Lack of sleep causes changes to the body's cholesterol and may contribute to the development of cardiovascular disease, a new study has found.
Research conducted by the University of Helsinki has shown that long-term sleep loss is responsible for slowing down cholesterol metabolism, leading to a heightened risk of cardiovascular disease and illness.
Cardiovascular disease is Britain's biggest killer, responsible for 155,000 deaths each year - or one person every three minutes.
The study found that sleep deprivation over time increases the risk of atherosclerosis, a condition where arteries become clogged up with fatty substances, causing blood vessels to harden and narrow.
The Sleep Team Helsinki research group conducted a number of laboratory-induced sleep loss experiments, which they compared to a Finnish population study charting the lifestyles and heart health of 2,221 participants throughout their childhoods.
By comparing blood samples with the population data, the study found that the genes which regulate and transport cholesterol around the body are less effective in people suffering from sleep deprivation that those getting sufficient rest.
The results help to explain why cardiovascular disease is more commonly observed in sleep-deprived people, and builds on previous research into how sleep affects the immune system, appetite and the risk of inflammation.
Vilma Aho, a member of the research team, said the research had helped improve medical understanding of how sleep loss impacts negatively on the body's ability to function.
"In this case, we examined what changes...could be partially responsible for the elevated risk for illness," he said.
"Just one week of insufficient sleep begins to change the body's immune response and metabolism. Our next goal is to determine how minor the sleep deficiency can be while still causing such changes."