For the past two decades there has been much controversy in the scientific field about whether or not fasting is beneficial to one's health. A few years ago researchers began to study fasting and the benefits it holds. In the end, they uncovered many benefits, but the main focus was the immune system. To the researchers surprise, fasting for as little as two or three days can re-boot or thrive one's immune system. It is said that fasting “flips a regenerative switch.” This paper examines how fasting as little as two days in the week can have an impact on one's immune system. It uses online sources and a study to prove that fasting protects against cancer cell formation, reduces free radical damage, and reduces inflammation in the body.