“Can I train myself to get by on less sleep?” As a sleep clinician, I hear this question often. Here’s what my professional experience says, along with the science to back it up. Read on to learn why it’s a mistake to think you can train your body to need less sleep, as well as what you should do instead.
1. Sleep isn’t optional. It’s essential. You can’t "hack" your biology. No amount of training or willpower can change the fact that your body needs consistent, sufficient rest to function properly. Sustained sleep restriction leads to cognitive decline, emotional instability, and physical health issues (no matter how “adapted” you feel).1
2. Just because you feel “fine” doesn’t mean your brain is functioning at its best. Many people think they’ve adapted to less sleep, but in reality, their performance, mood, and cognitive abilities suffer (often without them realizing it). While you may normalize sleepiness, research shows your performance will continue to decline with sleep loss, even if you stop noticing it.2
3. Most people need 7-9 hours of sleep. If you think you’re the exception, you’re probably wrong. Some individuals can thrive on ~five hours of sleep, but genetically, they’re incredibly rare (less than 1% of the population!).3 The rest of us risk cognitive and physical damage from long-term restrictions.1
4. You can’t “train” your way out of needing sleep. Your brain and body keep the receipts. Your body’s sleep regulation is deeply rooted in neurobiology. Trying to “train” yourself to need less sleep will ultimately build cumulative sleep debt, impairing your memory, your focus, and your mood.1
5. Temporary planning might help you cope, but it won’t eliminate your sleep needs. You might get away with giving up a bit of sleep to get through a big deadline or jet lag by planning your downtime around it. But know that this will only mask the effects briefly. Even short-term sleep restrictions will impact your immune function and metabolic health.4
6. Stimulants can wake you up, but they don’t make you well-rested. Tools like caffeine and alertness drugs can’t replace real sleep. While they can mask the symptoms of sleep loss, they won’t restore deep brain functions, emotional regulation, or your body’s healing processes. They can even disrupt restorative sleep stages when used excessively.1
7. It’s not just about fatigue. It’s about your life expectancy. Chronic sleep loss is linked to an increased risk of diabetes, heart disease, obesity, and even early mortality.5
8. We live in a world that treats sleep like a weakness, which comes at a great cost. The normalization of poor sleep is a public health crisis. Most adults are under-sleeping, which is silently undermining your productivity, health, and general well-being.6
9. Future sleep strategies need to go beyond traditional advice. Generic tips like “sleep in a dark room” aren’t enough anymore. Modern sleep science calls for individualized approaches like aligning your sleep with your circadian rhythms, strategic napping, and managing light exposure.7
The bottom line is that you can’t train your body to need less sleep. What you can re-train are your priorities to make space and time for it. Sleep is your life’s support system, not a luxury. If you want to thrive, you need to protect it.
Dr. Teofilo Lee-Chiong is a highly-trained sleep medicine specialist, Prof. of Medicine at the University of Colorado Denver School of Medicine and Tenured Prof. of Medicine at National Jewish Health in Denver, Colorado. Dr. Lee-Chiong is the author of several books focused on sleep medicine.