|If you drink green tea 24/7 you don't have to wonder if your thyroid is sluggish and your belly growing.|
The authors, Abulfadle K. A., Bakhaat G. A., Shaik R. and Tantry B. A., studied the effect of excessive green tea intake on body weight and serum thyroid hormones in male mice and compared their results to what happens if the rodents are fed only fluoride and caffeine.
To confirm the ill effects of excessive green tea intake on thyroid gland, the scientists measured both, the level of thyroid hormone and the weight of the thyroid of their 30 male albino mice who were divided into five groups.
- Control (C) group (6 mice) receiving distilled water.
- Green tea (GT) treated group; 6 mice were given a 5 gm% tea hot water extract as their sole water supply (that's similar to you drinking 1-2 L or more).
- Fluoride (FL) treated group, 6 mice were given fluorine excess solution as their only water supply.
- Caffeine (Caf) treated group, 6 mice were treated with caffeine (6.25 mg/kg ip | that's only 0.51 mg/kg body weight for a human and thus not exactly much).
- Propylthiouracil (PTU) treated group, a substance of which we know that it interferes with the synthesis of thyroid hormone, 6 mice were treated with PTU (10 mg/kg ip).
|Green tea triggers weight loss only in overweight subjects (Hase. 2001).|
|Figure 1: Effect of green tea, fluoride & caffeine on final body weight, T3 and T4 | data is expressed in % of control; *P < 0.05 compared to control. ***P < 0.001 compared to control. #P > 0.05 compared to control (Abulfadle. 2015).|
- Abulfadle, Khaled Abdelfattah, et al. "Effect of Excessive Green Tea Versus Fluoride and Caffeine on Body Weight and Serum Thyroid Hormones in Male Mice." Journal of Physiology and Pharmacology Advances 5.2 (2015): 565-573.
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