The Best Vitamins for Thyroid Disease

Various supplements and vitamins can be taken when it comes to thyroid disease. This is certainly not a one-size fits all picture. While the web can be a source of an immense amount of information, with that comes a lot of misinformation. When we consider vitamins for thyroid disease, the first question we must ask is:

• Is this for a sluggish thyroid or hypothyroidism?
• Is this for hyperthyroidism?
• Is this for autoimmune thyroid disease?
• What is my nutrient status?

In general, there are certain vitamins that can be useful in supporting thyroid health, regardless of the type of thyroid disease, but there are others that you should perhaps avoid or supplement with, specifically. 

Let’s start with how your thyroid functions. Your anterior pituitary releases a peptide hormone called Thyroid Stimulating Hormone, also known as TSH for short. This controls how much thyroid hormone your thyroid produces. Thyroid stimulating hormone binds to a receptor on the cells on your thyroid, causing them to produce thyroid hormone. Here’s where it gets interesting… 

Your thyroid hormones have what is known as a negative feedback reaction on your pituitary gland. This happens when you have too much thyroid hormone. When you have too much thyroid hormone, it sends a signal to your pituitary gland to stop the production of thyroid-stimulating hormone.

This is why hyperthyroidism is often explained by a LOW thyroid stimulating hormone (TSH) value and hypothyroidism is diagnosed with a HIGH thyroid stimulating hormone (TSH). 

Where do vitamins come in?

Our two main thyroid hormones, T4 (thyroxine) and T3 (liothyronine), rely on several factors, including vitamins. Liothyronine is considered to be your most active thyroid hormone. 

When we check for these values in your blood, we look for the free form of T4 and T3 as that is what is most freely available. We also look at reverse T3, as when that value is elevated, it signifies you may not have enough of your active free T3 hormone available. 

In order for you to be able to properly convert from free T4 to your most active thyroid hormone, free T3, you need certain vitamins and nutrients. We should preface this with saying that sometimes less is more, and too much of certain nutrients can cause more harm than good. 

Below is a graphic that shows the factors that may contribute to increased or decreased thyroid function:

Many of these nutrients, like iron, iodine, tyrosine, zinc, and selenium, are necessary to facilitate the conversion of free T4 to T3. If you are deficient in any of these nutrients, you can experience suboptimal conversion to T3 and experience hypothyroid symptoms like:

• Weight gain
• Constipation
• Dry skin
• Slow metabolism
• Hair loss
• Fatigue
• Muscle cramping
• Sensitivity to cold

Iron

Let’s start with iron and why it is so important. Hypothyroidism affects more females than males. Similarly, women are at higher risk for developing iron deficiency anemia because menstruating women, in particular, lose iron during their period and have an increased need for iron during pregnancy and lactation.

This is why it is so important to get routine blood work. Treating the root cause of your disease can be extremely beneficial when it comes to long-term therapy. When checking for iron deficiency, make sure your Doctor not only checks your complete blood count (CBC), but also looks at your iron, TIBC (total iron binding capacity), % iron saturation, and ferritin.

Ferritin is a protein that stores iron in your cells, so low ferritin often indicates low iron. When ferritin is tested in the blood, the “normal” reference ranges are usually between 15-150. This range is far too wide to indicate optimal iron levels. An optimal ferritin range is around 70.

Clinically, we often see that women with hypothyroidism who have iron deficiency begin to feel significantly better and are often even able to lower their dose of thyroid medicine when properly supplementing with iron. We advise speaking with your Physician about testing and properly treating iron deficiency. Depending on how deficient our patients are in iron, we replete iron through iron-rich foods, supplements, and even iron IVs in some patients.

Iodine

You mentioned iodine.. how much iodine should I be having per day? The recommended daily allowance for iodine intake is 150 mcg in adults and slightly more in pregnant and breastfeeding women. While this nutrient is important for proper thyroid function, research shows that too much iodine intake may contribute to hypothyroidism.

This is one of those nutrients that can cause more harm than good if taken in excess. For this reason, we often recommend avoiding supplementing with any iodine, especially until your physician assesses your urinary iodine. If you are curious whether you are getting too much or too little iodine, ask your physician to run a urinary iodine/creatinine ratio. Iodine deficiency has become rare, though, given that many salts and foods are fortified with iodine, so we typically recommend avoiding excess iodine until you speak to your Physician. 

Where can I be getting excess iodine from?

Fish, seafood, and seaweed contain high levels of iodine. Other dietary sources of iodine include eggs, dairy products, and iodized salt. Other sources of iodine could be found in your daily multivitamins and may even be found in some of your favorite skincare products.

Zinc and selenium

Both zinc and selenium are essential trace elements that are involved in thyroid metabolism. Ask your physician to check for your zinc and selenium levels in your blood. It should be noted that the best way to test for these two elements is the amount available in the red blood cell. Ask your physician to run: Zinc (RBC) and Selenium (RBC) for the most accurate results.

If your levels are not optimal, your doctor may recommend supplementing with zinc and or selenium. You can get both from your diet as well. Interestingly enough, brazil nuts are very rich in selenium, and just 2-3 brazil nuts per day can provide you with enough selenium for the whole day! If you supplement with zinc, be sure to do so with food to avoid any gastrointestinal upset! 

What is tyrosine?

Tyrosine is a non-essential amino acid that acts as a building block for your thyroid hormones. Oftentimes, many thyroid-supportive supplements contain tyrosine. You should always consult with your doctor before starting any new supplements, but make sure you avoid tyrosine supplementation if you have HYPERthyroidism. 

Other vitamins that help with thyroid function include B vitamins and vitamin C. You can test for each individual vitamin or speak to your doctor about proper supplementation!

It’s important that you’re aware of the nutrients necessary for proper thyroid function so you and your Doctor can properly treat your thyroid condition and perhaps even prevent thyroid disease in some by treating the root cause.