What’s the difference between feeling tired and having fatigue?

If you’re like most Americans right now, you’re wandering through life a sleep-deprived zombie, reaching out for your iced coffee like it’s the life raft that will pull you out of the foggy depths of your….sorry, where was I? I didn’t sleep very well last night, and I’m having a hard time focusing.

Oh, right: fatigue! In today’s fast-paced world, it’s normal to feel tired all the time (or as we like to call it, TATT). The Centers for Disease Control and Prevention (CDC) reports that one-third of adults don’t get enough sleep at night. A 2019 study published in the journal Sleep found that the number of Americans getting fewer than six hours of sleep per night has increased by 4 percent since 2013. If you’re thinking that doesn’t sound that bad, consider that lead study author Connor Sheehan told ASU Now that it’s equivalent to “the population of New York, or two Phoenixes, who are sleeping worse over four years.”

In other words, if you’re yawning while reading this, you’re in good company. However, there’s a big difference between being tired and something more serious. It’s totally normal to feel a little tired after a couple of late nights out with your girls or even after a few stressful work weeks. But fatigue…that’s a bit different.

Somewhat paradoxically with fatigue, you don’t necessarily feel sleepy or drowsy. Instead, it’s defined as an “overwhelming sense of feeling tired, not like yourself, or feeling really worn down,” says Sophia Tolliver, MD, a family medicine physician at The Ohio State University Wexner Medical Center.

The key difference between the two is that feeling tired and sleepy should be temporary, and once you get back to your normal sleep habits, you’ll be feeling better. Constant, unrelenting fatigue is “not normal,” Dr. Tolliver says, and could be a sign that you need to hit reset on your habits or talk to your doc.

If you’re feeling more tired than usual, Dr. Tolliver suggests taking a step back and looking at your daily life from all angles. Has something in your life recently changed? Has it been weeks since you hit the gym? Have you experienced any recent stressors? You may also want to check your medicine cabinet—Dr. Tolliver says that some medications, including certain antibiotics and antidepressants, can also cause fatigue.

“Anemia is also a huge one,” she says. “Your red blood cells are responsible for your oxygen-carrying capacity, so if they’re malfunctioning, that can definitely translate into that feeling of tiredness.”

So how to deal? “One of the best ways to improve fatigue, no matter what the cause, is by increasing your physical activity,” Dr. Tolliver says. She also recommends cutting back on junk food, adding in more whole foods, and taking a short daily nap (20 to 30 minutes). It’s also a good idea to look up from the blue light on your screen once in a while, especially before bed—so, no more scrolling mindlessly through Twitter at 10 p.m.

But if you’ve been working out diligently, filling your plate with healthy proteins and veggies, and doing a digital detox for weeks, and you’re still experiencing the kind of bone-deep fatigue you just can’t shake, it’s time to make an appointment with your doctor. Dr. Tolliver says you could have a more serious underlying condition, especially if you also find yourself feeling foggy, unable to concentrate, anxious, depressed, or lacking the energy or motivation to do the things you normally love. Your doctor can help you come up with a treatment plan that’s right for you.

Soon enough, you’ll be feeling more like you…and less like Sleepy from Snow White.

Other tips on improving your sleep life: taking magnesium, and sleeping with a “sleep robot.”