Green Tea Side Effects

Are there any side effects such as "restless legs" from drinking green tea?

Tea, black or green, is a nerve and circulation stimulant. The nervous and circulatory systems are involved in "Restless Leg Syndrome" which is twitching of the leg, especially at night.
Tea causes a deficiency in thiamine (vitamin B1), which is necessary for the nervous system. An excess of tea causes muscle weakness.
Tea raises stomach acidity, causing problems for those prone to ulcers or gastric reflux. It also reduces absorption of iron and protein.