The National Sleep Foundation recommends 7-9 hours sleep per night for young adults. These figures don’t, however, take into account inter-individual variability and are age-dependant.
Sleep needs vary a lot from one person to the next. As is often the case, our genes hold the answer, it’s our genes that determine whether we’re a short sleeper or a long sleeper. What’s more sleep changes as we age.
Although it’s not 100% sure that the amount of sleep we need varies during adulthood, the way we sleep differs significantly. Older people often report experiencing poor quality sleep, it’s shallower than before with regular awakenings during the night. Yet their sleep is usually more distributed throughout the day and retirees tend to nap more during the day.
As you can see below, older adults have a much more fragmented sleep and the deep sleep ratio decreases.