Some people seem to thrive on just a few hours of sleep, like former British PM Margaret Thatcher, who reportedly slept only four hours a night. However, for most of us, that would lead to grogginess, poor focus, and health issues. Natural short sleepers are a rare group of people who function well on just 4 to 6 hours of sleep, thanks to genetic mutations that improve sleep efficiency. In a 2025 study, one woman in her 70s lived a healthy, active life despite consistently sleeping just six hours.  However, most people who get little sleep aren't naturally wired that way, they're just chronically sleep-deprived.  Long work hours, stress, and hustle culture lead many to ignore their body's need for rest.  Over time, this builds sleep debt, increasing risks for obesity, heart disease, diabetes, and poor mental performance. Some try to catch up on sleep over the weekend. While naps and extra rest can help temporarily, research shows it doesn't fully reverse the damage.  Irregular sleep patterns may even pose long-term health risks.. ISleep needs vary based on age, health, and genetics. For most adults, 7-9 hours a night is essential. Sleep isn't a luxury, it's a critical part of staying healthy.