Being tired is the worst thing you can do to your face. Or yourself. You get comments about it and unsolicited advice on how you should get more rest. But before you get upset at others, you've got to find out why you're tired in the first place. Here are some 24 reasons.

1. You're dehydrated

Being dehydrated takes a toll on energy levels. It can cause blood to thicken which makes your heart pump oxygen and nutrients that you need much slower than usual.

The fix: Drink more water.

2. You may not be consuming enough iron

Iron is vital in the delivery of oxygen. A lack of it can make you feel sluggish, irritable and weak.

The fix: Eat lean beef, kidney beans, tofu, eggs, dark green leafy vegetables, nuts and peanut butter. If you have an iron deficiency, it's best to see a doctor.

3. Junk food can have a serious impact on sleep

Eating junk food can increase blood sugar quickly, and when it spikes, you might feel fatigue over the course of a day.

The fix: Avoid junk food before sleep. Eat lean protein and whole grains.

4. If you skip exercise, you'll get even more fatigued.

It seems counterintuitive, but adults who exercise for less than 20 minutes three times a week were less fatigues compared to those who didn't at all. Regular exercise helps keep your heart healthy, and better at delivering oxygen.

The fix: Make the time to exercise. It is essential!

5. Your room is too bright

Lights in our room can enter your retina even when your eyes are closed. When we see light, our brain thinks it is time to wake up.

The fix: Turn off all electronics, and sleep in total darkness. You'll sleep better, we promise!

6. You could be exercising too much

If no exercise is bad, too much of it is just the same. Cortisol is released during heavy exercise, and it suggests that sports can sometimes by physically stressful. If you push your body beyond its limits, it can lead to trouble sleeping and exhaustion.

The fix: Follow an exercise plan.

7. Don't let the dog into bed

Dog and cat owners admit to losing sleep because they share their bed with their pets.

The fix : Make the bed off limits. Humans only!

8. You could be low on B12

Vitamin B12 is naturally found in animal foods. Your body needs it to make red blood cells. A low count means less oxygen for blood to carry through your body.

The fix: Take B12 supplements.

9. If you strive for perfection, you're going to be knackered

People who set unrealistic goals can be stressed out when they think of a sense of failure. In other words, you could be mentally draining yourself.

The fix: Don't take on too many projects you can't handle.

10. Your hormones might be fluctuating

Women on their period and throughout perimenopause have fluctuating levels of estrogen and progesterone, which could rob you off some sleep.

The fix: Take a quick bath before turning in and maintain a consistent sleep schedule.

11. If your room is a mess, so is your mind

Having clutter all around you might mentally exhaust you. You might not be able to focus, according to a Princeton study. It can also affect your sleep.

The fix: Tidy up your room and desk.

12. Make sure you're not going to bed hungry

If you go to bed hungry, it might disrupt your sleep. People who are on a diet usually have a hard time sleeping than those who aren't.

The fix: Have a high-protein snack before bed. Or just drink lots of water.

13. Be sure not to drink too late

Alcohol might be able to knock you out, but too much will abrupt your sleep. It can create a surge in the adrenaline system.

The fix: Try to avoid drinking three to four hours before bed.

14. Don't use your phone in bed

Remove all technology from your bedroom. A glaring screen from a smartphone or tablet can suppress melatonin - the hormone which regulates sleep and wake cycles.

The fix: ban all electronics from your room.

15. Your thyroids could be underactive

Your thyroid produces hormones which control sleep and hunger.You might have an underactive thyroid if you always feel sluggish even though you get a lot of sleep.

The fix: A simple blood test can detect hypothyroidism

16. A lack of magnesium could make you lethargic

Magnesium maintains blood glucose levels, muscle health and concentration so needless to say, a lack of it will make you feel lethargic.

The fix: Magnesium is found in leafy vegetables and nuts.

17. Take shorter naps

Take shorter naps to rejuvenate your strength. Try to avoid long naps.

The fix: Take cat naps no longer than 30 minutes.

18. Anxiety will cause you to lose sleep

Anxiety can lead to exhaustion and is mentally draining.

The fix: Meditate, exercise and share your concerns with someone who might listen to help you cope with whatever you're worrying about.

19. Eat breakfast

Sleeping takes up a lot of energy, so it is best to refuel when you get up.

The fix: Have a breakfast that includes lean protein, whole grains and healthy fat.

20. Don't stay up too late on weekends

Although hard to do, late nights can throw off your internal clock.

The fix: Try to be in bed no longer than an hour longer than usual on weekends. You can't really make up for loss sleep, and sleeping in longer will only make you more tired.

21. You might have a food intolerance

If you get tired after eating a certain food, you might have a food intolerance. It is best to go check with a doctor.

The fix: Avoid eating any foods that seem to make you tired, or visit a doctor.

22. You could be dependent on caffeine

Caffeine blocks adenosine - which is a byproduct of active cells that drives you to sleep as it accumulates. Consuming caffeine six hours prior to bed interfered with sleep.

The fix: Cut off coffee by the mid-afternoon.

23. Learn to say no

People pleasers spend a lot more energy trying to make others happy. It also comes at the expense of your own happiness, leaving you resentful and angry over time.

The fix: Start small by making excuses you can't do something, and then graduate to just saying no.

24. Be sure take time off

If it is time to relax, then relax. If you are at the risk of exhaustion, it is best to unplug and unwind. Go for a holiday perhaps!

The fix: Take a holiday, or just relax from the stress of the world at home by doing something fun and mindless.