Vitamin D and Hypothyroidism

The thyroid gland is butterfly-shaped  gland located at the base of your neck. It is responsible for producing thyroid hormones, T4 and T3, that regulate your metabolism, body temperature, gut motility, brain function, muscle function and more. When the thyroid gland fails to produce adequate amounts of thyroid hormones, something called hypothyroidism can arise and lead to many unpleasant symptoms. 

These include weight gain, fatigue, constipation, dry skin, thinning hair and feeling cold. Hypothyroidism has many causes including non-immune and  autoimmune disease (Hashimoto’s) and affects more women than men. Researchers have found that vitamin D deficiency is extremely common in people with hypothyroidism1, regardless of the cause. In randomized control trials, hypothyriod patients supplemented with vitamin D for 12 weeks improved TSH levels, a marker of thyroid health2 and meta-anaylsis data suggests a beneficial role of vitamin D in managing thyroid disease. 

There are many different reasons why people suffer from hypothyroidism, or an underactive thyroid gland, but regardless of the reason, the unpleasant symptoms remain the same. Weight gain, fatigue, constipation, and dry skin are some of the most common symptoms of hypothyroidism, which most commonly affects women. While hypothyroidism can be caused by a number of different conditions, vitamin D deficiency is extremely common in people with hypothyroidism, regardless of the cause. As a result, scientists have begun studying whether taking vitamin D could be good for people suffering from hypothyroidism. 

What is vitamin D?

Vitamin D has been labeled a fat-soluble vitamin but functions as a steroid hormone that regulates many different actions in the body. Vitamin D plays a role in calcium metabolism and thus bone health but other important functions have surfaced in more recent years through the discovery of vitamin D receptors (targets for vitamin D’s activity) throughout the body from brain health to immune function, glucose metabolism, regulation of inflammation and heart health. 

Vitamin D is found two primary forms: vitamin D2 (from plants) and vitamin D3 (from animals). Food sources of vitamin D2 include mushrooms, olives and fortified foods. Food sources of vitamin D3 include fatty fish like salmon, tuna, mackerel as well as egg yolks, cheese and liver. Vitamin D2 and D3 can also be found in foods that have been fortified with the vitamin by the manufacturers, including certain dairy products, some orange juice, soy milk, and certain cereals. 

Another way to obtain vitamin D3 is through exposure to ultraviolet (UV) rays. The body absorbs the UV rays and through the function of the liver and kidneys, converts it to a usable form. Though this is possible to obtain vitamin D from the sun, each person’s ability to make vitamin D3 varies dramatically due to factors such as skin color (darker skin tones make less vitamin D3), your latitude (the closer to the equator, the better the conversion rates)), sun angle (winter months lead to poor conversion). It is important to have your vitamin D3 levels tested via blood to understand your status and optimize with supplementation. 

The body can naturally produce vitamin D3 when exposed to the ultraviolet rays of the sun for at least 15 minutes per day, but vitamin D2 must be obtained from foods and beverages. Vitamin D is found naturally in relatively few foods, so taking in enough vitamin D is a challenge for many people. As a result, one study found that approximately 40 percent of Americans are deficient in vitamin D. Good natural sources of vitamin D include fatty fish like salmon, tuna, and mackerel, as well as egg yolks, cheese, and beef liver. Vitamin D can also be found in foods that have been fortified with the vitamin by the manufacturers, including certain dairy products, some orange juice, soy milk, and certain cereals. 

Why does the body need vitamin D?

Receptors in every tissue and cell of body. Works as a hormone. 

Works synergistically with other nutrients: mag, calcium, K2, boron, selenium, zinc, copper 

Vitamin D is an essential nutrient that the body needs in adequate quantities in order to function properly. Vitamin D is commonly associated with the development of strong bones and teeth, as it helps the body absorb and use calcium, but it also has many other functions in the body. In addition to enabling the body to absorb and use calcium for bone and teeth formation, vitamin D also performs the following functions: 

  • Supports healthy skin by minimizing and reducing wrinkles and Helps minimize and promoting soft, smooth skin 
  • Improves mental health by helping to reduce the effects of stress and tension 
  • Contains certain properties that may help prevent certain types of cancer and chronic diseases, such as thyroid disorders
  • Prevents the impacts of seasonal depression/seasonal affective disorder (SAD) when produced as a result of sunlight exposure

As researchers continue to dive deeper into the effects of vitamin D on the body, an increasing number of studies have linked vitamin D deficiency to a number of serious health conditions, including thyroid disease, prostate cancer, colon cancer, breast cancer, heart disease, weight gain, and depression. Because vitamin D deficiency is linked to the development of serious health concerns, it stands to reason that correcting the deficiency may be able to effectively treat conditions like thyroid disease,  autoimmune disease, chronic pain, diabetes, high blood pressure, cancer, depression, osteoporosis, and neuromuscular diseases. 

How much vitamin D do you need?

