Hey I came across this article on what weakens one's immune system which I thought was interesting:
http://healthmad.com/health/what-causes-a-weak-immune-system/$this->bbcode_second_pass_quote('', '[')b]Poor Diet: Poor diet for a long time can weaken the immune system. Foods with chemical additives, pesticides, preservatives damage the immune system and that can cause to develop any chronic disease. When our body lacks nutrition, we’ll have a weak immune system.
Overdose of Sugar: Excessive consumption of refined sugar can reduce the ability of white blood cells to kill germs. Consuming high amount of sugar has a bad effect on the immune system.
Excess Alcohol: Excessive drinking of alcohol harms the immune system. Just like sugar, too much of alcohol reduces the ability of white blood cells to kill germs. Also, high dose of alcohol produces an overall nutritional deficiency, depriving the body of valuable immune- boosting nutrients. How does alcohol affect the body?
Lack of Sleep: A good sleep essential for our body to restore itself. This helps to rebuild immune system. Without adequate sleep, immune system becomes weak because it doesn’t get the chance to rebuild.
Stress: Stress suppresses the immune system functions. Long term stress is extremely bad for immune system. Research shows that chronic stress lowers the number of white blood cells.
Dehydration: This means the body in note getting enough fluid. Dehydration can cause many medical problems. To work our immune system properly the sufficient amount of water is very essential.
Medication: Overuse of prescribed or non-prescribed medications can damage immune system. Drugs are major toxins that we put into our body. Adding to this, prolonged use of antibiotics weakens the immune system.
Radiation Exposure: Chemical exposure, UV, and radiation exposure- all these damage the immune system.
Unhygienic Lifestyle: A good hygiene care is very important to maintain a strong immune system. Too much exposure to germs may stress the body beyond what it could handle. A good hygienic life is best to avoid infection and keep a strong immune system.
Inactivity: Exercise is very important to keep a good immune system. Exercise helps to increase the blood flow which helps cleansing the body of certain toxins and waste products. Check out the 20 simple tips to stay fit. Lack of exercise slows down this process and it results a weak immune system. Obesity can also lead to a weak immune system.
A lot of this is common sense, but identifying which of the above might be useful. Good reminders at any rate.
I think work stress was the trigger when I got shingles.