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As a living human adult who likely has a demanding job, busy family life, and social life you’re working to keep afloat, there’s a good chance you are constantly feeling tired. Even if you’ve got a caffeine habit that helps you keep your head above water and get a somewhat decent amount of sleep, you may wonder if regularly feeling fatigued is normal.
According to Suneet Singh, M.D., an emergency medicine physician and medical director at CareHive Health in Austin, Texas, fatigue manifests as people feeling like they have lost physical energy, mental energy, or both.
“From a clinical standpoint, it is broken down into three constituent parts: decreased ability to initiate activities, decreased ability to maintain activities, and decreased ability to concentrate or maintain emotional stability during activities,” he explains. “When trying to understand why someone has physical fatigue, mental fatigue, or a general sense of tiredness, [your doctor] will use an approach that systematically evaluates underlying medical conditions, mental health conditions, or medication/substance-related conditions.”
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As Dr. Singh implies, in addition to poor quality sleep and a busy life that’s running you ragged, there are several other factors—having to do with your health or your lifestyle—that could be contributing to you feeling run down.
“When someone experiences excessive fatigue and tiredness, if there’s an underlying medical or mental health condition that is causing it, the best treatment is to work on the specific solutions to the underlying problem,” he says. “In all cases, though, there are some easily modifiable lifestyle factors that can be adjusted to help the overall situation.”
Discover 12 reasons you might be tired all the time and how to get some of your energy back:
1. You may have sleep apnea
Sleep apnea is a condition that occurs when the upper airways collapse back onto themselves at night, interrupting your breathing while you sleep. This unsurprisingly will cause you to experience fatigue and daytime sleepiness, with sleeping partners often reporting loud snoring, choking episodes, and gasping spells, Dr. Singh explains.
“Sleep apnea leads to periods of low oxygen levels which, in turn, decreases our ability to obtain a restful night’s sleep,” he says.
“Sleep apnea can be corrected with the right tools and if left untreated, it can affect heart health, blood pressure, and the ability to control weight,” adds Isabel Valdez, PA-C, a physician assistant and assistant professor of general internal medicine at Baylor College of Medicine. “It can also be a safety issue and endanger yourself or others if you’re so sleepy during the day that you fall asleep at the wheel or while operating heavy machinery.”
If you think you have sleep apnea, talk to your doctor about working on lifestyle factors that may be contributing to your condition, such as being overweight. Your doctor can also help you determine if you might benefit from using a continuous positive airway pressure (CPAP) machine. Find out how one sleep doctor manages his sleep apnea here.
2. You may have a thyroid disorder
The thyroid gland is responsible for creating hormones that regulate the body’s metabolism, in addition to controlling your heart rate, muscle function, and brain development, making it instrumental in helping your body function optimally, Dr. Singh says. Any conditions that adversely affect the body’s metabolism will, in turn, affect your physical and mental energy levels.
“An under-functioning thyroid leads to hypothyroidism, which tends to result in symptoms such as lethargy, fatigue, sleepiness, muscle weakness, and weight gain,” he explains. “An overactive thyroid leads to hyperthyroidism, which includes symptoms such as rapid heart rate, nervousness, hyperactivity, and poor sleep cycles.”
3. You may be anemic
Anemia is a medical condition that occurs when our red blood cells, which deliver oxygen throughout the body, are reduced or dysfunctional. Many people discover they’re anemic when they start to struggle with workouts and notice their performance and abilities are declining.
“There are several different categories and types of anemia, each with their own specific treatment recommendations,” Dr. Singh explains. “Regardless of the underlying cause of anemia, though, the impairment of oxygen delivery to our organs and tissues result in overall fatigue and tiredness.”
4. You may be experiencing depression
While there is no one reason that people experience depression, the effects it takes on one’s mental health tend to be multifactorial and are affected by a combination of various biological, psychological, and social factors, Dr. Singh. It can be a cause or contributor of why you feel tired all the time.
“Depression not only affects our mood, but it also affects our ability to concentrate and obtain restful sleep,” he says. “[The combination of fatigue and depression] can lead to a vicious cycle — no matter which came first, fatigue can lead to or worsen depression which, in turn, can lead to or worsen fatigue.”
5. You’re using medications or recreational substances
There are various substances, both legal and illicit, that lower the inhibitions of your central nervous system, Dr. Singh says. These include alcohol, marijuana, and prescription pain medications.
