Fatigue — Causes and Solutions

Fatigue — Causes and Solutions

Do you always feel tired and exhausted? Constant fatigue has many causes, from food intolerances and vitamin B12 deficiency to metabolic disorders or too much caffeine consumption. In this article, CARE provides a guide to constant fatigue and tiredness. Together, we'll examine the potential causes and solutions to help you regain vitality.

Blog Author Elena Health Coach at CARE
Elena Iagovitina

Health Coach

Published in Sleep
9 min read · Apr 24, 2024

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Why Am I Always Tired?

Feeling tired all the time can be a complex phenomenon caused by a variety of biological factors. Sleep, dietary habits, hormonal imbalances, your lifestyle, or certain illnesses can lead to a persistent feeling of tiredness and fatigue. [1] [2]

Biologically, fatigue can be caused by various processes in the body, particularly the interaction of neurotransmitters such as adenosine, which accumulates in the brain throughout the day and promotes drowsiness. In addition, your body reacts to your biological clock, the circadian rhythm, and external light influences, which together control the sleep-wake cycles. Basically, fatigue serves as a natural signal from the body that rest and recovery are needed — there can be many reasons why your body asks for rest. [3]

Your body may need rest to repair body cells, strengthen the immune system, or support cognitive functions such as memory and learning. Maybe you even have bloating and a disrupted gut flora that rob your body of energy. The reasons why you are fatigued can therefore be very diverse.

The physiological sign of tiredness aims to help you maintain your health and performance in the long term. If you are fatigued all the time, you should find out where the exhaustion and fatigue have their roots.

What Are the Causes of Constant Fatigue?

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CARE has summarized possible causes of constant tiredness and fatigue:


For many people, sleep is central to constant fatigue. Quality, duration, and regularity of sleep are crucial for the recovery of the body and mind. Insufficient or disrupted sleep, such as sleep apnea, blue light from screens, or insomnia, can lead to chronic fatigue.

Not getting enough sleep can disrupt your internal clock – your sleep-wake cycle – and can lead to fatigue over an extended period of time. [4]

Hormonal Imbalances

Hormonal imbalances also play an important role in fatigue. For example, hypothyroidism, which is associated with reduced levels of thyroid hormones, can lead to constant fatigue. Similarly, low testosterone levels in men and changes in estrogen and progesterone levels in women can cause fatigue. [5]


Another biological cause of constant fatigue is anemia, a lack of red blood cells that leads to insufficient oxygen supply to the organs. This can noticeably lower energy levels and cause persistent fatigue. [6]

Chronic Inflammation & Autoimmune Diseases

Chronic inflammation and autoimmune diseases such as rheumatoid arthritis or lupus can also lead to constant fatigue as the body constantly fights against these inflammations. [2]

Diet & Nutrition

The diet also has a significant impact on your body's energy levels. An unbalanced diet comprised of processed foods (chicken nuggets, pizza, etc.) and low in essential nutrients (omega-3 fatty acids, vitamins, proteins) can lead to a lack of energy and, therefore, fatigue. [2]

Post-viral Fatigue Syndrome

Post-viral fatigue syndrome, also known as post-viral exhaustion syndrome, leads to persistent fatigue after a viral infection such as COVID-19. This condition is characterized by a persistent immune response that remains active even after the actual infection has subsided. [7]

In this state, your body uses a lot of energy for immune activity, which leads to persistent exhaustion and fatigue. In addition, inflammatory processes in the body can affect the nervous system and further increase tiredness.

Iron Deficiency

An iron deficiency can also lead to fatigue, as iron plays an essential role in producing hemoglobin, a component of red blood cells responsible for transporting oxygen throughout your body. With a lack of iron, the body cannot produce enough hemoglobin, resulting in a reduced oxygen supply to organs and tissues. [2]

This insufficient oxygen supply means cells cannot work efficiently, leading to weakness and fatigue. Chronic iron deficiency can also affect muscle and brain function, further increasing feelings of fatigue.

Vitamin B12 Deficiency

A vitamin B12 deficiency can lead to fatigue, as this vitamin is crucial for the production of red blood cells that transport oxygen throughout the body. A lack of vitamin B12 can lead to a form of anemia known as pernicious anemia, which affects the oxygen supply to cells, causing fatigue and weakness. [2]

In addition, vitamin B12 is important for the function of the nervous system and efficient energy metabolism. A deficiency can, therefore, cause neurological symptoms and reduced energy production, further increasing the feeling of fatigue.

With a health check-up at CARE you can determine your vitamin B12 level and many other important biomarkers.

Caffeine Consumption

Caffeine, which is found in coffee, certain teas, and energy drinks, works by blocking the adenosine receptors in your brain. Adenosine is a neurotransmitter that builds up in your brain throughout the day (when you're awake). Adenosine triggers feelings of sleepiness and relaxation and naturally increases by the evening to make you tired and prepare your body and brain for sleep. However, caffeine blocks these adenosine receptors and prevents the adenosine from docking onto them and making you sleepy. Over the course of the day, more and more adenosine accumulates in your brain. Incidentally, while you sleep, your brain breaks down the adenosine again. [8]

However, with regular and high caffeine consumption, your body can no longer break down the adenosine accumulated throughout the day while you sleep, so you wake up tired.

