Vitamin A Deficiency and Thyroid Balance written for Thyroid UK
Thursday 25th June 2020
For the full magazine click on www.thyroiduk.org
The Effects of vitamin A Deficiency on Thyroid Health
By Melissa Cohen, Nutritional Therapist BSc (Hons), mBANT, mIFM, NLP Practitioner
When you think of key nutrients for the thyroid; iodine, selenium and vitamin D spring to mind and quite rightly so.
Of course, those nutrients are important for production of thyroid hormones; thyroxine (T4) and triiodothyronine (T3) and for the conversion of T4 to the more metabolically active T3.
Vitamin A is required to activate thyroid hormone receptors to enable thyroid hormones to get into the cells. Thyroid Receptors sit on the outside of the cell and bind to thyroid hormones known as thryoxine. Insufficient vitamin A may prevent thyroid hormones entering the cell and consequently send signals to the pituitary gland to increase Thyroid Stimulating Hormone (TSH) that can lead to an enlarged goiter and a diagnosis of Hypothyroidism.
A study in Africa outlined that children are at risk from both iodine and vitamin A deficiency. This study measured the effects of supplementing both those nutrients over 10 months. The conclusion was vitamin A deficiency along with iodine is correlated to elevated TSH and elevated total T4 levels (Free T4 levels are more important as they are activated in the cell). During the intervention of supplementing with vitamin A, TSH decreased along with the goiter.
Conversely a study found high dose vitamin A supplementation decreasing symptoms and markers of Hyperthyroidism. The researchers for this study hypothesized that high dose vitamin A may suppress TSH.
Therefore based on all the research it could be argued that Hypothyroidism with a vitamin A deficiency and Hyperthyroidism could benefit from supplementation.
In my experience, some form of ongoing stress usually triggers thyroid imbalances, whether it is a stressful job, personal upset or long-term anxiety. This can impact absorption of nutrients and in turn disrupt the thyroid due to nutrient deficiencies and elevated stress hormones. If this elevation of stress hormones and depletion of nutrients continues then the thyroid will eventually be imbalanced.
I would suggest vitamin A is an important nutrient for the thyroid, mainly as it impacts the thyroid receptors, which helps the thyroid access our cells from the blood stream and that's when they become active.
It is fairly easy to consume vitamin A due to being in so many foods. The most potent form of vitamin A is from animal rich foods, known as Retinol. The less potent form is from plants called Carotenes - which is why you might have heard of the old saying of "eating carrots help you see in the dark ".
Sources of Vitamin A
1) Retinol include
• Egg yolk
• Oily fish
Retinol has a high absorption rate between 70-90% which means on average 80% of vitamin A found in animal foods is absorbed by the body.
2) Carotenes include
• Butternut squash,
• Sweet Potato
• Cantaloupe Melon
• Orange Pepper
Carotene has a lower absorption than Retinol, between 5-60% on average that means 33% of carotene found in plants is absorbed by the body.
Classic signs of low vitamin A
• Hyperkeratosis on skin (raised pimples on skin)
• Lowered immunity
• Eczema/dry skin
• Night Blindness
There are a number of reasons vitamin A levels could be low:
• Not eating enough vitamin A rich foods
• Insufficient bile and Lipase to break down fat and absorb the vitamins
• Compromised BCMO1 gene which converts carotene to Vitamin a / Retinol
• Gall bladder removal
• Leaky gut also known as dysbiosis
• Coeliac Disease
• Diabetes Type I and II
• Crohn's Disease
• Chronic Irritable Bowel Syndrome
• Hypothyroidism (as thyroid function is required to convert carotenes to vitamin A / retinol)
Delicious vitamin A rich recipes for all the family
Fresh Tomato Soup
12 tomatoes on the vine big tomatoes not cherry tomatoes
1 red onion
1 white onion
2 tbsp. olive oil or more
1 garlic crushed
Large handful of fresh Basil
1.5 litres of water mixed with chicken stock
Sea salt and black pepper
Heat olive oil in pan and sauté onions, then garlic. Meanwhile wash and cut tomatoes into quarters and place in pan, with water and stock. Add Basil leaves and bring to the boil and simmer for 60 minutes. Season with salt and and pepper. Leave in pan to cool for 30 minutes, to create a rich tomato flavour.
Use sieves and pour soup through sieve to catch the skin, pith and tomato seeds. To create a smooth tomato soup.
TIP: You may add big dollop of Greek Yoghurt when serving or a tbsp. of seeds to add protein to your soup.
Carrot and Orange and nut Salad
8 small nuts
2 carrots - grated
1 orange or 2 tangerines segmented
Bunch of fresh coriander
Place all ingredients together in a large bowl and serve with a plain yoghurt dressing (plain yoghurt dressing - 3 tbsps. plain yogurt , 1 tablespoon lemon juice, 1 tsp. Maple Syrup
Roast Sweet Potato and Aubergine Salad
2 large sweet potato cut into small chunks
1 large cauliflower, cut into florets
4 tbsp. olive oil
pinch of paprika
pinch of sea salt
pinch of black pepper
3 tbsp. Tahini
4 tbsp. water
1 tbsp. lemon juice
2 garlic cloves, crushed
handful of coriander
• Preheat oven to 200 deg. C
• Line 2 baking trays with baking paper, lay cauliflower florets on one tray and sweet potatoes on the other
• Drizzle olive oil over potatoes and season with salt and pepper and paprika
• Place both trays in oven and cook for 45 mins. Keep turning cauliflower over to prevent from burning (every 10 mins)
• For Tahini dressing - mix all ingredients
• When cooked drizzle tahini dressing over salad and garnish
If you are concerned you may have a vitamin A deficiency it is important to get tested as vitamin A is a fat-soluble vitamin that is stored in the liver. Too much vitamin A creates toxicity.
You can contact me at firstname.lastname@example.org to arrange a nutritional consultation and to discuss vitamin A testing. Additionally, if you would like to hear more about how I work drop me an email to arrange a complimentary 10-minute chat.