You go to bed tired. You wake up tired. You push through the day with coffee, energy drinks, or sheer determination—and by the afternoon, you are ready for a nap.
Sound familiar?
Everyone feels tired occasionally, especially after a stressful week or a few nights of poor sleep. But if you are tired all the time, your body may be trying to tell you something.
Persistent fatigue can have many causes. Sometimes it is related to lifestyle, stress, or inadequate sleep. Other times, fatigue can be a sign of a nutrient deficiency, sleep disorder, medication side effect, medical condition, or hormone imbalance.
The important thing to understand is that fatigue is a symptom—not a diagnosis. Finding the reason behind it is the first step toward feeling like yourself again.
What Does Fatigue Actually Feel Like?
Fatigue is more than simply feeling sleepy. It may feel like:
- Having very little physical or mental energy
- Struggling to get out of bed in the morning
- Feeling exhausted even after a full night of sleep
- Needing caffeine to function
- Losing motivation to exercise or complete everyday tasks
- Having trouble concentrating or remembering things
- Feeling physically weak or unusually “heavy”
- Becoming irritable, overwhelmed, or emotionally drained
- Experiencing an afternoon energy crash
- Taking much longer to recover from exercise
Because fatigue can look different from person to person, it is important to consider your other symptoms, sleep quality, medications, health history, and how long the problem has been going on.
Common Causes of Fatigue
- You Are Sleeping—but Not Sleeping Well
Getting eight hours in bed does not always mean you are receiving eight hours of restorative sleep.
Stress, pain, alcohol, nighttime bathroom trips, hot flashes, restless legs, and an inconsistent sleep schedule can repeatedly interrupt your sleep. You may not remember waking up, but your body can still miss the deeper stages of sleep it needs for recovery.
Sleep apnea is another commonly overlooked cause of fatigue. It causes breathing to repeatedly stop or become restricted during sleep. Warning signs may include:
- Loud snoring
- Gasping or choking during sleep
- Morning headaches
- Dry mouth upon waking
- Difficulty concentrating
- Irritability
- Daytime sleepiness
- Waking up tired despite spending enough time in bed
Sleep apnea can affect both men and women, and you do not have to fit a particular body type to have it.
- Stress Is Keeping Your Body in Overdrive
When you are constantly managing work, family, finances, relationships, and an endless to-do list, your body may have difficulty fully relaxing.
Chronic stress can interfere with sleep, increase muscle tension, affect appetite, and leave you mentally and physically drained. Anxiety and depression can also cause significant fatigue—even when sadness is not the most noticeable symptom.
Mental health and physical health are closely connected. Fatigue related to emotional stress is real and deserves the same attention as any other symptom.
- You May Have an Iron or Vitamin Deficiency
Your body needs adequate nutrients to produce energy and carry oxygen to your tissues. Low levels of certain nutrients may contribute to fatigue, weakness, brain fog, headaches, dizziness, or shortness of breath.
Possible deficiencies include:
- Iron
- Vitamin B12
- Folate
- Vitamin D
Iron deficiency can cause symptoms even before a person develops obvious anemia. It is especially important to consider in people with heavy menstrual periods, gastrointestinal bleeding, restricted diets, pregnancy, or difficulty absorbing nutrients.
Vitamin B12 deficiency may be more likely in people taking metformin or certain long-term acid-reducing medications, as well as those following vegan or vegetarian diets or living with digestive conditions that affect absorption.
Supplements should not automatically be started based on symptoms alone. Testing helps identify what is actually low and guides appropriate treatment.
- Your Thyroid May Be Underactive
The thyroid produces hormones that help regulate metabolism, temperature, digestion, heart rate, and energy production.
When the thyroid is underactive—a condition called hypothyroidism—symptoms may include:
- Fatigue
- Weight gain
- Feeling cold
- Constipation
- Dry skin
- Hair thinning
- Muscle aches
- Depression or low mood
- Heavy or irregular menstrual periods
- Difficulty concentrating
These symptoms overlap with many other conditions, so thyroid problems cannot be diagnosed based on fatigue alone. Blood testing is needed to evaluate thyroid function.
Can a Hormone Imbalance Cause Fatigue?
Yes, hormone changes can contribute to fatigue—but hormones are only one piece of the puzzle.
