In his speech that titled ” Your genes are not your fate “, Dean Ornish says that changing the lifestyle could change the genes inside human body. The change of the genes does not require much time to be seen. Changing the food habit, doing more exercises, and avoiding stress give the brain more blood flow and more oxygen, and as a result, the brain gets measurably bigger. To motivate the brain to grow more cells, it is important to have some type of food such as chocolate, tea, and blueberry. In addition to that one should avoid some food that decreases the brain cells such as saturated fat, sugar, and cocaine. The body cells could be increased by conducting new positive habit, and eliminating negative ones. However, it has been proven that Oxygen is one of the secrets of human lives. Getting the amount that one’s body needs from oxygen reduces the desire for the food, and vice versa. Some studies show that body’s cells with the needed amount of oxygen live for longer time.