The increased risk of breast cancer seen in Finnish flight attendants may be due to disruption of sleep-wake cycles and a consequent reduction in melatonin production.
Researchers found that flight attendants had a 1.87 relative risk of breast cancer after working in the industry for a mean of 13.9 years.
Jet lag is associated with disturbances in the pineal gland in the brain and the pineal gland secretes melatonin so that if you have jet lag you have reduced melatonin secretion.
Reduced melatonin secretion has, in turn, been linked to breast cancer.
The Lancet August 22, 1998;352:626
Dr. Mercola's Comment:
The ideal solution would be to allow the body to normalize these levels. I suspect that there may be some benefit of taking melotonin in jet lag or shift workers.
One way you can increase your melatonin production is to make certain you sleep in an absolutely dark environment.
If you happen to wake up, do NOT turn on any light as that will suppress your body's own melatonin production. This is the hormone of the night and will only be made in complete darkness.