Unexpected Causes of Tiredness

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Christy Matta M.A. is a trainer, consultant and writer. She is the author of “The Stress Response: How Dialectical Behavior Therapy Can Free ...Read More

Everyone experiences periods of tiredness and fatigue at times in their lives. It can feel as if it comes from nowhere, or build slowly over time.

Fatigue can make life difficult. When you’re tired it’s harder to think through complex tasks, memory is impaired and you often don’t have the energy to complete daily chores or responsibilities. On the job, fatigue can have disastrous results. Eighty-six percent of New Zealand anaesthetists report making a fatigue related error in their career, 30 to 40% of heavy trucking accidents are fatigue related (US National Transport Service) and lack of alertness and dozing accounts for 53 percent of groundings, according to the Japanese Maritime Research Institute. Tiredness can stem from medical conditions, such as anemia, persistent pain, sleep apnea of an underactive thyroid. Psychological conditions, such as depression, anxiety and grief can also cause fatigue.

But often, when people are tired all the time, it’s due to factors in every day life. Most know that nighttime waking, inactivity and stress can wear you out. Sometimes our fatigue and difficulties with sleep caused by the very things we try to do to improve sleep.

If you’re often tired, consider whether any of the following may be contributing to your fatigue:

Alcohol use or abuse: Many people who experience sleep problems, drink alcohol in the evenings for the sedating effects. During normal sleep, a person goes through two alternating states of sleep characterized by different types of brain waves. Most time is spent in a deep restful sleep, but a certain portion of the night is spent in REM sleep, during which time dreams occur. It is not fully understood why, but REM sleep is essential to health. In animal studies, deprivation of REM sleep lead to death in a matter of weeks.

Although it may decrease the time it takes to fall asleep, alcohol consumed within an hour of bedtime can disrupt REM sleep, causing fitfulness, waking from dreams and difficulty returning to sleep. These nighttime sleep disturbances lead to daytime sleepiness and fatigue.

Cold Medicine: Cold symptoms tend to worsen at night, so taking a cold medicine should improve symptoms and help you sleep. But, depending what you take, it could make sleep worse. Medications affect people differently. For some, decongestants in cough and cold pills can cause jitteriness. A cold in combination with a medication that causes jitteriness can leave you fatigued during the day.

Excessive physical activity: It is generally believed that exercise improves sleep. And regular vigorous exercise can decrease sleep disturbances. The research on sleep and exercise indicates that it is associated with less daytime tiredness, less total sleep time and awakening less tired.

However, as with many things in life, taking exercise to excess can leave you feeling fatigued. When you work out intensely, the body needs time to rest and regenerate. Loss of electrolytes and dehydration can lead to tiredness. Signs you are overdoing a workout include whole body exhaustion, weak arms and legs and difficulty standing.

If your tiredness seems to have no cause, it may be due to an underlying medical condition. However, it is often our daily habits that are causing tiredness.