Why am I tired all the time?

Does tiredness follow you round like a shadow? Here are 12 reasons you're always tired.
Published 18 September, 2018

Reaching for that 3pm coffee because you feel tired all the time? The truth is, what’s in your favourite mug may be masking the real reasons you’re forever fighting fatigue.

Most doctors agree that major causes of daytime fatigue include:

  • Lifestyle issues like lack of sleep
  • Chronic stress
  • Poor diet
  • Lack of physical activity

Here, we deep dive into 12 reasons you may be feeling fatigued.

12 reasons why you may be dozing at your desk 

1. Low sleep quality

An array of issues may plague your sleep, including too little of it, low quality, or sleep apnea, any of which can have a cascading effect on your energy and metabolism. Sleep balances your body and circadian rhythms, and regulates hormones that control everything from eating habits and cravings (ghrelin and leptin), to stress response (cortisol), growth hormone, and more. Some reasons you aren’t getting stellar sleep can include:

  • Light, specifically blue light emitted from modern gadgets with screens. Mounting research, including a study in the Journal of Psychiatric Research, points to blue light exposure two hours prior to sleep causing a decrease in overall sleep quality and making it harder to wake up. Use the blue light filter on your phone, or get an app for your computer like f.lux, which gradually dampens blue light after sundown.
  • “Sleep apnea has been linked to daytime fatigue,” says Gene Sambataro, DDS, of the Julian Center for Comprehensive Dentistry. One apneic event means airflow stops for a minimum of 10 seconds. “Sleep apnea results in very poor and fragmented sleep and an inability to achieve deep sleep. Plus, the adrenal glands are releasing adrenaline during sleep due to the ‘fight or flight’ response caused by choking and obstruction from the tongue and soft palate,” Sambataro adds.
  • Alcohol can also negatively impact quality of sleep even though it may make you sleepy, says Mladen Golubic, MD, PhD, medical director for the Center of Lifestyle Medicine at Cleveland Clinic’s Wellness Institute.

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2. Anaemia

Anaemia occurs when too few red blood cells are produced. “Red blood cells transfer oxygen, so if you don’t have enough oxygen being transported to tissues, you may feel tired,” explains Dr. Golubic. Fatigue is the number one symptom of anaemia, so it’s a common first place to look deeper, especially in women of childbearing age who are menstruating.

There are various types of anaemia, however—from iron deficiency anaemia and B12 deficiency to more rare conditions. Iron can be found in dark leafy vegetables, legumes, and even dried fruit, but “even if you’re eating a diet high in these plant foods your nutrient absorption could be off (vitamin C may enhance iron absorption), plus anyone with a chronic disease could be anaemic, too,” warns Dr. Golubic. 

3. Caffeine 

As much as you may love your beloved coffee or diet cola, caffeine later in the day can interrupt sleep, which can cause daytime fatigue. What’s more, certain medications, like the birth control pill, can prolong the effects of caffeine, says sports nutritionist and author Marie Spano, MS, RD, making a single cup of coffee last in your system for up to a full day and possibly longer. You may want to avoid your caffeine vehicle of choice after noon.

4. Poor diet 

One of the biggest nutritional culprits for causing fatigue is high sugar intake. And it’s not just sugary drinks and cakes that top the list. Sugar can be hidden even in seemingly healthy foods like sauces and cereal, energising you temporarily, and then making you feel tired shortly afterward. To avoid blood sugar spikes from hidden sugars, eat more fruits and vegetables as your carb sources, plus lean protein, healthy fats, and fewer processed foods.

Diets high in unhealthy fats from fried foods can also make you tired because ”they take a while to digest. So blood from the brain and muscles is shuttled to digestive tract to digest the fatty foods,” Spano explains.

Plus, adds Spano, “you may simply not be eating or drinking enough.” People who are trying to lose weight need to strike a balance in fueling for enough energy. And hydration is also imperative. When you’re dehydrated, you have decreased mental function and fatigue; because less water equals lower blood volume, and lower blood volume means less water going to the brain and muscles.” Water recommendations vary, but the Institute of Medicine recommends 2.7 litres daily for women and 3.7 litres for men.

Even food allergies can cause fatigue, says Kristin Kirkpatrick, MS, RDN, manager of wellness nutrition services for Cleveland Clinic Wellness Institute. They lead to inflammation, which could cause you to feel tired. To test for them, you’ll take a food allergy test; or, for improved accuracy for gluten and lactose, genetic tests may help, she adds.

5. Low vitamin D levels

Vitamin D is actually a hormone, one that can help regulate mood, energy levels, and more. Research in the North American Journal of Medical Sciences shows that fatigue is common in vitamin D deficient patients and that bringing those levels back to normal improved D-related fatigue. Get outside more to help your body produce vitamin D, or supplement with D3.

