contains both T3 and T4.
Side effects of these medications cause similar symptoms to hyperthyroidism. They can also cause a loss of bone mass. Many medications can interact with thyroid medication.
Talk to a health professional to determine the best time to take your medication. Avoid taking thyroid medication with calcium supplements.
Nutritional Supplements For Hypothyroid
Nutritional support for an underactive thyroid gland can include, among many other supplements, thyroid glandular extract. Thyroid glandular boosts the activity of your own thyroid gland, optimizing its production of T3 and T4. Ensuring that you are getting enough of important nutrients like iodine and tyrosine is crucial for natural thyroid support. Please see the table below for extensive information about which supplements can be used as part of a thyroid support regimen.
Lifestyle Factors For Hypothyroid Support
Exercise is important when you have low thyroid. Daily aerobic exercise stimulates the thyroid gland and improves the use of thyroid hormone in the body. Saunas, steam baths and dry skin brushing stimulate the thyroid. Regular detoxification programs are important because low thyroid can cause you to retain more toxins than a healthy person. Toxicity may also play a role in the development of the disorder itself.
Dietary treatment of hypothyroidism involves ensuring adequate iodine, copper, zinc, selenium, vitamin A and vitamin E intake. Consume the following foods: seaweeds, fish, clams, lobster, oysters, eggs, natural yogurt, unhomogenized milk, raw wheat germ, pumpkin seeds, beet greens, parsley and carrots. Avoid chlorinated and fluoridated water because they block iodine receptors in the thyroid. Avoid broccoli, brussels sprouts, cabbage, cauliflower, kale, peaches, pears, rutabagas, soybeans, onions, spinach and turnips because they suppress thyroid hormone function.
Overall, once you know you have low thyroid, half the battle is over. You might notice that when you are under stress, your symptoms of low thyroid are more pronounced. It is important - as with any major health concern – that you maintain a positive attitude and remain focused on your treatment protocol. Dealing with low thyroid can be frustrating, but not as frustrating as letting the symptoms go untreated.




Very informative article as it explains everything that you generally need to know about having low thyroid. It took me a number of years to get properly diagnosed as I have the subclinical version of hypothyroidism. But, since I've been taking the natural dessicated thyroid with active hormone in it, I've been feeling like my normal self again. Be sure to keep an eye on your blood sugar too, as people who have poorly functioning thyroids often have to deal with that also.
Hello Jennifer,
We're glad you found our article informative, it's nice when you can get so much information in one place. We're glad you've gotten a hold on your health concern.
Stay healthy & well.
This is an excellent read. I had surgery years ago and 3/4 of my thyroid was removed, now that little bit that is left has started to go wonky. The vitamins and minerals to take are a great help.
Hello, Sheila,
We're happy this article is able to help you take care of your thyroid, especially given your unique experience. Thank you for sharing and we hope these supplements help your thyroid thrive.
Since you're enjoying these articles, we think you'll enjoy our YouTube channel with informative videos as well:
https://www.youtube.com/@NTLnutrition/featured
Stay healthy & well.
The thyroid is so very important to health as the metabolic master gland. I appreciate how you clearly describe symptoms which might indicate that one might have low thyroid, what one might expect to experience with low thyroid as well as measures to promote health. As always, I appreciate your list of supplements that might be helpful for the condition. The thyroid is so very important and I am so very lucky that mine is functioning well!!
Hello Rachel,
Indeed it is. Thank you for sharing your key takeaways form this article. Don't forget to check out our other article on thyroid health: https://www.nationalnutrition.ca/articles/health-concerns/hyperthyroid/