The body is wired to shift it's state this way. When you take deep breaths the body reads this as being in a safe environment. This means it can relax, because there is no need to provide anymore of the stress hormones. I can make a simple analogy. Imagine a country at war. They have to cut down funds from education and health to improve military. Same with the body. When the body is at war, it cut's down on the good hormones and make bad hormones, that helps the body in stress situation, only this lowers your vibration, as stress is a low frequency emotion. Hope it makes sense. Thanks for the feedback!