According to The American Medical Association, "stress is the basic cause of more than 60% of all human illness and disease." As someone who used to get "stressed out" often, I am not surprised that these numbers are not higher.
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If you click on this link, you will be redirected to the Heart Math website. Be sure to read about the 5 facts associated with stress and how it affects the body.
Here are some simple tips that worked for me to reduce stress:
Tip 1: eat healthy and maintain a well-balanced diet (daily)
Tip 2: get at least 7 hours of rest a night
Tip 3: learn basic meditation techniques (an iPhone app that I use is Calm)
Tip 4: try yoga and deep breathing exercises
Tip 5: keep a journal