Stress messes with your brain and it causes many changes to the layers of the brain. Due to stress, some regions of the brain become hyperactive and others shrink, the level of the receptors in the brain is also changed and this starts affecting normal body functions. Since your body isn’t designed to go well with these changes you start feeling unwell. In fact, very high levels of stress hormones in the body can cause serious consequences such as heart diseases, fatigue, digestive problems, headaches, weakened immune system, and muscular tension.