Smile away stress for long-term health

Adults who fail to maintain positive moods such as cheerfulness or calm when faced with the minor stressors of everyday life appear to have elevated levels of inflammation that can undermine their long-term health, says a study.

Inflammatory responses are part of the body's ability to protect itself via immune system. However, chronic -- long-term -- inflammation can undermine health and appears to play a role in obesity, heart disease and cancer.

"A person's frequency of stress may be less related to inflammation than responses to stress," said researcher Nancy Sin from Pennsylvania State University in the US. "It is how a person reacts to stress that is important.” In the short-term, with illness or exercise, the body experiences a high immune response to help repair itself.

However, in the long term, heightened inflammatory immune responses may not be healthy. Individuals who have trouble regulating their responses may be at risk for certain age-related conditions, such as cardiovascular disease, frailty and cognitive decline, Sin said.

The study published in the journal Health Psychology and involved 872 participants who reported daily stressors and emotional reactions for eight consecutive days. Blood samples of participants were obtained during a separate clinic visit and assayed for inflammatory markers.

The researchers evaluated a person's emotional response on days when they experienced stressors, and compared it to days when they did not. "We calculated reactivity scores to see how participants generally reacted to stressors.”