The most common reason for being tired in the morning and not at night is sleep inertia which is a normal part of the waking process.
Your brain will not usually wake up instantly after sleeping as it transitions gradually to a wakeful state and during this transition period you can feel groggy or disoriented.
And apart from sleep disorders, other factors can cause excessive tiredness during the day.
Jet lag, a circadian rhythm condition that affects overseas travelers adjusting to their current time zone, can make people very tired during the day.
Sedative medications are also known to cause daytime tiredness.
You could be sleeping so much all of a sudden due to health issues such as thyroid problems or other hormone changes.
Or you could have sleep disorders, sleep apnea, sleep deprivation or depression and other psychiatric problems.
Even certain medications and medical conditions that affect your brain and body can cause daytime drowsiness.
Other health issues that can cause you to sleep a lot include.
Heart disease, diabetes, hypothyroidism and Anemia.
Old people tend to sleep so much due to health problems such as sleep apnea, cognitive impairment, or cardiovascular issues.
Sleep Apnea: Obstructive sleep apnea can cause pauses in breathing during sleep.
And as people age, they tend to sleep more lightly than when they were younger.
Waking up during the night due to achy joints or the need to use the restroom becomes commonplace.
Many older people and seniors compensate for this lost sleep by catching a restorative nap during the day. That's normal.
An adult needs between 7 to 8 hours of sleep per night for optimal health and to function properly.
Getting less than 7 hours of sleep per night can cause health problems and make you prone to accidents during the day and cause you to lose focus.
Doctors and health professionals that healthy adults need between 7 and 9 hours of sleep per night.
Babies, young children, and teens need even more sleep to enable their growth and development.
People over 65 should also get 7 to 8 hours per night.
How Much Sleep Is Too Much?
Sleep needs can vary from person to person, but in general, experts recommend that healthy adults get an average of 7 to 9 hours per night of shuteye.
If you regularly need more than 8 or 9 hours of sleep per night to feel rested, it might be a sign of an underlying problem.
Sometimes life calls and we don't get enough sleep.
But five hours of sleep out of a 24-hour day isn't enough, especially in the long term.
According to a 2018 study of more than 10,000 people, the body's ability to function declines if sleep isn't in the seven- to eight-hour range.
While sleep requirements vary slightly from person to person, most healthy adults need seven to nine hours of sleep per night to function at their best.
Children and teens need even more.
And despite the notion that our sleep needs decrease with age, most older people still need at least seven hours of sleep.