A thorough evaluation should look at the entire picture instead of assuming that every case of low energy is caused by “low hormones.”
Fatigue During Perimenopause and Menopause
During perimenopause, estrogen and progesterone levels may fluctuate significantly. These changes can contribute to:
- Hot flashes and night sweats
- Difficulty falling or staying asleep
- Mood changes
- Brain fog
- Changes in menstrual bleeding
- Reduced libido
- Poor exercise recovery
- Daytime fatigue
In many cases, the exhaustion is not caused by one hormone level alone. Hormone fluctuations may disrupt sleep, affect mood, and create a combination of symptoms that gradually drains your energy.
Perimenopause can begin years before menstrual periods stop completely. A woman may still have regular or mostly regular periods while experiencing hormone-related symptoms.
Low Testosterone and Fatigue in Men
Testosterone deficiency may be associated with fatigue, reduced libido, erectile difficulties, loss of muscle mass, changes in mood, and decreased motivation.
However, fatigue alone does not prove that testosterone is low. Similar symptoms can be caused by sleep apnea, depression, thyroid dysfunction, medication effects, excess weight, chronic illness, or inadequate recovery.
Low testosterone should be diagnosed using symptoms together with appropriately timed laboratory testing. The Endocrine Society recommends confirming suspected testosterone deficiency with repeated early-morning testosterone measurements rather than relying on a single result.
Testosterone therapy is not an energy booster for everyone. Treatment should only be considered after a proper evaluation of symptoms, laboratory results, health risks, fertility goals, and other possible causes of fatigue.
What About “Adrenal Fatigue”?
The term “adrenal fatigue” is commonly used online to describe exhaustion, cravings, trouble waking up, and feeling dependent on caffeine. However, it is not currently recognized as a medically established diagnosis.
Real adrenal gland disorders, such as adrenal insufficiency, can occur and may be serious. These conditions require appropriate medical testing. Persistent fatigue should not automatically be blamed on the adrenal glands—or treated with unproven supplements—without evaluating other possible causes.
Other Medical Causes of Fatigue
Persistent fatigue may also be related to:
- Diabetes or blood sugar problems
- Chronic infections
- Autoimmune disease
- Heart or lung conditions
- Kidney or liver disease
- Chronic pain
- Long COVID
- Pregnancy
- Medication side effects
- Alcohol or substance use
- Neurologic conditions
- Post-viral illness
- Myalgic encephalomyelitis/chronic fatigue syndrome, or ME/CFS
This does not mean that feeling tired is automatically a sign of a serious disease. It means that ongoing fatigue deserves an individualized evaluation rather than guesswork.
Could Your Medication Be Making You Tired?
Fatigue can be a side effect of many prescription and over-the-counter medications. Common examples include certain:
- Antihistamines
- Blood pressure medications
- Sleep aids
- Anxiety medications
- Antidepressants
- Muscle relaxers
- Pain medications
- Seizure medications
Do not stop a prescribed medication on your own. A healthcare provider can review your medication list, timing, dosage, and possible alternatives.
What Tests May Be Considered for Persistent Fatigue?
There is no single “fatigue test.” Laboratory testing should be selected based on your symptoms, health history, medications, and physical examination.
Depending on the situation, an evaluation may include:
- Complete blood count to look for anemia or other blood abnormalities
- Comprehensive metabolic panel to assess electrolytes, blood sugar, kidney function, and liver function
- Thyroid testing
- Iron and ferritin levels
- Vitamin B12 and folate
- Vitamin D
- Hemoglobin A1c or other blood sugar testing
- Hormone testing when symptoms and history suggest it may be appropriate
- Sleep apnea screening or a formal sleep study
More testing is not always better. The most useful approach is a focused evaluation guided by your specific symptoms and risks.
When Should You See a Healthcare Provider?
Consider scheduling an evaluation if your fatigue:
- Has lasted several weeks or continues to worsen
- Does not improve with adequate rest
- Interferes with work, exercise, relationships, or daily activities
- Is accompanied by brain fog, weakness, low libido, mood changes, or unexplained weight changes
- Occurs along with heavy menstrual bleeding
- Is associated with snoring or waking up gasping
- Began after starting or changing a medication
Seek prompt medical care for fatigue accompanied by chest pain, severe shortness of breath, fainting, confusion, new neurologic symptoms, vomiting blood, black or bloody stools, or thoughts of self-harm.
