See What Anger Does to Your Brain and Body.

Anger is a normal emotion that allows you oppose someone or something which you feel has deliberately done you wrong. Anger can be a good feeling, in that it provides a channel for you to let out negative feelings, or motivates you to find solutions to problems in your life. However, an uncontrolled anger often leads to arguments, physical fights, physical abuse, assault and self-harm. 

An uncontrolled anger can lead to the following:

• Increased heart rate and blood pressure: When you are angry, your heart rate and blood pressure rises because of the increased levels of adrenaline and noradrenaline.
  These hormones are released by the adrenal glands in response to fright or stress. The recurrent increase in heart rate and blood pressure puts your heart at risk. According to Chris Aitken, two hours after an angry outburst, the chances of developing a heart attack doubles. He also said, “Repressed anger — where you express it indirectly or go to great lengths to control it, is associated with heart disease.”
  
  
• Increased Risk of Stroke: If you always lose your cool and lash out at people or things around you, then you might just be increasing the chances of having stroke (cerebrovascular accident). In a certain study, researchers found out there was three times higher chances of blood clot to the brain or bleeding within the brain during the two hours after an angry outburst.
  
  
• Headache: During an angry outburst, impulses are transmitted to the blood vessels, causing them to dilate (widen) and constrict (narrow). The continuous dilation and constriction of the blood vessels lead to headache.
  
  
• Weak Immune System: Your immune system gradually weakens as you always explode. In a particular research, some scientist from Harvard University discovered that in healthy individuals, by just remembering an angry experience from their past, there was a 6hr drop in the concentration of antibody immunoglobulin A.
  
  
• Increased anxiety:  Anger and anxiety go hand-in-hand. if little things get you angry, then your anxiety level will increase. "In a 2012 study published in the journal Cognitive Behavior Therapy, researchers found that anger can exacerbate symptoms of generalized anxiety disorder (GAD), a condition characterized by an excessive and uncontrollable worry that interferes with a person’s daily life. Not only were higher levels of anger found in people with GAD, but hostility — along with internalized, unexpressed anger in particular — contributed greatly to the severity of GAD symptoms."
  
  
• Depression: Anger has been associated with depression, especially men.
• Anger can shorten your lifespan. Happy people live longer. “Stress is very tightly linked to general health. If you're stressed and angry, you'll shorten your lifespan,” says Fristad. A University of Michigan study done over a 17-year period found that couples who hold in their anger have a shorter life span than those who readily say when they're mad.

Below is an infographic that gives you insight into the events that occur whenever you are angry.

How you can control your anger

"Simple relaxation tools, such as deep breathing and relaxing imagery, can help calm down angry feelings. Some simple steps you can try:

• Breathe deeply, from your diaphragm; breathing from your chest won't relax you. Picture your breath coming up from your "gut."
• Slowly repeat a calm word or phrase such as "relax," "take it easy." Repeat it to yourself while breathing deeply.
• Use imagery; visualize a relaxing experience, from either your memory or your imagination.
• Practice these techniques daily. Learn to use them automatically when you're in a tense situation"
• Use a little humour: "Silly humor can help defuse rage in a number of ways. For one thing, it can help you get a more balanced perspective"
• Change your environment: Sometimes it's our immediate surroundings that make us angry. Problems and responsibilities can weigh on you and make you feel angry at the "trap" you seem to have fallen into, and with people you feel are responsible for the trap.
  Take a little break. Make sure you have some "personal time" scheduled for times of the day that you know are particularly stressful. One example is the working mother who has a standing rule that when she comes home from work, for the first 15 minutes "nobody talks to Mom unless the house is on fire." After this brief quiet time, she feels better prepared to handle demands from her kids without blowing up at them.
• Communicate better: Most times, angry people tend to jump to and act on conclusions that are often inaccurate. If you find yourself in a heated argument, don't say the first thing that comes into your head. Simply pause for a while and think through your responses before saying them. Listen to what others are saying, and then speak gently and carefully.

In conclusion, don't allow anger rule your life, for your life is the most precious gift you have. Make good use of it by controlling all your emotions, especially anger.

Sources:

1. https://www.apa.org/topics/anger/control.aspx
2. https://www.everydayhealth.com/womens-health/managing-your-temper.aspx
3. http://www.researchgate.net/publication/221721892_The_role_of_anger_in_generalized_anxiety_disorder
4. http://www.ncbi.nlm.nih.gov/pubmed/25389190
5. https://www.everydayhealth.com/news/ways-anger-ruining-your-health/
6. https://www.nicabm.com/how-anger-affects-the-brain-and-body-infographic/