Tired All the Time? 24 Causes of Consistent Fatigue
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There are so many reasons you may be feeling tired all day. Maybe you're not devoting enough time to sleep, or you can't fall asleep fast enough. Or it may be a hormonal or mental health issue. It's important to find the cause and try to treat it.
Poor quality sleep
Sometimes, that tired-all-the-time feeling is simply due to not getting enough sleep. The recommended amount of nightly sleep for adults is at least 7 hours; most people don’t need more than 8 hours of sleep in order to function at their best. A restful, dark, quiet place with a comfortable bed is ideal for sleep. Maintaining a regular schedule of going to bed and rising from bed also helps. Sleep apnea can severely affect the quality of your sleep as well as increase the risk of some diseases (like high blood pressure and cardiovascular disease) if it’s left untreated. Daytime naps longer than 30 minutes or late in the day can interfere with nightly sleep. Rotating shift work also can cause poor quality sleep as can jet lag.
When you use or lost more fluid than you take in, your body becomes dehydrated and unable to fulfill its normal functions. Insufficient amounts of body fluid can lead to fatigue. Dehydration is particularly serious in young children and older adults because of the lower fluid volume in their bodies.
Excess or lack of physical activity
Both too much or too little exercise can make you feel constantly fatigued. Too little exercise deconditions the body’s cardiovascular and musculoskeletal systems, leading to that always tired feeling. Likewise, too much intense daily exercise can also cause you to feel consistently fatigued due to possible dehydration and muscle fatigue. Avoiding exercise within 2 hours of bedtime can help you to sleep better, resulting in less fatigue.
Too much alcohol or caffeine
While drinking alcohol may help you to fall asleep at first, it actually disrupts your sleep by causing you to wake up more frequently during the night. Avoiding caffeine (found not only in drinks but in some foods and over-the-counter medications) within 4 to 6 hours of your bedtime will help you to sleep better. Adjusting your alcohol and caffeine intake may help to reduce your consistent fatigue.
Common allergies (like pollen, dust mites and mold), food allergies and medication allergies can cause congestion, sneezing and itchy eyes or an overall uncomfortable feeling that can make you feel tired during the day as well as disrupt your sleep at night.
Some prescription as well as over-the-counter drugs can cause you to feel tired or disturb your sleep (for example, keep you from falling or staying asleep at night). Some drugs used to treat asthma, chronic bronchitis and emphysema contain steroids and theophylline; both are stimulants and keep you awake. Some antidepressants cause daytime sleepiness or insomnia. A few cardiac medications can cause insomnia as well. And some arthritis medications can irritate the stomach, making it difficult to sleep well. Over-the-counter drugs, like nasal decongestants, antihistamines, aspirin and caffeine-containing pain relievers also can affect sleep and thus contribute to that feeling of constant fatigue.
BPH, otherwise known as an enlarged prostate gland, is common in older men, affecting almost 14 million men in the US. The larger-than-normal prostate makes it harder for them to fully empty their bladders, which results in a frequent need to urinate, even at night. The result—interrupted sleep and daytime fatigue.
This condition occurs when there aren’t enough healthy red blood cells—which have a high iron content-- to carry adequate oxygen throughout your body. Serious forms of iron-deficiency anemia can result in a feeling of constant fatigue.
The USDA (United States Department of Agriculture) recommends daily consumption of 0.8 grams of protein per kilogram of body weight as part of a healthy diet. Most people reach this goal, but those who are chronically ill, eat poorly or under eat can be at risk. Vegetarians and vegans who don’t consume enough plant-based proteins are also at risk. Long-term protein deficiency can cause your body to break down muscles in order to fulfill its need for protein. The result---consistent fatigue.
Nighttime burning pains in the lower chest (commonly referred to as heartburn) as well as coughing can significantly disrupt sleep at night for many people, either waking them up or making it difficult to fall asleep in the first place.
The relationship between hormonal changes and fatigue seem to be more significant for women than for men. Studies have shown that about 40% of women experience sleep difficulties at some point in their lives compared to 30% of men. Age-related hormonal changes during the course of a woman’s life (menstrual cycle, pregnancy, menopause) can negatively impact sleep. The disrupted sleep pattern leads to a feeling of being tired almost all of the time.
Whether chronic or sudden, pain can significantly disrupt sleep, leading to a feeling of constant fatigue. Arthritis, back pain, headaches, carpal tunnel syndrome and temporo-mandibular-joint disorder are some conditions that have a deleterious effect on sleep and can also make you feel as if your energy is being sapped all the time.
