Everyone feels tired sometimes. A late night, hard work, family responsibilities, or stress can all reduce energy.
Older adults may also notice they become tired more often than when they were younger. However, feeling exhausted every day is different from normal tiredness.
When fatigue lasts for a long time, it may be your body’s way of warning that something is wrong.
Doctors say persistent fatigue has many possible causes. While poor sleep, stress, and anemia are well-known reasons, several hidden health conditions can also leave people feeling drained without obvious symptoms.
One of these conditions is hypothyroidism.
The thyroid gland produces hormones that control the body’s metabolism, which is how the body turns food into energy. When hormone levels become too low, many body functions slow down.
Besides tiredness, people may notice weight gain, slower thinking, feeling cold, or depression. A 2019 study found that fatigue can appear early, even before other symptoms become clear.
Another condition is adrenal insufficiency. The adrenal glands produce cortisol, an essential hormone that helps maintain energy and respond to stress.
Low cortisol levels can lead to ongoing tiredness, muscle weakness, dizziness, and low blood pressure. Because the symptoms are not specific, diagnosis may be delayed.
The heart also affects energy levels. If the heart cannot pump blood efficiently, muscles and organs receive less oxygen. Instead of chest pain, some older adults mainly experience unusual fatigue. Research published in 2021 found that unexplained tiredness may sometimes be an early clue to heart disease.
Inflammation throughout the body can also leave people exhausted. Autoimmune diseases such as lupus and rheumatoid arthritis keep the immune system active all the time. This constant activity uses large amounts of energy.
A 2018 study reported that fatigue is one of the symptoms that most affects daily life in people with these illnesses.
Nutrition matters too. Vitamin D, vitamin B12, and iron all help the body produce energy. Low vitamin D is especially common in older adults because many spend less time outdoors. Research published in 2020 linked low vitamin D levels with weakness and reduced energy.
Some people feel tired because they never get deep, refreshing sleep. Sleep apnea interrupts breathing many times during the night. Even though a person may not remember waking up, their brain repeatedly leaves deep sleep. A 2021 review found that untreated sleep apnea increases daytime sleepiness and can also raise the risk of other health problems.
Because many illnesses share fatigue as a symptom, doctors often recommend blood tests, heart examinations, or sleep assessments when tiredness continues. These tests can identify treatable conditions before they become more serious.
Persistent fatigue should not be accepted as a normal part of aging. Paying attention to changes in energy levels and seeking medical advice early can lead to faster diagnosis, better treatment, and a healthier, more active life.
If you care about wellness, please read studies about how ultra-processed foods and red meat influence your longevity, and why seafood may boost healthy aging.
For more health information, please see recent studies that olive oil may help you live longer, and vitamin D could help lower the risk of autoimmune diseases.
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