Test blood levels to know what you need 

The amount of vitamin D recommended varies depending on a person’s age. Children less than one year of age should take in 10 mcg, or 400 IU, of vitamin D each day, while children between the ages of one and 18 should take in 15 mcg or 600 IU. Adults between the ages of 19 and 70 should also take in 15 mcg, or 600 IU, while adults over the age of 70 should consume 20 mcg or 800 IU. While these quantities are considered sufficient for 97 percent of healthy individuals, some people may require more vitamin D in order to maintain their health. 

Who is at risk for vitamin D deficiency?

Vitamin D deficiency can happen to anyone, but some groups of people are more at risk of experiencing the condition than others. Vitamin D is not available naturally in many food sources,  so without a diverse, healthy diet, deficiency is extremely common. People who are at an increased risk of experiencing vitamin D deficiency include:

  • People who do not receive enough vitamin D from dietary sources, particularly vegans or other people following a plant-based diet
  • People with limited exposure to sunlight, whether as a result of where they live, clothing worn for religious reasons, or medical conditions 
  • People with darker skin tones, as increased amount of melanin inhibit the body from producing vitamin D in response to sun exposure
  • People with kidney issues, as the kidneys are responsible for converting vitamin D into its active form
  • People with certain digestive issues that impact nutrient absorption, such as Crohn’s disease
  • People who are overweight or obese, particularly those with a BMI of 30 or greater

What is hypothyroidism?

Hypothyroidism is a medical condition characterized by an underactive thyroid gland. People with hypothyroidism have thyroid glands that do not produce enough thyroid hormone in order to keep the body functioning properly. Lack of thyroid hormone causes the processes of the body to start slowing down, which can cause a number of different symptoms. For example, people with hypothyroidism commonly experience symptoms that include:

  • Fatigue
  • Constipation
  • Weight gain
  • Hoarseness
  • Elevated blood cholesterol level
  • Pain, stiffness, or swelling of the joints
  • Thinning hair
  • Depression
  • Enlarged thyroid gland
  • Increased sensitivity to cold
  • Dry skin
  • Puffy face
  • Muscle weakness
  • Muscle aches, tenderness, and stiffness
  • Menstrual periods that are heavier than normal or irregular
  • Slowed heart rate
  • Impaired memory

Hypothyroidism is most commonly experienced by women who are middle-aged or older, but anyone can have hypothyroidism, including infants. Hypothyroidism has many different causes, including:

  • Autoimmune disorders, such as Hashimoto’s thyroiditis or atrophic thyroiditis
  • Surgical removal of part or all of the thyroid gland
  • Radiation treatment
  • Congenital hypothyroidism
  • Thyroiditis
  • Medications such as lithium 
  • Iodine imbalance in the body
  • Damage to the pituitary gland
  • Rare disorders that impact the thyroid

What is the relationship between vitamin D and hypothyroidism?

Doctors and researchers are not entirely sure yet how vitamin D levels impact hypothyroidism, but there does appear to be a link between vitamin D deficiency and hypothyroidism. One study found that 72 percent of people with autoimmune thyroid diseases such as Hashimoto’s thyroiditis suffered from vitamin D deficiency, while 31 percent of healthy subjects were deficient. Another study, conducted in Greece, found that more than 85 percent of people with Hashimoto’s thyroiditis, the most common cause of hypothyroidism, had insufficient levels of vitamin D. However, at the present time, it is not known whether vitamin D deficiency causes hypothyroidism in some people, is a consequence of hypothyroidism, or is unrelated to hypothyroidism and is merely a coincidence. Some researchers postulate that the link between vitamin D and hypothyroidism is based on the fact that healthy levels of vitamin D are essential for proper functioning of the immune system. Therefore, when levels of vitamin D are insufficient, the body may see an increased likelihood of thyroid disease and other types of autoimmune diseases because it cannot properly defend itself. More research is required in order to gain a more complete understanding of how vitamin D levels impact hypothyroidism, but early research does appear to indicate a link between vitamin D deficiency and hypothyroidism.

Is vitamin D good for hypothyroidism?

The same studies that demonstrate a link between vitamin D and hypothyroidism also offer evidence of how vitamin D supplementation can benefit people with the condition. The Greek study mentioned above found that people with Hashimoto’s thyroiditis and vitamin D deficiency showed significantly lower levels of anti-thyroid antibodies when taking between 1,200 and 4,000 IUs per day for four months, representing an increase over the recommended daily allowance of between 600 and 3,600 IUs. A separate study found that taking vitamin D supplements for 12 weeks caused levels of thyroid stimulating hormone, or TSH, in the blood to rise, although it should be noted that this did not correspond to a change in levels of T3 or T4, which are other thyroid hormones. At the present time, no guidelines have been established for the levels of vitamin D supplementation that would be the most beneficial for patients with hypothyroidism. However, it can safely be stated that patients with hypothyroidism should be especially careful to make sure they are taking in adequate levels of vitamin D, either through diet or by taking a whole-foods based vitamin supplement. Because approximately 40 percent of people overall are deficient in vitamin D when relying solely on their diets, a supplement may be the most realistic means by which to ensure proper levels of vitamin D.