(HealthDay News) — Recurring emotional stress may trigger a stronger biochemical response in overweight people, possibly increasing their risk for chronic illnesses such as heart disease and type 2 diabetes, according to new study published in Brain, Behavior, and Immunity.
On 2 consecutive days, Christine McInnis, from Brandeis University’s Laboratory for Biological Health Psychology in Waltham, Massachusetts, and colleagues placed people of various body sizes in stressful situations, including a very unfriendly job interview and a difficult oral math exercise.
Saliva samples were then taken to examine how the stress affected the person’s body chemistry.
Overweight people repeatedly placed in a stressful situation exhibited increasing amounts of interleukin-6 (IL-6) in their saliva, the researchers found. Normal-weight people did not exhibit this escalation in IL-6 levels when exposed to repeated stress.
Lean people started out with lower IL-6 levels than obese people, but both lean and obese participants exhibited similar amounts of biochemical response to stress on the first day.
However, overweight or obese individuals exhibited an IL-6 response on the second day nearly double that of their response the day before. By comparison, the second-day response of lean people was the same as it was their first day.
“You already are at risk for these diseases by being obese, and then you have these magnified responses that further exacerbate your risk,” Brandeis told HealthDay. This indicates that obese people are physically affected by repeated stress much more dramatically than people at normal weight, and recover from stress more slowly, she added.