Unable to fault,
A good starting point for academic research in this area is the Journal of Occupational & Environmental Medicine, which can be searched on-line at their website
OEM Online Some papers are available in full [e.g. Karlsson,Knutsson & Lindahl, 2001, An association between shiftwork and the metabolic syndrome.] Others are available only in abstract but if you contact the journal and explain your research interest no doubt they will accept your subscription. For the less academically minded, you may wish to visit the following informative sites:
Shift work link to heart disease
Night shift link to heart problems
Nightshifts linked to heart disease
Nightshifts 'increase breast cancer risk.'
The Transport and General Workers Union are also informative [at last!]
The Working Time Regulations - A TG&W Guide
Drawing conclusions from academic studies is notoriously difficult as there are always conflicting findings and disagreement over the significance of particular figures, or even the methodology itself. Nevertheless, anyone familiar with research papers will soon find a central thread leading to the conclusion that shift work, particularly night shift, is extremely hazardous to the health.
In my own case I continue to suffer from increased tri-glyceride levels that are non-responsive to dietary intervention. Only medication keeps the levels under control. Studies have indicated that night work leads to increased tri-glyceride levels
that do not necessarily return to normal after night work ceases. I did several years of permanent nights in the seventies to pay for life's essentials and then paid the price in the nineties when I had a heart attack and subsequently a bypass operation to restore the blood supply to my heart.
BTW, I mentioned in an earlier post that of the five people in my section who are over fifty, three of us suffer from vascular disease. In view of the research, it is noteworthy that all three worked long periods of night shift when we were younger. Of the remaining two, neither have ever worked extended night shifts and one, who still enjoys BP readings of 115/65, has never worked nights at all.
**********************************
Through difficulties to the cinema