Twenty percent of American workers are night-shift workers, a number which is growing at a rate of about 3 percent every year. These workers are known to be at higher risk for accidents, sleep disorders and psychological stress.
Scientific evidence suggests their disrupted circadian rhythms can also raise their likelihood of obesity, cancer, reproductive health problems, mental illness and gastrointestinal disorders. The International Agency for Research on Cancer, a unit of the World Health Organization, has actually declared that shift work is "probably carcinogenic to humans."
Night-shift workers:
- Have a 40 percent to 50 percent increased risk of heart disease
- Are 50 percent more likely to be obese if they get less than five hours of sleep per day
- Have higher rates of miscarriage, pre-term birth and low birth-weight babies
- Show significantly increased rates of breast and colon cancer