What Can You Do About Fatigue?
The solution depends on the cause. Helpful first steps may include:
- Track your symptoms. Note when the fatigue started, whether it changes throughout the day, how well you sleep, and what other symptoms occur with it.
- Prioritize consistent sleep. Try to maintain a regular bedtime and wake time, reduce evening screen exposure, and limit alcohol close to bedtime.
- Eat enough protein and nutrient-dense foods. Skipping meals or severely restricting calories can contribute to low energy and poor recovery.
- Stay hydrated. Even mild dehydration can leave you feeling sluggish or lightheaded.
- Use caffeine thoughtfully. Caffeine may temporarily cover up fatigue while making nighttime sleep more difficult.
- Move your body regularly. Appropriate physical activity can improve sleep, mood, strength, and energy. If exercise causes an unusual or prolonged worsening of symptoms, speak with a healthcare provider before trying to push through it.
- Avoid guessing with hormones or supplements. The right treatment begins with identifying the actual problem.
You Do Not Have to Accept Feeling Exhausted
Being busy can make you tired. But feeling exhausted day after day—despite trying to sleep, eat well, and take care of yourself—deserves a closer look.
At Bellus Medical in Minot, North Dakota, we take the time to look beyond the word “fatigue.” We consider your symptoms, sleep, stress, medications, medical history, nutrition, and possible hormone changes to help determine what may be contributing to your low energy.
Your fatigue may have one cause or several overlapping causes. The goal is not to blame every symptom on hormones or hand you a quick fix. It is to understand the full picture and build a plan that makes sense for you.
If you are tired of feeling tired, schedule a consultation with Bellus Medical.
Bellus Medical
Minot, North Dakota
Call: 701-420-2273
Text: 701-509-5614
Visit: bellusmedicalminot.com
This article is for general educational purposes and does not replace individualized medical advice, diagnosis, or treatment.
Frequently Asked Questions
Why am I tired even after sleeping eight hours?
Sleep duration and sleep quality are not the same. Sleep apnea, restless legs, pain, stress, alcohol, hormone-related night sweats, and repeated nighttime awakenings can prevent restorative sleep even when you spend enough time in bed.
What hormone imbalance can cause extreme fatigue?
Underactive thyroid function, menopause-related hormone changes, and clinically confirmed testosterone deficiency can contribute to fatigue. However, symptoms alone cannot identify a hormone imbalance. Other causes should also be considered.
How do I know whether my fatigue is hormonal?
Hormonal fatigue often occurs with other changes, such as menstrual changes, hot flashes, night sweats, low libido, erectile dysfunction, loss of muscle mass, unexplained weight changes, or temperature intolerance. A clinical evaluation and appropriate testing are needed to determine whether hormones are involved.
What vitamin deficiency makes you feel tired?
Iron, vitamin B12, folate, and vitamin D deficiencies may contribute to fatigue. Testing is preferable to taking multiple supplements without knowing whether a deficiency is present.
Can stress make me feel physically exhausted?
Yes. Chronic stress can interfere with sleep, increase muscle tension, affect appetite, and keep the body in a prolonged state of alertness. Anxiety and depression can also cause significant physical fatigue.
When is fatigue considered abnormal?
Fatigue becomes more concerning when it persists for several weeks, worsens, does not improve with rest, or interferes with normal daily activities.
Scholarly and Authoritative Resources
- Latimer KM, et al. “Fatigue in Adults: Evaluation and Management.” American Family Physician, 2023. PubMed
- Maisel P, et al. “Fatigue as the Chief Complaint: Epidemiology, Causes, Diagnosis, and Treatment.” Deutsches Ärzteblatt International, 2021. PubMed Central
- Stadje R, et al. “The Differential Diagnosis of Tiredness: A Systematic Review.” BMC Family Practice, 2016. PubMed
- American College of Obstetricians and Gynecologists. The Menopause Years
- Endocrine Society. Testosterone Therapy for Hypogonadism Guideline
- National Heart, Lung, and Blood Institute. Vitamin B12–Deficiency Anemia
- Endocrine Society. Adrenal Fatigue