UPPSALA, May 26, 2025 — New findings suggest that just three consecutive nights of poor sleep can trigger inflammation-related changes linked to cardiovascular disease. In a crossover study of 16 healthy young men, limiting nightly rest to approximately 4¼ hours for three nights led to elevated blood levels of 16 proteins associated with cardiac risk – including stress, interleukin, and chemokine markers.
The study was conducted at Uppsala University in Sweden and published in the journal Science Advances.
Although regular high-intensity exercise did show some positive effects on protein levels, it was not sufficient to fully reverse the inflammation induced by sleep deprivation.
Sleep restriction was also associated with a blunted rise in beneficial proteins such as IL‑6 and BDNF compared to participants who had normal sleep periods of around 8½ hours.
Experts caution that while this biomarker‑based study was limited to young men, the findings highlight how quickly physiological harm can begin. Further research is needed to understand impacts on older adults and women. Study co‑author Chen commented that the results are “not entirely surprising,” noting that poor sleep adversely affects endocrine, immune and cardiovascular systems.
Broader research consistently links short sleep – typically under seven hours – to higher risks of hypertension, coronary heart disease and metabolic dysfunction. Long-term inadequate sleep is associated with up to a 20‑30% increased risk of cardiovascular disease. Meanwhile, some studies suggest that “catch‑up” sleep on weekends may reduce heart disease risk by about 20%, though this strategy may not fully compensate for regular sleep loss.