People who develop sepsis after long-term consumption of a Western diet, low in fibre and high in saturated fat and sucrose, are vulnerable to severe aggravated disease, a study released on Monday has suggested.

Medical researchers at the Stanford School of Medicine in the US have through studies on laboratory mice found that a Western diet influences immunity and drives sepsis towards more severity and a lower chance of survival.

Sepsis is a leading cause of critical illness and deaths worldwide, driven by a deleterious immune response to the spread of micro-organisms in the blood and other organs that can result in organ failure and a life-threatening fall in blood pressure.

Although doctors have for decades battled sepsis with antibiotics and other medicines to correct its associated physiological disruptions, the factors that contribute to the deleterious immune response and the outcome of sepsis remain a puzzle.

Now, microbiologist Denise Monack and her colleagues at Stanford have found that mice fed on a Western diet for two weeks display higher inflammation levels and a suppressed immune state, called immuno-paralysis, during sepsis.

Their findings, published on Monday in the US journal Proceedings of the National Academy of Sciences, show that mice fed a Western diet have more severe sepsis and increased mortality compared with mice on a standard diet.

The researchers also observed differences in immune responses, including differences in the numbers of a class of infection-fighting cells called neutrophils, in the two groups of mice.

“Western diet is reprogramming the immune status and response to the sepsis,” the researchers wrote in their paper.

They have highlighted that obese people are likely to exhibit chronic inflammation. But, they have said, more studies will be needed to unravel how diet-triggered changes in the immune system translate into the body’s response to sepsis.

Nearly a decade ago, another group of researcher in the US had conducted experiments on mice and alerted the medical community about high-fat diets causing the immune system to significantly exaggerate the inflammatory response to sepsis.

The laboratory findings, the latest researchers say, are consistent with longstanding observations that the mortality rates from sepsis in people with extreme obesity are significantly higher than the mortality rates from sepsis among thin individuals.

However, Monack said the findings may already have implications for both the prevention and perhaps for the treatment of sepsis.

“For prevention, doctors could prescribe high-fibre and low-fat diet before a patients is scheduled for surgery,' she told The Telegraph. “In terms of treatment, there are likely specific metabolites or components of the diet that could serve as biomarkers that doctors could look for in the blood of sepsis patients that would indicate that they are at high risk of severe sepsis and may need more aggressive treatment.”