Have you been yawning a lot lately? Are you feeling like you could sleep all day? There are many reasons why you might be tired. You may not be getting enough shut-eye because you’re staying up too late, but you could also be tired because you have an undiagnosed medical condition.

Experts at the have laid out the following guidelines:

AgeAmount of sleep
Newborns14–17 hours (includes naps)
Infants12–15 hours (includes naps)
Toddlers11–14 hours (includes naps)
Preschool-aged children10–13 hours
School-aged children9–11 hours
Teens8–10 hours
Adults7–9 hours
Seniors7–8 hours

There is a range in these numbers because sleep requirements are unique to each individual. The amount of sleep you need to function your best could be less or more than anyone else. Your sleep needs can also be affected by health and lifestyle factors such as pregnancy, illness, aging, sleep deprivation, or sleep quality.

Too much or too little sleep can lead to different issues, including:

  • trouble with alertness
  • difficulty with memory
  • stress with relationships
  • lower quality of life
  • increased chance of car accidents

Some medical conditions can lead to fatigue. If your exhaustion continues beyond just a few days or weeks, you should head to your doctor for a checkup.

1. Iron deficiency

Iron deficiency, also called anemia, is a condition that can make you feel extremely run-down and exhausted. That’s because iron is what produces red blood cells, and without enough red blood cells your blood can’t supply your organs with the amount of oxygen they need to function properly. Other symptoms of this condition include shortness of breath, heart palpitations, and pallor.

Iron deficiency is common in women who still menstruate and about men and postmenopausal women.

2. Sleep apnea

Sleep apnea is a condition where your throat may narrow or even close for or more as you sleep. This can make it difficult for you to breathe, causing you to wake often at night as your body reacts to the stopped airflow.

Waking often at night can make you feel tired throughout the daytime hours. Sleep apnea may also cause you to snore and have a drop in your blood oxygen levels. This condition is more common in overweight, middle-aged men.

3. Depression

Tiredness is a common symptom of depression. Depression can leave you feeling drained of all your energy, and it may even make it difficult for you to fall asleep or cause you to wake up early each day. Other symptoms of this mood disorder, which include feelings of hopelessness, anxiety, low sex drive, and aches and pains, can range from mild to severe.

4. Pregnancy

Fatigue is one of the earliest symptoms you might experience during pregnancy. In the first trimester, your body produces a lot of progesterone, a hormone that can make you tired.

Other early symptoms of pregnancy include a missed period, sore breasts, nausea, and increased urination. If you think you may be pregnant, you can visit your doctor or take an over-the-counter pregnancy test for confirmation.

5. Diabetes

Being overly tired is one of the main symptoms of diabetes. You may also feel excessively thirsty, use the bathroom more frequently, or lose weight. Since diabetes is caused by too much sugar in your blood, a blood test may be able to help your doctor with a diagnosis.

6. Underactive thyroid

A common symptom of hypothyroidism is feeling tired. The symptoms of this condition develop slowly, so you might not notice any right away. You can also experience weight gain, depression, or muscle aches and pains.

A blood test can help your doctor measure your hormone levels for a proper diagnosis. Underactive thyroid is more common in women and older adults.

7. Chronic fatigue syndrome

Have you been extremely tired for more than six months? You may have chronic fatigue syndrome (CFS). Even if you’re getting good rest, you will still feel tired if you have this condition.

Other symptoms you may experience include sore throat, headache, or muscle or joint pain. CFS most commonly affects people in their . It can also affect children between ages 13 and 15.

8. Narcolepsy vs. being tired

Narcolepsy, a condition that causes people to fall asleep suddenly, usually develops in people between the ages of .

Symptoms of narcolepsy include:

  • Sudden loss of muscle tone that can lead to slurred speech or general weakness. Also called cataplexy, this symptom may last only a few seconds to several minutes. It is usually triggered by intense emotions.
  • Sleep paralysis, which is an inability to move or speak as you fall asleep or wake up from sleep. These episodes usually only last a few seconds or minutes, but they can be extremely frightening.
  • Hallucinating as you wake between dreams and experiencing your dreams as reality.

9. Sleep debt

Humans cannot live without sleep. For many people, sleep debt is to blame for feeling chronically tired throughout the day. Sleep debt happens when you don’t get enough sleep for days, weeks, or months on end. It can have negative impacts on your health, like elevating cortisol levels or creating insulin resistance.

You can’t “make up” sleep, but making lifestyle changes can help tremendously with getting your body and mind back on track and feeling rested again. Think of it as repaying your sleep debt. Try sleeping in a few extra hours on the weekend or going to bed a few hours earlier at night.

Make an appointment with your doctor if lifestyle changes and better sleep habits aren’t helping you. You should also talk to your doctor if your sleepiness is accompanied by the symptoms of the conditions listed above or if you have other concerns about your health.

Your doctor can perform tests depending on what they think might be causing your exhaustion. It may be helpful for you to keep a sleep diary to give your doctor a full picture of your nighttime habits. Be sure to include when you fall asleep and wake up, how often you wake at night, and any other symptoms you feel are worth noting.

Follow these tips to get a better night’s sleep:

Try sticking to a sleep schedule. Follow it during the week and on weekends to keep your rest times consistent.

Create a bedtime ritual. Dim the lights and engage in quiet, relaxing activities.

Avoid napping, as it can interfere with nighttime sleep. Naps in the late afternoon may particularly make it difficult to fall asleep at night.

Exercise each day. Vigorous exercise may help you sleep best, but even a light workout can help you nod off more easily at night.

Fine-tune your sleep environment. Most people sleep best when the room temperature is between . If there are distractions in your environment, consider using blackout curtains, earplugs, or a white noise machine.

Check your pillows and mattress. If they aren’t comfortable, it may be difficult for you to fall asleep. A mattress should last you around . While you’re at it, make sure these items are free from allergens that might bother you.

Q:

What’s the difference between being fatigued and being tired?

A:

There is no difference. “Fatigued” is just the term we use in the medical field for being tired. As above, there are lots of different reasons for why you may be tired: chronic illnesses, depression, medications. Usually you will have other symptoms at the same time that will point to what the underlying problem is.

Suzanne Falck, MDAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.