Asthma and other breathing disorders
More than half of victims of asthma experience “nocturnal asthma” --- changes in the airway at night that can cause sleep-disrupting breathlessness, wheezing and coughing. And some asthma medications can make it difficult to fall and stay asleep at night. Chronic obstructive lung disease (COPD), chronic bronchitis and emphysema can cause coughing and shortness of breath, making victims tired during the day and unable to have good quality sleep at night. In addition, almost 15% of people with COPD also have sleep apnea. And to compound their sleep problems, some COPD medications, such as albuterol and prednisone, can contribute to poor quality sleep.
Strange but true, both underactive (hypothyroidism) and overactive (hyperthyroidism) thyroid function can cause a feeling of extreme tiredness.
Lyme disease, HIV, and tuberculous are very common causes of constant fatigue. Treatment of the underlying infection usually leads to a lessening of fatigue.
Rheumatologic disorders, such as rheumatoid arthritis and lupus, can cause a feeling of constant fatigue in some people due to the pain caused by inflamed joints and tissues.
Chronic fatigue syndrome
This disease causes severe daytime fatigue that fails to improve with rest and last for more than 6 months. Although both cause and cure are yet unknown, some lifestyle changes (maintaining good sleep habits, balanced diets, regular exercise) can help some people.
Widespread muscle and soft tissue pain are the hallmarks of fibromyalgia, accompanied by persistent fatigue. Pain can be mild or severe and can take different forms—aches, stiffness, soreness or burning or gnawing pain. The cause remains unknown, as does the cure. Lifestyle changes (exercise, relaxation techniques, massage, heat treatments) in addition to anti-inflammatory medications and those approved for treating fibromyalgia (duloxetine, pregabalin and milnacipran) provide relief for some people.
Anxiety, depression and stress
Insomnia can often be caused by anxiety and can range from mild to severe. The bouts of insomnia arise whenever the feelings of anxiety arise, resulting in lasting fatigue. Insomnia is also often associated with depression, as well as the inability to fall asleep and stay asleep easily. It can also cause feelings of deep fatigue and sleepiness during the day. Stress, whatever its source (work, school, family difficulties, illness, death) is one of the most common causes of fatigue due to sleep difficulties. Once the initiator of the stress is removed, improved sleep usually occurs, resulting in a lessening or resolution of the overwhelming fatigue.
People with diabetes are unable to maintain healthy blood glucose (sometimes referred to as blood sugar) levels because of their inability to respond to or produce insulin. The result is that they cannot properly process food as energy for the body. When blood glucose levels are high, too much remains in the bloodstream rather than being used for energy. When they’re low, there’s not enough for energy to be produced. Either too high or too low, the result is fatigue.
Many people with Parkinson’s disease complain of constant fatigue. This can be due to sleep disturbances (such as insomnia, sleep apnea, nightmares or acting out dreams while asleep), which are associated with the disease. The feeling of persistent tiredness can also be due to disease-related depression, akinesia (difficulty in starting a movement) or muscle fatigue or disease medications.
Compromised cardiac function results in the heart’s inability to pump sufficient blood throughout the body. The underlying cause may be either unhealthy cardiac tissue, congenital heart defects, heart rhythm problems, malfunctioning cardiac valves or blocked coronary arteries. Because of this impaired flow of nutrient-rich blood to the body’s tissues, fatigue results.
Both insomnia and daytime sleeping are common symptoms of Alzheimer’s disease, possibly due to the buildup of amyloid plaques in the brain.
People with cancer frequently complain of a loss of energy and almost constant fatigue. That’s due to the negative metabolic effects that the fast-growing cancer cells have on the body as they hijack the energy and resources necessary for other body processes.
Dr. Rothschild has been a faculty member at Brigham and Women’s Hospital where he is an Associate Professor of Medicine at Harvard Medical School. He currently practices as a hospitalist at Newton Wellesley Hospital. In 1978, Dr. Rothschild received his MD at the Medical College of Wisconsin and trained in internal medicine followed by a fellowship in critical care medicine. He also received an MPH in 1998 from the University of Pittsburgh School of Public Health. Dr. Rothschild was a health services researcher at Brigham and Women with a focus on patient safety, quality improvement and information technology. More recently he was the Clinical Device Director for Partners Healthcare System integrating biomedical devices and physiologic monitors with the enterprise electronic health record.