Drinking Lots Of Green Tea A Risk For Low Thyroid?

[DMF]

Is drinking 3-4 cups of green tea a day have a possible negative effect on Thyroid Levels ?
I believe my "male hot flashes" began around the same time I started drinking green tea.

 

[Nicole W.]

Is drinking 3-4 cups of green tea a day have a possible negative effect on Thyroid Levels ?
I believe my "male hot flashes" began around the same time I started drinking green tea.

In my experience, yes. I was drinking copious amounts of green tea when I was first diagnosed with low thyroid. I don’t think the green tea was the only contributing factor, but I don’t think it helped. I rarely drink green tea now and when I do it doesn’t make me feel well.

 

[Tristan Loscha]

Is drinking 3-4 cups of green tea a day have a possible negative effect on Thyroid Levels ?
I believe my "male hot flashes" began around the same time I started drinking green tea.

It could be anything, i would stay away from Tea and drink Coffee only.



. 2001 Dec;75(10):591-6. doi: 10.1007/s00204-001-0286-6.
Goitrogenic effects of green tea extract catechins by dietary administration in rats
Y Sakamoto 1 , H Mikuriya, K Tayama, H Takahashi, A Nagasawa, N Yano, K Yuzawa, A Ogata, N Aoki
Affiliations

• PMID: 11808919
• DOI: 10.1007/s00204-001-0286-6

Abstract
The effects of green tea extract catechins on the rat thyroid were examined in a 13-week feeding study and subsequent 2-,4- and 8-week studies. Commercially available polyphenon-60 (P-60) which contains green tea extract catechins at 66.2% was used as a source of catechins. A basic diet containing different concentrations of P-60 was used for experiments. In the 13-week study, 10 rats of each sex were administered diets containing P-60 at 0 (control), 0.625, 1.25, 2.5 and 5.0%. Goiters were observed in the 13-week test. The mean thyroid weight of rats fed a diet containing 5.0% of P-60 (5.0% group) significantly increased to 444% of the control in males and to 304% of the control in females. Histological examinations of the thyroid of the 5.0% group revealed marked hypertrophy and/or hyperplasia of the follicles, some with depletion of colloid and some with rich colloid, and formation of a fibrous capsule. Slight hypertrophy of follicular cells was observed in male rats fed a diet containing 1.25% of P-60 (1.25% group) and female rats fed a diet containing 2.5% of P-60 (2.5% group). Degree and incidence of thyroid lesions were higher in males than in females in the 1.25, 2.5 and 5.0% groups. In the 2-8-week studies, five rats of each sex were given diets containing 0 (control) and 5.0% of P-60. In the 5.0% group, the mean thyroid weight in males significantly increased to 161% of the control as early as 2 weeks and increased to 357% of the control at 8 weeks. Histologically, these goiters were also associated with follicular cell hypertrophy/hyperplasia as in the 13-week study. The degree and incidence of thyroid lesions were higher in males than in females. These results indicate that dietary administration of the green tea extract catechins at high doses induced goiters in rats, and this may be due to antithyroid effects of catechins. In the 13-week study, the no-observed effect level (NOEL) of green tea extract catechins for F344 rats based on histological changes of the thyroid was considered to be 0.625% in males and 1.25% in females in the diet, respectively.

 

[not_James_Bond]

Green tea is just nasty, it was a thing some Years ago, it tastes absolutely disgusting, and a risk for thyroid.

 

[Mauritio]

How about black tee?

 

[Tristan Loscha]

Also, a lot of Teas are of questionable Quality; The leaves have no volume to them, and getting direct exposure to Biocides; they still use DDT and Fluoride containing Chemicals in poor Worldregions. Maybe the putative F residues are destroying the Hormones or interfering with iodine metabolism?

 

[DMF]

Biocides? Then I guess glyphosates too.
What about all the supposed health benefits?

 

[Tristan Loscha]

Biocides? Then I guess glyphosates too.
What about all the supposed health benefits?

Not sure; i read about them of course, but the construct of 'Phytonutrients' now seems rather iffy to me. I would see it as unindicated Medication and as Pharms with unknown mechanism of Action.

 

[LUH 3417]

What about quality tea? I’ve been ordering from teatrekker.com, they have very good jasmine and milk oolong tea...high quality, apparently from small ancient tea estates

 

[Tristan Loscha]

What about quality tea? I’ve been ordering from teatrekker.com, they have very good jasmine and milk oolong tea...high quality, apparently from small ancient tea estates

I hope they are good, but Coffee still has the better clinical track record for benefits iirc.

 

[Epik]

I remember seeing a post by @Travis where he claimed that the thyroid damage would mostly come from the fluoride often put on the green tea leaves. Maybe make sure it's clean and good quality green tea?

 

[golder]

I remember seeing a post by @Travis where he claimed that the thyroid damage would mostly come from the fluoride often put on the green tea leaves. Maybe make sure it's clean and good quality green tea?