Lack of Exercise

A lack of regular physical activity can lead to decreased physical fitness and reduced cardiovascular efficiency. This, in turn, can affect blood flow and oxygen supply to the body and brain, leading to fatigue and a general lack of energy. In addition, lack of exercise can lead to poorer quality sleep, which further exacerbates fatigue. [2]


With an underactive thyroid (hypothyroidism), the thyroid gland does not produce enough of the hormones required to regulate metabolism. This leads to a slowdown in various bodily functions, including energy production and heart rate, which manifests in fatigue and weakness. People with hypothyroidism often experience persistent fatigue, even after adequate sleep. [2]

Chronic Fatigue Syndrome (CFS)

Chronic fatigue syndrome (CFS) is a complex disorder characterized by extreme, persistent fatigue that does not improve with rest and severely limits daily functioning. [2]

The exact causes of CFS are not fully understood, but immune system disorders, hormonal imbalances, and nervous system disorders are thought to play a role. Patients with CFS often also experience other symptoms, such as muscle pain, memory problems, and sleep disturbances, which further exacerbate fatigue.

Mental Health Issues

Low moods and psychological illnesses exhibit neurochemical and hormonal imbalances in the brain that can affect motivation and energy, which can lead to constant fatigue. Neurotransmitters such as serotonin and dopamine, which are essential for mood and sleep regulation, can be imbalanced in depressed mood, resulting in a lack of energy and fatigue. [2]

In addition, a lack of drive that often accompanies depressive moods or mental health issues exacerbates the situation, as less physical activity leads to lower endorphin production.


Seasonal allergies such as hay fever can also lead to constant fatigue, as the body's immune response to allergens consumes a lot of energy and causes inflammatory processes that can lead to exhaustion. [9]

In addition, some allergy medications, especially older antihistamines, can lead to typical symptoms such as fatigue as a side effect. Respiratory problems caused by allergies, such as blocked nasal passages or asthma, can also disrupt sleep, leading to inadequate rest and persistent fatigue.

What Can I Do to Combat Fatigue in Everyday Life?

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To effectively combat your fatigue in everyday life, you can consider the following measures: [10]

  • Regular sleep: Try to go to bed and get up at the same time every day to stabilize your circadian rhythm and prevent sleep deprivation. Make sure you get, at best, 7-9 hours of restful sleep per night.

  • Eat a balanced diet: Eat nutritious foods rich in iron, vitamin B12, magnesium and omega-3 fatty acids. Avoid heavy, sugary, or very fatty meals, which can boost your energy in the short term but lead to a drop in energy later on.

  • Exercise regularly: Moderate physical activity, such as a daily walk or light jog, can improve blood circulation and boost your energy.

  • Hydration: Drink enough water; even mild dehydration can lead to fatigue.

  • Reduce caffeine and alcohol: Avoid excessive caffeine consumption, especially in the afternoon and evening, and reduce alcohol consumption, as both can interfere with sleep. Pro-tip: Only drink your first cup of coffee 60–90 minutes after waking up.

  • Stress management: Relaxation techniques such as meditation, yoga, or simple breathing exercises can help you reduce stress, which is a common cause of fatigue.

  • Take breaks outdoors and in the sun: Take short breaks in the fresh air during the day to relax and rejuvenate, especially if you work long hours, sit at a desk, or study for an exam. Outdoor breaks can help you manage your energy healthily and replenish your vitamin D levels. Vitamin D plays an important role in energy production as it aids calcium absorption and improves muscle function, which can help you feel more energized. [11]

  • Power nap: A short nap of about 20 minutes can help you improve your mental clarity and alertness without dipping into deeper stages of sleep that could lead to sleep inertia. This short rest can refresh energy levels, effectively counteracting fatigue during the day.

  • Legumes: Legumes such as lentils, beans, and chickpeas are rich in complex carbohydrates and proteins that provide a slow and steady source of energy. This helps to keep blood sugar levels stable and avoids the fatigue that occurs after eating simple sugars.

  • Folic acid: Folic acid, an essential B vitamin found in green leafy vegetables, nuts, and whole grains, supports the formation of red blood cells and can help prevent fatigue. A deficiency of folic acid can lead to anemia, which is associated with increased fatigue, so getting enough of this vitamin can help increase energy and reduce fatigue.

Incorporating these tips into your daily routine can increase your energy and improve your quality of life. Your health coach at CARE can also help you to develop customized strategies to combat constant fatigue.

When Should I See a Doctor About Fatigue?

You should see a doctor if your fatigue persists despite getting enough sleep, eating healthily, and exercising regularly, or if it comes on suddenly and severely affects your daily life.

It is also important to seek medical advice if your fatigue is accompanied by other symptoms such as weight changes, pain, or mood swings.

How Can Constant Fatigue Be Treated?

Treatment for fatigue starts with diagnosing the cause of your fatigue. The blood tests at CARE will give you an insight into your current state of health and can identify anemia, nutritional deficiencies, and other potential causes of your fatigue.

Many of our CARE members have been able to identify iron deficiencies, vitamin deficiencies, or hormonal imbalances that they were previously unaware of.

Based on your individual health data, our health coaches can provide you with a targeted strategy on how to optimize your energy levels and overall health, for example, by supplementing nutrients or changing lifestyle habits.

We will be happy to explain measures such as sleep management, nutritional optimization, and stress reduction to improve your quality of life and combat your constant fatigue. Book your health check-up now! 

List of References

Blog Author Elena Health Coach at CARE

Elena Iagovitina

Health Coach at CARE Zurich

About the author

Elena is an enthusiastic Health Coach and blog writer at CARE, with a passion for holistic medicine and health. Previously, Elena worked for almost five years as a coach leading retreats, workshops, and seminars. These included mind-body therapy: breath work, meditation, and massage; as well as energy force therapy: reiki, and qi gong; and third expressive therapy: movement, writing and support groups. Elena shares exciting articles on the blog, on the topic of where the alternative and traditional medicine intersect with Western Medicine. Elena is also the driving force behind the CARE community. In her spare time, she enjoys hiking, traveling to remote locations and dancing. You might also see her on the lake of Zurich as a coast guard. Join her on her journey to learn more about health and discover the world of preventive medicine! Visit all articles written by Elena!