Stress weakens self-control

When you're stressed, the sympathetic nervous system takes over - also referred to as the "fight or flight system." It enables your body to respond quickly to perceived threats or stress. When this happens, your heart rate goes up and stays high, leading to feelings of anxiety and anger.

People with high levels of stress are more prone to poor self-control and focus. Stress will also shift your brain to a reward-seeking state: Whatever will make you happy at the moment will become a fixation. That is why people who are stressed are more likely to smoke, gamble, play video games, surf the internet or watch TV. The most effective stress-relief strategies include exercising, reading, listening to music, and spending time with loved ones.