16 Reasons Why Your Energy Is Low or Depleted

By Deborah Mitchell
Deborah Mitchell
Deborah Mitchell
August 12, 2019 Updated: August 12, 2019

Experiencing low or depleted energy occasionally is normal, but you don’t want to go through life feeling like you can’t get out of first gear, do you?

According to experts, one out of 10 people around the world are experiencing persistent tiredness at any one time, and one in every 5 Americans say they have fatigue that interferes with their daily lives.

When low energy becomes chronic, it’s time to uncover the cause and find ways to remedy the situation. The first step, however, is identifying the reason. To help you, we’ve come up with 16 reasons why people can experience low or depleted energy. Could your answer be on this list? If you believe it is—or even if it’s not—it may be time to ask a health care provider to help you ferret out the final answer, get tested, and begin the treatment you need.

16 Reasons Why You Have Low Energy

1. Adrenal Fatigue

Adrenal fatigue is a syndrome that occurs when the adrenal glands, which sit on top of the kidneys, are unable to produce enough hormones (e.g., cortisol, aldosterone, adrenaline) to maintain homeostasis. This typically occurs because of chronic  or a single extremely stressful situation. Indications that you may have adrenal fatigue include:

  • Feeling tired for no reason, even though you get a sufficient amount of 
  • Difficulty getting up in the morning, despite going to bed at a reasonable time
  • Feeling overwhelmed or rundown
  • Craving sweets and salty foods
  • Feeling more awake and energetic after 6 p.m. than you do doing the day
  • Trouble recovering from stress or illness

2. B12 Deficiency

Vitamin B12 is essential for the formation of red blood cells, optimal functioning of nerve tissue, and absorption of folic acid, among other things. A deficiency of vitamin B12 typically develops gradually over years, and initial symptoms may be subtle. It’s estimated that about 6 percent of people aged 60 and older are deficient in vitamin B12 in the United States and the United Kingdom, and nearly 20 percent have marginal levels.

When someone doesn’t get enough B12, production of red blood cells declines and, if not treated, will eventually result in anemia once the red blood cell count drops too low. Vitamin B12 deficiency may also result in pernicious anemia, a blood disorder in which individuals can’t make enough intrinsic factor (IF) in the stomach. Without enough IF, individuals can’t absorb B12, which means they require B12 injections that bypass the stomach.

Possible causes of B12 deficiency include Crohn’s disease, short bowel syndrome, atrophic gastritis,  surgery, intestinal parasites, lupus, Graves’ disease, pernicious anemia, following a vegan diet, and chronic alcoholism. Risk of deficiency also increases with age.

The most common symptoms of B12 deficiency anemia are:

  • Tiredness
  • Shortness of breath
  • Palpitations (irregular and/or heavy beating of the heart)
  • Sore tongue or mouth
  • Weight loss
  • Yellowish or pale skin
  • Menstrual difficulties

A simple blood test can identify the presence of vitamin B12 deficiency.

3. Candida

Candida is a fungus (type of yeast) that exists in low levels in the mouth and intestinal tract, where it helps with absorption of nutrients and digestion. When this fungus is overproduced, however, it can cause an infection in the vagina, mouth, and intestinal tract, although it may also affect the skin and mucous membranes. Among people who have a weakened immune system, the infection can spread to the blood and membranes around the brain and heart.

Factors that can cause candida infection include eating a diet high in processed carbohydrates and sugar, chronic stress, use of antibiotics, use of oral contraceptives, a weakened immune system, and diabetes. Signs and symptoms of a candida infection include:

  • Exhaustion (regardless of how much sleep you get)
  • Cravings for sweets
  • Vaginal or urinary tract infection (recurring)
  • Gas and bloating
  • Thrush or white coating on the tongue
  • Bad breath
  • Joint pain
  • Mental fogginess
  • Loss of libido
  • Chronic allergy, sinus, nasal drip problems
  • Mood swings

If you suspect you have a candida infection, a comprehensive stool test should provide the answer so you can begin treatment, including dietary changes.

4. Depression

Most of us feel sad or lonely occasionally, but when such feelings become overwhelming, cause physical problems, significantly impact everyday activities, and last for months, then you’re likely dealing with clinical or major depression. It can reduce your energy levels and disrupt your sleep, making you even more tired during the day.

  • Fatigue and reduced energy
  • Trouble with memory, concentration, making decisions
  • Feelings of worthlessness, guilt, or helplessness
  • Irritability, restlessness
  • Insomnia, excessive sleeping
  • Loss of interest in activities or hobbies once pleasurable, including sex
  • Loss of appetite or overeating
  • Feelings of hopelessness or pessimism
  • Persistent physical symptoms such as headache, cramps, pains that are not relieved with treatment
  • Persistent feelings of sadness, anxiety, or being “empty”
  • Thoughts of suicide or suicide attempts

If you are experiencing symptoms of depression, you can seek help from a mental health professional.

