How Many Hours of Sleep Are Needed at Each Age, According to Doctors

The amount of sleep the body needs changes throughout one's lifetime. Pulmonologist Răzvan Lungu, a certified somnologist, explained to Digi24.ro what the benchmarks are for each age group and which habits contribute to better rest. According to the specialist, bedtime, exposure to screen light, and evening activities can all influence how the body prepares itself for sleep.

Sleep requirements by age

The doctor explains that sleep requirements vary significantly across a lifetime: babies and young children need 14–17 hours of sleep per day, adults need an average of 7–9 hours, and people over the age of 65 need 6–8 hours. However, these ranges are not fixed rules — they depend on the individual characteristics of each person's body.

The specialist also mentions the existence of a genetic variation known as the "Short Sleeper Gene" (or "Short Sleeper Syndrome"), which affects people who sleep an average of just six hours a night yet wake feeling fully rested, with no known health risks.

Benchmarks by age group

• Newborns (0–3 months): 14–17 hours/day
• Infants (4–11 months): 12–15 hours/day
• Toddlers (1–2 years): 11–14 hours/day
• Pre-schoolers (3–5 years): 9–11 hours/day
• School-age children (6–13 years): 9–11 hours/day
• Teenagers (14–17 years): 8–10 hours/day
• Young adults (18–25 years): 7–9 hours/day
• Adults (26–64 years): 7–9 hours/day
• People over 65: 7–8 hours/day

Is it beneficial to keep a fixed sleep schedule?

Dr Răzvan Lungu recommends maintaining a consistent routine, with similar bedtimes and wake-up times every day, regardless of whether it is a weekday or not. Ideally, bedtime should be no later than 11:00 pm, and wake-up time can vary between 7:00 and 9:00 in the morning, depending on one's schedule.

According to the specialist, the body has an "internal clock" influenced by two factors: genetic predisposition — assessed by the doctor using specific questionnaires — and social conditioning, shaped by one's daily routine (nursery, school, work). This internal clock can adapt to changes such as the shift to summer or winter time, or a change in time zone.

How to improve sleep quality

The doctor recommends avoiding, as much as possible, exposure to screen light (mobile phone, tablet, TV) before bedtime, as blue light can reduce the secretion of melatonin, the hormone required for sleep. In the one to two hours before bed, warm, ambient lighting is preferable to bright light.

The body also needs a transition period before sleep in order to unwind from the stress and bustle of the day. Reading a book or listening to a podcast or some relaxing music at low volume can be helpful in this regard.

"People should be aware that we must not sacrifice sleep in order to complete other tasks, because the body has certain biological limits. We need a minimum amount of sleep, and if we do not get it, we will feel fatigued and certain medical conditions may develop," concluded Dr Răzvan Lungu.