Oolong tea is famous for the great benefits that it provides for human body as well as mind. The compounds present in it are considered as the great healing substances from ancient times. For example, the tannin content present in it helps to balance the cholesterol in human body. It also includes components that help to increase the metabolic rates. These components then assist in reducing the weight naturally by increasing the burning rates of fats present in the body. There are certain side effects for oolong tea that each of us should be aware of. However, each and everything that you have in excess can affect your bodies harmfully. Tea is naturally made carefully processed and therefore the side effects can cause little or harm to you. The increase in level of caffeine is the primary side effect that can happen due to the excess intake of oolong tea. There is more content of caffeine in coffee as well as chocolate. Therefore, it is not certain that the caffeine drawback happens with everyone. However, in certain cases higher amounts of caffeine content in the body can create sleeping problems, makes you resistant towards insulin, and can also decrease your metabolism. In certain very rare cases, it can even cause caffeine toxicity, which is also called as Hypokalimia. This stage can even result in death. In addition to all these, for pregnant ladies it is advisable to control the intake of caffeine through any forms. For example, tea, sodas, coffee or any other product that contains caffeine. Higher caffeine contents in a female body can even cause miscarriages as well as small infants. Apart from all these caffeine is a known natural diuretic. Finally, to point out caffeine contains some traces of oxalates, which can even lead to kidney damages and other chronic kidney related disorders. Even though tea is a natural product, the negative effects are not justified. The major cause of faster weight loss in human body is because of its tannin polyphenol content. However, this creates a higher risk to the internal organs of the human body specifically the kidneys, liver and the intestines. To sum up certain compounds present in the oolong tea can even cause irreparable damages to the human body. Hepatoxity, infant leukemia is some of those irreparable damages. Its excess usage can even lead to death. Hence, the word caution has to be always remembered before taking excess of caffeine.