5. Fibromyalgia

Although the first symptom you may think of when you think about fibromyalgia is chronic pain, chronic fatigue also is a significant part of this syndrome. Approximately 10 million people in the United States have fibromyalgia, and the condition affects 3 to 6 percent of the world’s population. The majority of those affected (75 to 90 percent) are women. It can occur alone or with other conditions, such as rheumatoid arthritis or lupus.

The cause of fibromyalgia is unknown, although experts have noted that the central nervous system appears to be hypersensitive in people with this disease. Diagnosis is a challenge because there are no definitive tests and the signs and symptoms mimic those of numerous other conditions. The symptoms also vary considerably from person to person. That said, here are typical signs and symptoms of fibromyalgia:

  • Fatigue
  • Chronic pain, stiffness, or tenderness of muscles, joints, and tendons
  • Restless sleep
  • Anxiety, mood changes
  • Depression
  • Problems with memory, concentration, attention
  • Abdominal pain related to irritable bowel
  • Irritable bladder
  • Headache, migraine
  • Tingling and numbness

6. Food Hypersensitivities (Gluten)

People who have food hypersensitivities or food intolerance have difficulty digesting certain foods. Food hypersensitivity differs from a food allergy, which triggers the immune system and histamine response, while food hypersensitivity doesn’t. However, it can cause a variety of symptoms, including:

  • Bloating
  • Headaches, migraines
  • Cough
  • Runny nose
  • Tiredness
  • Irritable bowel
  • Stomach pain
  • Hives

Foods most often associated with food intolerance include grains that contain gluten (e.g., wheat, rye, barley), dairy products, and items that can cause intestinal gas accumulation such as cabbage and beans. Individuals with a food hypersensitivity usually aren’t bothered by eating tiny amounts of the offending foods, while those who have a food allergy typically respond immediately to even tiny amounts.

7. Insufficient Sleep

It’s no surprise that getting insufficient sleep leads to tiredness, but the challenge can be in identifying and treating the cause. Possible candidates include:

  • Chronic pain
  • Too much light, including the white/blue light from electronic devices
  • Getting up frequently to urinate (possible urinary tract infection)
  • Insomnia
  • Sleep apnea, which could be undetected or undiagnosed
  • Snoring partner
  • Uncomfortable sleep environment (i.e., uncomfortable mattress, temperature, pillow, noise)

Any exploration into why you are tired should begin with some reflection on whether the cause (or contribution) is related to factors that are limiting your sleep, such as those listed above. Naturally, feeling tired or fatigued can be caused by more than one situation or circumstance.

8. Iron Deficiency

Similar to vitamin B12 deficiency, iron deficiency involves red blood cells. In this case, however, there’s an insufficient amount of iron to produce hemoglobin, which is the part of the red blood cells that allows the cells to carry oxygenated blood throughout the body.

Iron deficiency anemia is estimated to occur in 2 percent of adult men, 9 to 12 percent of non-Hispanic white women, and nearly 20 percent of black and Mexican American women. It is the most common nutritional deficiency in the world and can be caused by blood loss (often through menstruation), insufficient iron in the diet, poor absorption, and pregnancy. Symptoms of iron deficiency anemia include the following:

  • Extreme fatigue
  • Shortness of breath
  • Chest pain
  • Pale skin
  • Weakness
  • Headache
  • Dizziness
  • Cold hands and feet
  • Frequent infections
  • Inflamed or sore tongue
  • Fast heartbeat
  • Poor appetite
  • Brittle nails
  • Unusual tingling or crawling feeling in your legs

A blood test can detect an iron deficiency.

9. Lack of Exercise

The adage “energy begets energy” is true; if you are inactive, you are “feeding” your own tiredness or fatigue. That is, a sedentary lifestyle or lack of exercise can lead to fatigue.

Such lack of physical activity may be the result of an injury, chronic health condition, boredom, or lack of motivation.

10. Low Thyroid

The thyroid gland, which is located in your neck, produces a hormone that helps regulate your energy usage. When the gland fails to produce enough of the hormone, your thyroid is said to be underactive. Also known as hypothyroidism, this condition is characterized by low energy and fatigue, as well as a few other symptoms.

Symptoms of hypothyroidism include

  • Fatigue
  • Increased sensitivity to cold
  • Constipation
  • Dry skin
  • Weight gain
  • Puffy face
  • Hoarseness
  • Muscle weakness
  • Elevated blood cholesterol level
  • Muscle aches, tenderness, and stiffness
  • Pain, stiffness, or swelling in your joints
  • Heavier than normal or irregular menstrual periods
  • Thinning hair
  • Slowed heart rate
  • Depression
  • Impaired memory

You can have a blood test to determine if your thyroid hormone levels are the cause of your tiredness.


