'Skepticism about life' induces production of chemicals in blood that can raise the risk of hypertension, heart attacks and strokes, according to a study.
Earlier researches have proved that stress is as strong a risk factor as obesity, smoking and high cholesterol in causing heart attack.
Researchers have now come up with a finding that cynical distrust can also elevate the risk of heart problems and suggest, "Our behavior and emotions directly affect our health."
During the study, about 7,000 men and women aged between 45 and 84 were asked to complete two sets of questionnaires. The first one was based on their social background, depression and stress and the second one on how cynical their outlook was in general.
Nalini Ranjit of the University of Michigan, and colleagues used the data from the two completed questionnaires for the research.
Blood samples from all the participants were taken and scanned for three different chemicals - IL-6, C-reactive protein and fibrinogen, as these indicate inflammation.
It was found that the blood of people who were severely stressed had two of the chemicals whereas those with depression had one of them. However in people who were classed as having an outlook of cynical distrust, all three chemicals were found.
"The strongest and most consistent associations were observed for cynical distrust, which was positively associated with all three inflammatory markers," said Dr Ranjit.
Factors such as body weight, social background and diabetes also seemed to affect the concentration of these indicators.
Researchers conclude that psychosocial factors like stress and cynicism causes habits such as smoking and over eating in people, which in turn lead to a host of problems.
This study published in the British Medical Journal also finds that, hostility can cause damage to the lung, reducing its capacity.
Vicky Styman, cardiac nurse at the British Heart Foundation, said: "There is insufficient evidence to say that stress, depression or other emotions are significant risk factors for heart disease, although they are often associated with it. One difficulty is that emotions are subjective."
"It is particularly difficult to define if someone is cynical and measure what impact this has on their likelihood to develop disease.
"As the authors of this study acknowledge, psychological factors such as stress can often lead to unhealthy behaviours, including smoking, eating an unhealthy diet and physical inactivity - all of which are established risk factors for heart disease."