Mood swings can be a disruptive and upsetting part of life; they may be caused by a number of different things, including hormonal imbalances, poor diet, or simple stress. As a result, the best way to stop mood swings can vary for different people, so it is helpful to try to first identify the causes of mood swings, and do what you can to avoid them. If the mood swings do not seem to have a particular cause, but are seemingly occurring at random, there are still things you can do to stop them. The first is to make a conscious effort to stop your thought pattern; the second is to physically remove yourself from the situation, and take some deep breaths or go for a walk.
It is not easy to stop mood swings; it will certainly take some effort on your part. Some people find success in keeping track of their thoughts at all times, not just when mood swings are occurring. Writing in a journal or practicing meditation can help to indicate certain repeated thoughts that my be causing bad moods, and can also be a good way to deal with those thoughts and move on. Or, if they arise throughout the day, actually saying "stop" to yourself and distracting yourself with something else can help to stop mood swings.
You might be amazed at how effectively a simple distraction can stop mood swings in their tracks. If you are feeling stressed and upset, simply getting up and stretching, taking a walk, or taking some deep cleansing breaths can help to stop panic, anxiety, or anger from worsening. Often, this is all that is needed to gain some perspective and stop the mood swing. Some people find that repeating a positive affirmation to themselves when they are feeling upset will also help to prevent mood swings, and help them to feel more in control of the situation.
Lifestyle changes can also help to stop mood swings, particularly if they are occurring seemingly for no reason. Eating a lot of sugar, or stimulants and/or depressants such as coffee or alcohol, can all make mood swings more frequent because they affect the nervous system as well as the blood sugar levels in the body. Getting regular exercise can help to regulate the body, and can also promote the release of mood-stabilizing endorphins in the brain. In addition, getting enough sleep at night can help to make moods less volatile during the day.