Call centers and other outsourced businesses employ more than 1.6 million men and women in India, mostly in their 20s and 30s.
About 32 percent of respondents complained of sleep disorders; 25 percent had digestive troubles; and 20 percent reported eyesight problems.
The survey covered 1,749 employees at 19 outsourcing companies.
Many call center employees admitted to having many of these ailments, but they refused to be named or identify their employer, The Associated Press reported.
Sleep and digestive disorders can lead to hypertension, diabetes and heart disease.
India's case is alarming because of the sheer number of people affected and the factors that make them vulnerable to these diseases, said Ravi Kasliwal, a cardiologist at New Delhi's Indraprastha Apollo Hospital.
These include India's fat-rich diet, genetic factors make them highly vulnerable to diabetes, and abdominal obesity that gives rise to insulin resistance and heart disease.
