Some of the Common Causes of Fatigue

Bird on branch

Causes of Fatigue

We have all had the feeling of waking up after a night of terrible sleep. Our limbs feel heavy, our muscles ache and our thinking is cloudy. Just putting one foot in front of the other on our way to the coffee pot feels like climbing a mountain. But we know even if it won’t be for another 16 hours, we will get to climb back into bed and a night or two of good sleep will have us feeling like ourselves again.

But what if we have that feeling of leaden arms and legs and achiness without the explanation of a night of tossing and turning? What if this feeling lasts, not just a day or two, but for weeks?

Because fatigue is such a vague symptom there are many possible causes. Today we will talk about some of the most common ones.


Not Enough Sleep

Maybe it seems obvious, but so many of the people I encounter complain of fatigue, but with the next breath report they are only getting four or five hours of sleep per night. While most of us can take a day or two without enough sleep in our stride, the vast majority of us need seven to nine hours of sleep per night to feel our best.

So, step one is to take stock of your sleep, not just over a night, but over a week or two. There is technology galore to give you information about your sleep. If you wear a smart watch, there are Apps like SleepWatch that will automatically track your sleep if you wear your device to bed. There are other apps that involve keeping your phone near you at night to track breathing patterns.

But if you don’t love the idea of your phone “listening” to your breathing while you sleep, a notepad by your bed with suffice. Just record when you get into bed at night and when you get out of bed in the morning. Be sure to take an average over at least a full week. I often only sleep about six hours on Sunday and Monday nights but more than eight hours on Saturdays. I know from tracking my sleep over multiple weeks that I sleep 7.4 hours per night on average.

If you aren’t sleeping an average of 7 to 9 hours a night, it is time to figure out why and what can be done about it. Staying up too late? Set a bedtime alarm to prompt you to get in bed earlier. Kiddo up at night? Trade off managing these issues with your partner if you have one.


Poor or Disrupted Sleep

There are lots of causes of poor sleep quality. Your bedroom is noisy or your partner snores. Alcohol consumption is a common cause of disrupted sleep and limiting alcohol intake can be very helpful. Ditto for caffeine consumption, especially in the afternoon and evening.

Sometimes sleep disruption is more serious and may require help from a doctor. For women, perimenopause and menopause can be disrupt sleep even in the absence of hot flushes. A conversation with your gynecologist about treatment options is in order. For both men and women--do you snore? Asking your primary doctor about a sleep study to look for sleep apnea may help identify treatment options.


Energy Mismatch

If you are getting enough sleep and sleep quality is good, consider noticing when you feel best and when you are most tired. Try to tackle to-dos that require the most focus when you feel the most energetic and save the low energy tasks for low energy times.

If you can barely keep your head off your desk at 2 pm, know this is a normal time to have low energy. Our cortisol levels are naturally low at this time. If your schedule permits this is a great time for a nap (think of the Spanish siesta). If not, then a brisk walk or a cup of tea (or both) may help (Think of English teatime).



Next, examine your diet. Looking for patterns between diet and energy level can be revealing. Many people will feel terrible after a carbohydrate heavy meal. In fact, carbohydrates are often the culprit if you get waves of fatigue one to two hours after eating them. Decreasing the carbohydrates in your diet and focusing on meals that include a combination of high quality carbs, protein and healthy fats will often minimize carbohydrate induced fatigue.


Vitamin Deficiencies

And what if you are sleeping enough and eating well, but still find it hard to get through the day? Simple vitamin deficiencies can make us feel rotten. Iron deficiency and B12 deficiency especially can cause significant fatigue even if blood levels of these vitamins are in the low normal range. If you are struggling to make it through the day, it is worth asking your doctor to check for these deficiencies.


Anxiety and Depression

Mood disorders such as depression and in some cases, anxiety can zap energy. The biochemical changes that cause depression don’t just depress mood, but also depress our alertness, focus and motivation. At the same time, those same neurotransmitters that depress all the brain’s functions also disrupt sleep further exacerbating the fatigue we feel. If you suspect depression or anxiety are contributing to your fatigue you should reach out to your doctor or therapist immediately.


Thyroid Disease

Hypothyroidism, or an underactive thyroid, is a common cause of fatigue in people that may be missed. Hypothyroidism can develop at any time, but new hypothyroidism is especially common in the year after giving birth and around menopause. Simple blood testing can diagnose thyroid issues.


Many people will explain away their fatigue. They have a lot of responsibilities: a job, a house, kids, parents, a partner. There is always an excuse. A work presentation to stress over, a baby that is teething, a teenager out past curfew. But there comes a point where on-going tiredness deserves medical attention, so that we can feel well and enjoy our time.

While this is not an exhaustive list of causes of fatigue--if you have addressed the basics and still find yourself dragging, then perhaps it is time to consult us here at Palmetto Endocrinology.

Joseph W. Mathews, MD, FACP, FACE, ECNU, CCD Joseph Mathews, MD, FACP, FACE, ECNU, CCD Joseph W. Mathews M.D., a board certified Endocrinologist and Medical Director of Palmetto Endocrinology, was born and raised in South Carolina. He earned his Bachelor of Science in Biology from the College of Charleston, Cum Laude. He then achieved his M.D. at the Medical University of South Carolina where he also completed his residency in Internal Medicine and a Fellowship in Endocrinology, Diabetes, and Metabolism. Dr. Mathews is also a Fellow of both the American College of Endocrinology and the American College of Physicians, holds an Endocrine Certification in Neck Ultrasound (ECNU) and is a Certified Clinical Densitometrist (CCD). He has extensive experience performing ultrasound guided fine needle aspiration biopsies. His practice includes a range of specializations including prescribing and fitting patients with insulin pumps. Dr. Mathews' practice has drawn patients from out of state to benefit from his expertise in thyroid disorders, diabetes, cortisol problems and their Endocrine disorders.

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