RELATED: What is seasonal affective disorder?

6. Chronic stress

Believe it or not, stress can actually be a good thing, providing motivation and focus to get things done. But when it turns into chronic stress as your foot stays glued to the gas pedal, says Dr. Golubic, it can cascade into fatigue and worse, because your body is flooded with the stress hormones. Mounting research points to benefits of regular practice of stress-relief techniques as being one of the single most important outcomes of chronic stress-related disease because stress can trigger not only fatigue, but also increase the risk of heart disease, diabetes, depression, autoimmune flare-ups, and more.

How to kick the hothead habit? Self-care practices such as meditation and/or yoga—they really do work. Startling research in the journal PLOS ONE reveals a direct connection between meditation and the turning on of genes that contribute to energy metabolism, mitochondrial function (again, related to energy), insulin secretion, and reduced genes related to inflammation and stress. “Give [meditation] a try, five minutes a day, three times a week, building up to 20 minutes a day. You may find yourself far more resilient and able to bounce back from stressful events more quickly,” Dr. Golubic says.

If meditation isn’t your thing (or in addition to it), Dr. Golubic suggests relying on friends to talk to and decompress with and to be physically active. “It doesn’t have to be running a triathlon, it can be walking, running, biking, or strength exercises. You want to have a habit of it,” he says. Every step, every muscle move counts. Find the activity you enjoy and the time of day that works for you.

RELATED: Try this 3 minute meditation

7. Thyroid disorders

Whether you are hyperthyroid (produce too much thyroid hormone) or hypothyroid (produce too little), you could be fatigued throughout the day, according to Dr. Golubic. The reason is that the thyroid regulates the body’s metabolism, or its production of energy, among other things.

Thyroid disorders are fairly common in the UK - according to the British Thyroid Foundation around 1 in 20 people are affected by thyroid disorders. This includes hypothyroidism (having an underactive thyroid) yet many people don't know they have it.

“Since fatigue is a common symptom, your doctor may test your TSH [thyroid-stimulating hormone],” says Dr. Golubic, “then he or she may look into thyroid hormone T3 and T4 levels,” and only if those are not optimal your doctor might consider looking at thyroid antibody levels, which can indicate an autoimmune thyroid condition called Hashimoto’s disease. Synthetic or natural thyroid supplements can help symptoms, as can a whole foods diet that avoids gluten, dairy, and soy, according to clinical pharmacist Izabella Wentz, Pharm.D., author of the New York Times best seller Hashimoto’s Protocol.

8. Diabetes (or prediabetes)

“Low energy can be seen with diabetes, either due to insulin deficiency or resistance to insulin,” says Jacqueline Jonklaas, MD, PhD, Professor of Medicine, Division of Endocrinology at Georgetown University. Too much blood sugar can create a groggy effect and too little means that blood cells don’t have enough energy to transport. “If diabetes is present it can be easily diagnosed. It is then treated with lifestyle modifications and medications, including insulin, and energy levels would be expected to improve,” she explains.

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9. Autoimmune disorders

Any autoimmune condition, from Hashimoto’s disease and rheumatoid arthritis to multiple sclerosis and lupus, can cause fatigue, says Dr. Golubic. For autoimmune diagnoses, your doctor will order appropriate tests.

10. Heart disease

Those with heart disease, coronary artery disease, or arrhythmias may feel tired or weakness due to reduced optimal blood flow to the body’s tissues. Reversing heart disease starts with changing your eating and exercise habits. For this you’ll have to go beyond your doctor for help. “Creating a plan for monitoring lifestyle modifications is usually a team effort involving a primary care physician, a specialist, a nutritionist, a support group, trainers, etc.,” Dr. Jonklaas says.

RELATED: 9 simple lifestyle changes for better heart health

11. Depression

Depression may affect sleep, causing you to get too much or too little, and can cause anxiety among many other symptoms, draining the energy reserves you have. Previous theories linked depression to low serotonin, but this 50-year-old hypothesis has been disproved. As it relates to fatigue, sleep disruption seems to be the major connection between depression and fatigue.

12. Chronic Fatigue Syndrome (CFS)

​CFS is defined as six or more months of extreme fatigue, and can also include loss of memory, mood changes, joint pain, and more. CFS is a diagnosis of exclusion—meaning all other medical conditions must be ruled out before a doctor can arrive at this diagnosis, and there are no exclusive tests for it,” says Deena Adimoolam, MD, endocrinologist and spokesperson for the Endocrine Society’s Hormone Health Network. Note that CFS symptoms can appear similar to those associated with more common problems like depression, anxiety, and sleep disturbances.

Reasons for being constantly tired are extensive, and some of them could have serious health implications. So instead of shrugging it off, if it's chronic or gets worse, talk to your doctor.

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