In most of the cases, yes, it can be controlled. Sometimes you simply need to change your outlook. If your blood pressure rockets simply because your child refuses to cooperate, instead of getting into a rage, try to understand why the child is not cooperating and how a common ground can be achieved. Similarly, if a situation is making you angry, maybe you need to look at things from a different perspective. You can regularly meditate. You can avoid highly spicy foods. Exercise everyday so that toxicity is released. Maintain a healthy lifestyle. Try to look at positive things in life.