Insufficient sleep significantly impacts health, particularly in relation to cancer and cardiovascular conditions. Just one night of poor sleep, like four hours, results in a dramatic 70% decline in natural killer cells, which are vital for combating cancerous growths. Moreover, a global study surrounding daylight savings time shows that losing just one hour of sleep correlates with a 24% rise in heart attack incidents, while gaining an hour leads to a 21% decrease, illustrating the body's extreme sensitivity to sleep variations. Therefore, consistent sleep is crucial for maintaining immune and cardiovascular health.