One side effect of Green Tea is that if you drink green tea on an empty stomach, you will feel sick, nauseous or dizzy.
The reason is that the better the green tea, stronger it is to your stomach in aiding digestion and more effective in lowering the blood sugar. If you are hungry, it will cause nauseous, stomach pain, and dizzy (blood sugar get too low).
Just don`t drink green tea on an empty stomach. If you do and feel sick, just eat a bread or an apple, you will feel better right away.
The other side effect is that after taking green tea, you are too-hype and cannot sleep. The better the green tea, the stronger the effect will be.
Green tea contains at least two stimulating chemical compounds (one of them is caffeine). Just don`t drink green tea in the afternoon or at least 5 hours before you go to bed. If you do drink green tea and cannot sleep, eating some bread helps a little bit.
If you have other unpleasant feeling after taking green tea, just cut down consumption of green tea or take tea at another time (after a meal).