Stress can dramatically weaken the body’s defences against disease, leaving people who lead such lives with immune systems ten years ‘older’ than they should be, says a report.

The University of California said its findings shows just how much stress can help speed up the ageing process, particularly in women. The research team assessed the condition of DNA structures called telomeres among mothers with stressful lives. Telomeres, which act as protective ‘caps’ on the end of chromosomes, are vital to a healthy immune system.

The scientists found that those in women with the highest levels of stress had undergone the equivalent of ten years’ additional ageing.