How much does your thinking actually effect how you feel?

Lately I have become very aware of how my thinking effects physiological changes in my body. Like a racing heart, or just a washed out feeling. Which can later result in tiredness.

Surely then conversely this can work in the positive too?

So on that score, how does your thinking manifest in your day to day life. Are you aware that it can create a better physiology? And subsequently a better day in all? Some people seemed to have a mastered expertise in thinking, while others, such as I have to keep a strict reign on my own mind. Has your thinking at times destroyed your life? Any sharing appreciated.