GirlsGuideTo | 5 Things That Make You Tired

Struggling to wake up this morning? Drinking yet another cup of coffee to fight off the 3pm sleepies? While we all are tired now and then, if you feel your fatigue is chronic, here are five energy suckers and what you can do about it.

1. Dehydration
It turns out that even moderate dehydration (which results in the loss of 3 percent of your body weight) can make you feel mentally sluggish and mess with your concentration. The next time you're feeling foggy or lightheaded, don't just assume you're in serious need of some food. Try downing a glass or two of water.

2. Cell Phones
Checking your cell before bed revs up brain activity, making it harder to doze off. Plus, any electronic gadget's artificial blue light can suppress the sleep hormone melatonin. A 2011 poll by the National Sleep Foundation found that 20 percent of people ages 19 to 29 are awakened by a call, text, or e-mail at least a few nights a week. Power it down well before bedtime.

3. Medication
Many drugs have veiled energy-sapping side effects. Chief among them are some classes of antidepressants and certain beta-blockers used to prevent migraines or treat high blood pressure. If you start a new med and feel more lethargic than usual, see your doctor for an alternative. (If there isn't one, take your dose right before bed.)

4. Overtraining
While working out zaps the stress hormone cortisol, prolonged sweat sessions—like, for example, regularly running for more than 30 minutes at a steady rate—can actually increase cortisol production...and wear you out. Interval training (bursts of intense activity) combined with strength training (free-weight and body-weight moves) helps keep cortisol in check.

5. Low Iron
The mineral shuttles oxygen around your body and removes waste from your cells. If you're not getting around 18 milligrams a day, your body struggles to function properly and you can feel worn out; low iron levels in your diet can cause iron deficiency anemia. And your monthly cycle doesn’t help…If you feel sluggish, eat more leafy greens or grab a burger. If that doesn’t help, ask your doctor for a simple blood test to see if you should be taking a supplement.