Sugars (refined/processed) are classified as drugs and therefore have withdrawal-symptoms. Neither is Pepsi beneficial to helping you to calm your emotions. Like all drugs they have a period of time of withdrawal-symptoms until addiction can be eliminated. I cannot stress enough how important it is to avoid all of these unhealthy substances (they factually do have an effect on the emotions).
You are correct that you do not have full control over your thoughts/emotions when you find yourself in a state of outburst. This is partially a result of the withdrawal-symptoms of going without certain mind-altering substances (particularly if you are unable to handle quitting cold-turkey). The phenomenon is not limited merely to drugs/alcohol but also extends to certain types of food, certain smells/odours/gases, exposures to certain types of frequencies/radiations, etc.
The onslaught of negative thought-intrusion can be very difficult to resist. I used to be psychotic myself so I am fully aware of negative-emotions having an over-powering effect on how you feel and react to your surroundings. Initially, resistance against letting negative emotions control you will be difficult, but with enough practice, such as through martial arts style meditation-like visualisation, you can learn to eventually control your emotions instead of letting them control you. You may as well start right now, any time you catch yourself starting to feel anger or any other kind of negative emotion, finding devious thoughts entering into your mind, try closing your eyes and breathing deeply whilst mentally "commanding" the emotions within you to convert into more peaceful thoughts and feelings. Repeating this mental-exercise at least three times a day, each and every single day, from this day henceforth, should have an effect at helping you to reduce your anger-levels, and warding off any phenomena that might feel like spirit-possession.
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