If you are going through menopause, feeling tired some or much of the time is likely nothing new. In fact, up to 61 percent of postmenopausal women experience symptoms of insomnia, and as many as 92 percent say they are generally tired.

Tiredness during menopause is associated with hormonal changes that play havoc with your entire body and cause symptoms that impact sleep, such as hot flashes, night sweats, pain, anxiety, and depression. Typical symptoms of menopause and fatigue include:

  • General lack of energy
  • Sleepiness during the day
  • Desire for naps
  • Difficulty focusing on your regular routine
  • Mood changes and irritability

Talk to a qualified healthcare professional about natural ways to deal with menopausal symptoms, including tiredness and fatigue.

12. Postpartum

One of the most common complaints of new moms is feeling exhausted. Along with going through the ordeal of childbirth (and recovering from a C-section, if that’s the case), new moms have a whole new set of infant-related activities to keep them occupied around the clock, cutting into much-needed sleep time.

Postpartum tiredness can last a few weeks to months, depending on how well a baby sleeps, how much in-home support women have, how well women can adjust their schedule, and demands of an outside job, among other factors.

Tiredness that lasts for months and is accompanied by feelings of despair and a loss of interest in just about everything in your life could be postpartum depression. If this is the case, ask your doctor for a referral to a therapist. It’s also possible your postpartum fatigue is related to anemia or an underactive thyroid gland (hypothyroidism). If your fatigue seems to be getting progressively worse, call your doctor to see if you should be tested for these or other conditions.

13. Seasonal Depression

Seasonal affective disorder (SAD), also known as seasonal depression, is a type of depression that is related to changes in the seasons. Most people who experience SAD have symptoms that begin in the autumn and last throughout the winter months. Fewer people develop SAD during the spring and summer months.

Symptoms specifically associated with autumn and winter SAD include:

  • Low energy or tiredness
  • Irritability
  • Hypersensitivity to being rejected
  • Excessive sleeping
  • Difficulty getting along with other people
  • Heaviness in the arms or legs
  • Cravings for carb-rich foods (“comfort foods”)
  • Weight gain

If you experience symptoms of SAD, there are several natural ways, including nutrition and exercise, you can use to manage them. Symptoms that grow progressively worse should be discussed with a health professional.

14. Stress

Stress can take an enormous toll on your health, leaving you feeling physically exhausted and mentally drained. Left unchecked, stress can lead to heart disease, obesity, diabetes, and high blood pressure.

There’s a difference between feeling physically tired at the end of the day because you worked out at the gym or you have a physically demanding job, and feeling exhausted because of mental stress. Mental exhaustion from stress can be caused by worrying about situations in your life, such as financial worries, relationship problems, or job issues. Chronic stress becomes a way of life, and so does being tired all the time, even when you get an adequate amount of sleep and rest.

People who suffer from stress-related fatigue usually also experience other symptoms:

  • Muscle ache or weakness
  • Headache
  • Blurry vision
  • Dizziness
  • Short-term memory problems
  • Trouble with concentration or making decisions
  • Loss of appetite
  • Feeling helpless or hopeless
  • Lack of motivation
  • Slowed reflexes
  • Irritability or moodiness

15. Sugar Hangover

Hangovers don’t just occur after drinking alcohol; they can result from consuming too much sugar. The thing is the definition of “too much” sugar varies from person to person, so what causes sugar hangover symptoms in one person may not do the same in another.

Sugar consumption affects many organs in your body, from your brain to your small intestines. Sugar also feeds candida, suppresses your immune function, raises blood triglyceride levels, disrupts your digestive process, and more.

Generally, you are likely experiencing a sugar hangover if you experience the following symptoms after eating foods with sugar, including those with natural sugars:

  • Fatigue or feeling sleepy
  • Foggy thinking
  • Bloating or gas
  • Constipation or diarrhea
  • Joint pain
  • Headache
  • Allergy symptoms
  • Mood swings
  • Skin problems

16. Underlying Disease

Numerous underlying diseases or conditions are associated with tiredness or fatigue. If you don’t believe any of the aforementioned conditions are the reason for feeling so tired or exhausted, then you may have an underlying condition. Some of those conditions include but are not limited to asthma, cancer, chronic fatigue syndrome, chronic obstructive pulmonary disease, Cushing’s disease, diabetes, flu, heart disease, hepatitis, HIV, kidney disease, liver disease, lupus, mononucleosis, pneumonia, rheumatoid arthritis, and urinary tract infection. Lingering tiredness or fatigue should be checked by a health care professional.

Deborah Mitchell is a freelance health writer who is passionate about animals and the environment. She has authored and co-authored more than 50 books and thousands of articles on a wide range of topics. This article was first published on NaturallySavvy.com.

Deborah Mitchell
Deborah Mitchell