“Sometimes this is the intended effect of the substance while sometimes it can be an unwanted side effect, but in other, more extreme cases, coming down off the high of a stimulant can also cause the body to ‘crash’ and create fatigue and lethargy,” he says. “The more a person is exposed to this type of up-and-down behavior, the more likely that long-term fatigue can develop.”
6. Your diet may need some work
Just like with other medical problems such as heart disease or diabetes, your diet plays an important part in how you feel every day, Dr. Singh says. While there’s nothing wrong with the occasional fast or processed food indulgence, they do contribute to a slowdown in metabolism, and when paired with other vices like alcohol and caffeine, they can start to affect your physical and cognitive energy levels, especially with excessive consumption.
“When [you] eat is also an important lifestyle factor that contributes to our symptoms, so though [you] might not realize it, late-night snacking wreaks havoc on [your] sleep cycle,” he says.
7. You’re not getting quality sleep
Surprise, surprise; if you’re not sleeping well or enough, you’re bound to feel like you’re always tired as a result. Over time, you’ll likely find that you’re plagued with problems concentrating throughout the day as you wade through low-level daytime sleepiness. Setting a reasonable bedtime for yourself and consistently sticking to it may sound easier said than done, but it will undoubtedly pay off when it comes to your energy levels.
“Staying up late, especially when [you] don’t keep a regular bedtime, adds to circadian rhythm dysfunction,” Dr. Singh explains. ”Poor sleep habits make it less likely that [you’ll have] long periods of deep, restful sleep.”
8. You’re not getting enough exercise
It may seem counterintuitive, as when you’re tired, the last thing you want to do is get up and work out, right? But a lack of activity can contribute to low energy levels, whereas regular exercise gets the blood pumping and delivers endorphins that elevate your mood and energy levels, as well as promote healthier sleep.
“Getting 30 minutes of activity every day, especially aerobic exercise, has been shown to help combat fatigue and lethargy while also having a positive effect on our mental health,” Dr. Singh says.
Keep in mind, though, that exercising too late in the day may also keep you up, Valdez adds.
“You’re stimulating yourself and getting your endorphins and energy up when you exercise, so you may want to reconsider the timing of heavy aerobic exercise like a long run if you’re wanting to wind down close to bedtime,” she says.
9. You aren’t practicing mindfulness
If you tend to think of meditation as a little “woo woo,” you may want to give it a fair chance. Oftentimes, stress and anxiety manifest as physical symptoms such as restlessness, sleepiness, and fatigue, and meditation is one way to reduce your chances of experiencing depression, anxiety, and elevated stress levels, Dr. Singh says.
“Taking time every day to focus on [your] mental health is another lifestyle factor that [you can] control and helps fight fatigue,” he says. “Spending at least 5-10 minutes every day on just ourselves through activities such as deep breathing, focused concentration, or meditation helps to relax the body and ease our daily stresses.”
10. You’re not maintaining good hydration
According to Dr. Singh, dehydration has been shown to impair both physical performance and cognitive functioning. As such, you’re likely to feel tired and lethargic when you’re not consuming enough water.
“Adequate water consumption is also imperative to promoting cardiovascular health, and a healthy heart leads to an active, healthy lifestyle,” he says. “Work with your doctor to talk more about how much water is right for you, but in general, light, straw-colored urine typically indicates that your hydration needs are adequately being met.”
11. You’re drinking alcohol and caffeine too close to bedtime
Have you ever turned to a nightcap in an effort to fall asleep faster? While it may have this effect, it can backfire when it comes to getting quality sleep, Valdez says.
“While drinking in moderation (meaning no more than two standard drinks per day for men under 65) is safe, it’s best to limit your intake too close to bedtime,” she says.
Similarly, while some people aren’t affected by drinking caffeine close to bedtime, if you are sensitive to it, it would be wise to cut yourself off four to six hours before going to bed, she adds.
12. You’re getting too much screen time when it’s time to go to sleep
You’ve probably heard it before, but you really should ditch your phone and iPad once you get into bed—or 30 minutes before you do, if you can. Scrolling at night can interfere with your sleep cycle due to the blue light these screens emit, Valdez says. Similarly, if you’re a gamer, you may want to avoid playing them right before you want to go to sleep, as they will stimulate your brain as well, she says.
Emilia Benton is a Houston-based freelance writer and editor. In addition to Runner's World, she has contributed health, fitness and wellness content to Women's Health, SELF, Prevention, Healthline, and the Houston Chronicle, among other publications. She is also an 11-time marathoner, a USATF Level 1-certified running coach, and an avid traveler.
