Nutrients to Consider for Thyroid Function
Doctor: “Your thyroid results show that you have an underactive thyroid.”
Patient: “Oh ok… so what does this mean?”
Doctor: “We’ll have to start you on thyroid replacement medication.”
Thyroid disease affects millions around the world, and indeed I see many people with thyroid issues in clinic, in particularly an underactive thyroid.
The above interaction is commonplace in conventional medicine, but despite being commenced on synthetic thyroid hormone replacement, many people still continue to experience thyroid related symptoms. Why?
Because the underlying cause for thyroid dysfunction is not being addressed.
In this post we shall take a brief look at some of the essential nutrients for thyroid function through a plant based diet (a diet that constitutes whole and natural plant foods, namely: fruits, vegetables, whole grains, legumes, nuts and seeds)
What is the thyroid gland? The thyroid gland is a butterfly shaped organ that sits in your neck.
What does it do? The thyroid gland plays a major role in metabolism, growth and development of the body. It does this through the production and subsequent action of thyroid hormone.
Thyroid hormone is made up from iodine and tyrosine, either as T3 (active) or T4 (inactive).
IODINE
Iodine is only needed in small amounts (daily intake around 140-150 micrograms a day), but is essential to the production of thyroid hormone. The body converts it into the iodide ion, which is then used to make it.
Sources of iodine include sea veg such as nori and dulse (see this short video for more info https://www.youtube.com/watch?v=JOFvSaXE02c).
Other sources can include fruits, land veg, mushrooms and sunflower seeds.
TYROSINE
Tyrosine is an amino acid, and amino acids are the building blocks of protein. Tyrosine can actually be made by the body from another amino acid called phenylalanine, and so is not considered essential (unlike phenylalanine which is considered essential, meaning it can only be obtained through the diet).
Plant based sources of tyrosine include: peanuts, almonds, pumpkin seeds, sesame seeds, soy products, lima beans, avocados, bananas.
Sources of phenylalanine include: tofu, beans, nuts, seeds, pasta, whole grains, and vegetables like sweet potatoes.
IRON
There is an enzyme called thyroid peroxidase (TPO) which aids in the production of the T3 and T4 hormones. This enzyme requires iron in order to be able to function.
Sources of iron include: Legumes, whole grains, vegetables (such as spinach), pumpkin seeds and dried fruit. Dark chocolate and black strap molasses can be good sources too. Interestingly, acidic foods such as tomato sauce, when prepared in iron cookware, can take up some of the iron from it.
SELENIUM
This trace element has an important role to play in thyroid function.
In order to protect the thyroid from damage (oxidative stress) through its metabolic activities, selenium plays an important role in the production of an antioxidant called glutathione peroxidase.
Remember earlier we mentioned that the thyroid gland produces the active T3 thyroid hormone and the inactive T4? This means that T3 is what the body uses, and T4 is the standby version. This is done ‘intentionally’ so that not too much T3 is made in one go, as otherwise it could over-activate the body. So T4 acts as a more stable version, which can be converted to T3 in other parts of the body as required. And selenium is needed to produce the deiodinase enzymes necessary for this conversion.
Selenium also helps TPO in its role.
Sources of selenium include: Brazil nuts, brown rice, buckwheat, whole wheat spaghetti and other wholegrains, beans, nuts and seeds.
ZINC
This mineral seems to have a number of roles in thyroid function. These include the regulation of the deiodinase enzymes as mentioned above, and also of Thyrotropin Releasing Hormone (TRH) and Thyroid Stimulating Hormone (TSH) made by the hypothalamus and pituitary gland respectively, which stimulate the production of thyroid hormone.
Sources of zinc include: seeds, nuts, legumes, tofu, whole grains and brown rice. To improve zinc absorption, fermenting, leavening (bread), soaking (whole grains, legumes, nuts, seeds), sprouting are good methods to use.
Adding garlic to e.g. hummus or rice can increase zinc uptake.
COPPER
Copper has a role to play in the conversion of T4 to T3 too.
Sources of copper include: legumes, whole grains, nuts, seeds, kale, spinach, avocado, dried fruits, peas, potatoes, mushrooms
VITAMIN D
Vitamin D has been shown to play a role in immune system function, with lower levels being associated with autoimmune disease (where our own immune system attacks the body) e.g. Hashimoto’s hypothyroidism. Vitamin D has been shown in studies to play a role in thyroid functioning, and so it would be prudent to have your vitamin D levels checked as part of thyroid function.
The reliable way to get enough vitamin D is through supplementation, especially in the UK. But it’s always important to make sure you get your level checked first to see whether you are deficient or already near the top for example (there is a risk of overdosing with vitamin D, but it is safe to take daily doses of around 1000iu daily without worrying about overdosing), aiming for a level of around 75-100nmol/L. I supplement 3-4 times a week with Cytoplan wholefood vitamin D3 2500iu vegan capsules.
Sources of Vitamin D include: fortified foods such as plant milks and cereals (but be aware that cereals can be processed and contain lots of other ingredients e.g. sugar)
VITAMINS C & E
These two vitamins are antioxidants and so can help with oxidative stress.
Vitamin C also helps TPO with its function.
Sources include: a variety of fruits and vegetables. Additionally, vitamin E can be found in avocado, nuts, seeds and wholegrain
VITAMIN A
Vitamin A has been shown to regulate TSH and thyroid hormone production.
It helps TPO carry out it’ job.
Sources of vitamin A come in the precursor form (carotenoids) and include: deep-orange fruits and veg such as carrots, peppers, sweet potatoes, tomatoes, squash; and green leafy vegetables, broccoli, turnips.
Cooking allows the better absorption of some carotenoids such as lycopene from tomatoes.
Vitamins A,D & E (as well as vitamin K) are fat soluble vitamins, so it may be worth consuming these food sources with a plant based fat source such as nuts, seeds, avocados, olives.
B VITAMINS
Vitamin B2, B3 & B6 play a role in thyroid hormone production. Along with other B vitamins they play an important role in cellular reactions and energy production.
Vitamins B2, B3 and B6 help with TPO functioning.
Sources of these B vitamins include a whole variety of whole foods.
So as you can see, there are a number of different nutrients that play a really important role in thyroid function.
Many people worry about goitrogens – substances said to interfere with iodine uptake into the thyroid gland, found in cruciferous veg (such as broccoli), cassava, soy beans, peanuts, millet. However this may only pose an issue if one is iodine deficient. Besides, they would have to be eaten in quite high amounts, and goitrogens are inactivated by cooking the food. Here are two short videos for further information on this: https://www.youtube.com/watch?v=OdEzzuWW3Ao; https://www.youtube.com/watch?v=Snr9OUUut6c.
Now I’m not saying the thyroid medications we prescribe in conventional medicine are never necessary, and I’m certainly not telling you to stop your medications if you’re currently on them. But at the same time it is really important to start at the foundations and address root causes of issues, with a whole food plant based diet being a massive part of the solution. It is through a holistic approach that we can prevent, improve and reverse disease processes.
Further links and resources:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3847753/
https://www.ncbi.nlm.nih.gov/pubmed/22009156
https://www.ncbi.nlm.nih.gov/pubmed/30982439
https://www.ncbi.nlm.nih.gov/pubmed/30208979
https://www.ncbi.nlm.nih.gov/pubmed/12487769
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6166548/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5618598/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3921055/
https://www.ncbi.nlm.nih.gov/pubmed/23378454
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2266752/
https://www.ncbi.nlm.nih.gov/pubmed/18655403
I hope this information has been useful. If you’re struggling with your thyroid health and would like a more natural approach, then please contact The Green Doctor.