Anyone know of a good brand that’s not likely to have fluoride?

 

[Whichway?]

I remember seeing a post by @Travis where he claimed that the thyroid damage would mostly come from the fluoride often put on the green tea leaves. Maybe make sure it's clean and good quality green tea?

The fluoride is not put on the plants. The tea plants accumulate it from the air and soil.

"Tea trees accumulate and store fluoride by absorbing it from the air and soil. Fluoride accumulates mostly in the leaves of the tea plant [2]. A substantial amount of fluoride is released during tea infusion. Because soluble fluoride is easily absorbed by the gastrointestional track, the bioavailability of fluoride from tea is close to 100% [7] which is similar to that from drinking water."
Risk Assessment of Fluoride Intake from Tea in the Republic of Ireland and its Implications for Public Health and Water Fluoridation

 

[not_James_Bond]

Green tea is vile,

 

[ecstatichamster]

Yes it suppresses thyroid function. .

 

[Dave Clark]

It could be anything, i would stay away from Tea and drink Coffee only.



. 2001 Dec;75(10):591-6. doi: 10.1007/s00204-001-0286-6.
Goitrogenic effects of green tea extract catechins by dietary administration in rats
Y Sakamoto 1 , H Mikuriya, K Tayama, H Takahashi, A Nagasawa, N Yano, K Yuzawa, A Ogata, N Aoki
Affiliations

• PMID: 11808919
• DOI: 10.1007/s00204-001-0286-6

Abstract
The effects of green tea extract catechins on the rat thyroid were examined in a 13-week feeding study and subsequent 2-,4- and 8-week studies. Commercially available polyphenon-60 (P-60) which contains green tea extract catechins at 66.2% was used as a source of catechins. A basic diet containing different concentrations of P-60 was used for experiments. In the 13-week study, 10 rats of each sex were administered diets containing P-60 at 0 (control), 0.625, 1.25, 2.5 and 5.0%. Goiters were observed in the 13-week test. The mean thyroid weight of rats fed a diet containing 5.0% of P-60 (5.0% group) significantly increased to 444% of the control in males and to 304% of the control in females. Histological examinations of the thyroid of the 5.0% group revealed marked hypertrophy and/or hyperplasia of the follicles, some with depletion of colloid and some with rich colloid, and formation of a fibrous capsule. Slight hypertrophy of follicular cells was observed in male rats fed a diet containing 1.25% of P-60 (1.25% group) and female rats fed a diet containing 2.5% of P-60 (2.5% group). Degree and incidence of thyroid lesions were higher in males than in females in the 1.25, 2.5 and 5.0% groups. In the 2-8-week studies, five rats of each sex were given diets containing 0 (control) and 5.0% of P-60. In the 5.0% group, the mean thyroid weight in males significantly increased to 161% of the control as early as 2 weeks and increased to 357% of the control at 8 weeks. Histologically, these goiters were also associated with follicular cell hypertrophy/hyperplasia as in the 13-week study. The degree and incidence of thyroid lesions were higher in males than in females. These results indicate that dietary administration of the green tea extract catechins at high doses induced goiters in rats, and this may be due to antithyroid effects of catechins. In the 13-week study, the no-observed effect level (NOEL) of green tea extract catechins for F344 rats based on histological changes of the thyroid was considered to be 0.625% in males and 1.25% in females in the diet, respectively.

My first thought is, what is considered 'high levels'? Just like cruciferous vegetables are condemned regarding thyroid, the levels needed to do that far exceed what is normally consumed in a diet. Similarly, a few cups of green tea/day may very well not be enough to enter in to the 'high level' category needed to deem green tea goitrogenic. Tea drinking can be rotated with other types of tea like Mate, rooibos, herbal teas, etc., as well to get a varied spectrum of antioxidants and trace nutrients.

 

[Tristan Loscha]

My first thought is, what is considered 'high levels'? Just like cruciferous vegetables are condemned regarding thyroid, the levels needed to do that far exceed what is normally consumed in a diet. Similarly, a few cups of green tea/day may very well not be enough to enter in to the 'high level' category needed to deem green tea goitrogenic. Tea drinking can be rotated with other types of tea like Mate, rooibos, herbal teas, etc., as well to get a varied spectrum of antioxidants and trace nutrients.

I believe that the low volume and high surface area of tea leaves leads to an increase of surface area that pesticides can cling to.

 

[ecstatichamster]

I was a big tea drinker of the finest teas in the world.

I found out that the Chinese and others who drink tea will reuse the loose leaves for a number of cups. It is for this reason that I think that the effects are relatively mild. They are only using a small number of leaves and re-using them a number of times over the day.

 

[Vins7]

Is drinking 3-4 cups of green tea a day have a possible negative effect on Thyroid Levels ?
I believe my "male hot flashes" began around the same time I started drinking green tea.

What do you mean with male hot flshes?