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Q: Thyroid and Vitamin C ( Answered,   5 Comments )
Subject: Thyroid and Vitamin C
Category: Health
Asked by: jat-ga
List Price: $20.00
Posted: 11 Jun 2004 15:50 PDT
Expires: 11 Jul 2004 15:50 PDT
Question ID: 359889
I'd like to know all the in's and out's having to do with a possible
connection between the Thyroid and Vitamin C.  How and in what way
does Thyroid effect Vitamin C?  Or, perhaps it's better asked the
other way around: How does Vitamin C effect the Thyroid?  In what ways
complementary?  Antagonistic?
Subject: Re: Thyroid and Vitamin C
Answered By: crabcakes-ga on 12 Jun 2004 19:24 PDT
Hi jat,

When we read about Vitamin C deficiency, the word "thryoid? is almost
never seen. Likewise, when we read about the thyroid gland, Vitamin C
is almost never mentioned. There is a connection, albeit not a
prevalent one. Very few people in developed countries suffer from
Vitamin C deficiency, particularly since Vitamin C, also known as
ascorbic acid, is a common food preservative, making ?C? deficiency
quite rare.

The thyroid gland produces hormones that regulate protein,
carbohydrate, fat, and vitamin metabolism, along with generation of
body heat. Thyroid hormones also regulate the activity of the
autonomic nervous system. Hormone levels secreted by the thyroid are
controlled by the pituitary gland's thyroid-stimulating hormone(TSH),
which in turn is controlled by the hypothalamus.

The primary hormones produced by the thyroid gland are T3 and T4. T3
needs 3 atoms of iodine, and T4 needs 4 atoms of iodine to be
effective. Why are we talking about iodine? In order for iodine to be
utilized properly, it requires the presence of tyrosine, an amino acid
and precursor of thyroid hormones, as well as being necessary for
adrenaline and noradrenaline production. Vitamin C is necessary for
tyrosine metabolism, and it is quite a delicate balance!

?Stress is known to affect thyroid function. The amino acid tyrosine
is necessary for the production of steroid hormones adrenaline and
noradrenalin. When the body is under stress more of these hormones are
required and tyrosine reserves are depleted, leaving the thyroid
hormone pathway under functioning. Stress depletes many of the
essential nutrients required for thyroid function ? the B vitamins,
vitamin C, zinc and selenium especially.
Individuals who are stressed may therefore require additional adrenal
support in order to improve their thyroid function. There are many
nutrients and herbs, which can help support the adrenal glands.?

?The thyroid hormones travel through the bloodstream to every cell in
the body, where they keep everything working optimally, like oil in an
engine. Without enough thyroid hormone in its active state (T3), the
metabolism slows down, resulting in lowered pulse rate, coldness,
weight gain, and fatigue. Other body functions slow down as well?the
mind can't function normally, skin becomes dry and flaky, hair falls
out, muscles become cramped, and so on.?

?Vitamin C promotes healthy teeth and gums, helps in the absorption of
iron, aids in the maintenance of normal connective tissue, and
promotes wound healing. It also helps the body's immune system.?

Vitamin C does play a role in thyroid hormone production, according to
the University of Maryland Medical Center:
·Avoid foods that suppress thyroid function, including broccoli,
cabbage, brussels sprouts, cauliflower, kale, spinach, turnips,
soybeans, peanuts, linseed, pine nuts, millet, cassava, and mustard
·Avoid refined foods, dairy products, wheat, caffeine, and alcohol. 
·Essential fatty acids (1,000 to 1,500 mg three times per day) are
necessary for hormone production.
·Vitamin C (1,000 mg three to four times per day), vitamin A (10,000
to 25,000 IU per day), B complex [(50 to 100 mg/day), augmented with
vitamins B2 (riboflavin, 15 mg), B3 (niacin, 25 to 50 mg), and B6
(pyridoxine, 25 to 50 mg)], selenium (200 mcg per day), iodine (300
mcg per day), vitamin E (400 IU per day), and zinc (30 mg per day) are
necessary for thyroid hormone production.
·L-tyrosine (500 mg two or three times a day) also supports normal
thyroid function. May make high blood pressure worse.
·Calcium (1,000 mg per day) and magnesium (200 to 600 mg per day) help
many metabolic processes function normally.

However, once Vitamin C reaches a certain level, our kidneys excrete
amounts over that threshold. This means don't overdo the "C"! 
?Ascorbic acid in excess of bodily requirements is excreted, largely
unchanged, in the urine. There is a renal threshold of about 14
mcg/mL, and increasing amounts of ingested ascorbic acid are excreted
unchanged in the urine when the daily intake exceeds 200 mg.

