Based on conversations with friends and associates I have found the relationship between human health and jet noise difficult to communicate. Based on several studies the human body's negative connection to jet noise is made with the stress hormone cortisol as secreted by the adrenal glands. Under normal circumstances cortisol is responsible for the 'fight or flight' response. A problem develops when this hormone is stimulated over a period of time. An instantaneous secretion of cortisol protects humans from accidents and disaster. A prolonged secretion causes stress related damage and disease.
· Impaired cognitive performance
· Suppressed thyroid function
· Blood sugar imbalances such as hyperglycemia
· Decreased bone density
· Decrease in muscle tissue
· Higher blood pressure
· Lowered immunity and inflammatory responses in the body, slowed wound healing, and other health consequences
· Increased abdominal fat, which is associated with a greater amount of health problems than fat deposited in other areas of the body. Some of the health problems associated with increased stomach fat are heart attacks, strokes, the development of metabolic syndrome, higher levels of "bad" cholesterol (LDL) and lower levels of "good" cholesterol (HDL), which can lead to other health problems!
Conditions listed above are epidemic in our society. The relationship of these conditions is well know.
Go to this site for additional information: http://stress.about.com/od/stresshealth/a/cortisol.htm
I tend a hobby farm and use power tools. Part of my work [aka play] process involves protection of life, limb and hearing. I use two layers of hearing protection, both OSHA approved. First I install foam plugs followed by muffs. This procedure negates most sounds to nearly zero. This procedure did not reduce jet over flight noise. I believe sound waves created by jets enter the body differently and affect the organs and adrenal glands in a more fundamental way.
This is serious and dangerous to us humans and presumably to other earth creatures.