What's wrong with taking high doses of vitamin C? 
?Some people believe that because vitamin C is water-soluble, it is
safe to take in high doses. While it is best to not exceed the
recommended upper intake level of 2,000 mg a day, the most serious
possible consequence of an intake above this dosage is diarrhea.
One myth about vitamin C is that it is an antioxidant, but that is not
completely true. Vitamin C is a redox agent, meaning that it acts as
an antioxidant in some cases, and an oxidant in others. Antioxidants
are important because they inhibit chemical reactions with oxygen or
highly reactive free radicals. These reactions (oxidation reactions),
cause damage to cells. Vitamin C only acts as an antioxidant in some
Vitamin C is an important part of a healthy diet. It is not a miracle
drug, and may cause harm if taken in extreme excess. A well-balanced,
varied diet will ensure that you receive more than enough vitamin C to
prevent scurvy and other potential health problems.?

Diseases such as  goiter and Graves?  cause a thyrotoxicosis
(hyperthyroidism), which requires a larger than normal amount of
Vitamin C to maintain production of T3 and T4. ?Most patients with
Graves? disease have T3 thyrotoxicosis while they are hyperthyroid.
That is, levels of T3 in their blood are proportionately higher to T4
than the ratio seen in normal people. This excess T3 contributes to
many of our symptoms. Our cells also begin to depend on it more for
proper function. Suddenly deprived of T3 when we become hypothyroid
and begin T4 treatment, symptoms of T3 deficiency emerge. For many of
us, those symptoms never abate until we?re treated with either a
combination of synthetic T4 and T3 or glandular extract?

?Thyrotoxicosis increases vitamin C requirements?

?Many nutrients are important for maintaining the health of the
thyroid gland. Vitamin C, vitamin E and the B complex vitamins may
help in the treatment of hyperthyroidism and hypothyroidism because
they play key roles in improving the overall healthy function of the
thyroid gland and the immune system. If you have a sluggish thyroid
you may need to take prescribed supplements under a doctor's
Readers Digest, British Edition

?Vitamin C plays a key role in boosting immune system?and thyroid
gland?function. It's important in the treatment of both
hyperthyroidism and hypothyroidism.?,1459,520,00.html

Additional Reading:
You can see an illustration here on the connection between the
thyroid, hypothalamus and pituitary glands.

Thyroid Hormones

The Thyroid Gland

An interesting story on Hamburger Thyrotoxicosis

I hope this answers your question. If any part of my answer is
unclear, or if I have duplicated information you already had, please
request an Answer Clarification, before rating. This will allow me to
assist you further, if possible.

Search Terms
Role ascorbic acid thyroid function
Role ascorbic acid T3 T4 
T3 T4 synthesis
Vitamin C production thyroid hormones
Subject: Re: Thyroid and Vitamin C
From: chandr-ga on 12 Jun 2004 10:50 PDT
Why do U want to know?
It just seems pointless.

I know of a link of ascorbic acid with adrenal, though.
Subject: Re: Thyroid and Vitamin C
From: gmanepal-ga on 12 Jun 2004 13:33 PDT
Some useful information about Hypothyrodism that links to Vitamin C is
available in the following link:
vitamin C 
Vitamin C plays a key role in boosting immune system?and thyroid
gland?function. It's important in the treatment of both
hyperthyroidism and hypothyroidism.
Leading Food Sources of vitamin C: Cabbage, red, Potatoes,
Strawberries, Tangerines & other mandarins, Peppers, bell, red,
Oranges, Kiwi fruit
Subject: Re: Thyroid and Vitamin C
From: jat-ga on 12 Jun 2004 17:37 PDT
To: "chandr-ga"

First off, I'll take any ascorbic acid/adrenal links you can send me. 
Secondly, though, you say my question is pointless.  Aside from the
fact it surprised me a researcher would opine in this way, you've got
me curious: why do you say this?...
Subject: Re: Thyroid and Vitamin C
From: pinkfreud-ga on 12 Jun 2004 17:42 PDT

Please note that chandr-ga is NOT a Google Answers Researcher. All
authorized Researchers' usernames are highlighted and "clickable."
Anyone can become a site user and post a Comment, but only official
Google Answers Researchers may post Answers. Your account is not
charged for Comments.

~pinkfreud-ga, Google Answers Researcher
Subject: Re: Thyroid and Vitamin C
From: gfv-ga on 13 Jun 2004 00:56 PDT
Thank you! I found what you said very helpful. I was diagnosed with
Graves and after a year on Tapozole pronouced "cured." However, I
cannot get my body temperature regulated. If it is over 65 degrees I
am sweating profusely. It is amazing how much the disease affects ones
body and quality of life. I have many other symptoms, but don't seem
to find any support groups, etc. for Graves. In less than 3 months I
lost and put on 60 pounds. It just never seems to end.

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