Fatigue: Causes, Symptoms, and Ways to Improve Energy Levels

What Is Fatigue?

Fatigue refers to the feeling of tiredness or lack of energy that can interfere with daily activities and does not recede with rest.

Feeling tired from physical exertion, lack of sleep, or a particularly demanding day is normal. However, when tiredness persists and begins impairing your ability to perform daily activities, it may need attention.

What Causes Fatigue?

Fatigue can have many different causes, ranging from lifestyle factors such as not getting enough sleep to medical conditions that require treatment. Sometimes more than one factor can contribute to the way you feel.

Some of these causes are temporary and may improve with changes to your daily routine, while others may need medical attention.

Lifestyle Factors

Your fatigue can be a result of a demanding routine. Work schedules, ongoing stress, and inadequate nutrition can all contribute to it.

These factors can also overlap, with one affecting another, making fatigue more prominent.

• Working late: Regularly working late can reduce the amount of time available for adequate sleep and recovery.
• Working night shifts: Night or rotating shifts can disrupt your natural sleep-wake cycle and make it harder to maintain consistent energy levels.
• Inadequate nutrition: Not getting enough of the nutrients your body needs can affect energy levels and may contribute to fatigue.
• Excessive alcohol consumption: Drinking too much alcohol can interfere with sleep and leave you feeling tired or low on energy.
• Burnout: Prolonged physical, mental, or emotional demands can leave you feeling exhausted and make it harder to maintain your usual level of functioning.
• An inactive lifestyle: Spending long periods without physical activity may contribute to low energy and fatigue.

Health Conditions

Several health conditions can cause or contribute to fatigue, particularly when they affect sleep, hormone levels, metabolism, or the nervous system.

Sleep Disorders

A study found that sleep disorders such as insomnia, sleep apnea, and narcolepsy are the most prevalent causes of fatigue. These conditions can interfere with the quality or regulation of sleep, which can leave you feeling tired during the day.

Chronic Fatigue Syndrome

Myalgic encephalomyelitis, also called chronic fatigue syndrome, is a complex, long-term condition that causes severe fatigue that often worsens with physical activity.

While the exact cause of the condition remains unknown, genetics and issues with nutrient absorption are speculated as possible factors.

Infections

Viral and bacterial infections, such as COVID-19, influenza, and pneumonia, can also leave you feeling fatigued.

Mental Health Conditions

After sleep disorders, research suggests that depression is the next most common cause of fatigue. Other mental health conditions such as anxiety and post-traumatic stress disorder (PTSD) can also be associated with persistent tiredness.

Heart Conditions

Heart disease and heart failure can cause fatigue when the heart cannot circulate blood as effectively as the body needs.

Lung Conditions

Conditions that affect breathing or oxygen exchange, including chronic obstructive pulmonary disease (COPD) and emphysema, can contribute to persistent tiredness. Asthma may also leave you fatigued, particularly when symptoms interfere with sleep or breathing.

Autoimmune Disorders

Conditions in which the immune system mistakenly attacks your body’s healthy cells can also cause fatigue. Some common examples include multiple sclerosis (MS), myasthenia gravis, and rheumatoid arthritis.

Hormonal Imbalances

Certain hormonal conditions, such as hypothyroidism and diabetes, are also associated with fatigue. Pregnancy can also bring hormonal changes that may contribute to feeling tired, particularly during the early stages.

Chronic Conditions

Long-term conditions such as chronic kidney disease, cancer, and type 2 diabetes may cause fatigue through changes in metabolism, inflammation, organ function, or the effects of treatment.

Deficiencies

Deficiencies of iron and certain nutrients such as vitamin B12 or vitamin D can also lead to fatigue.

Medications

Fatigue can also be a side effect of certain medicines. Its intensity, however, can vary from person to person and may also depend on the dose and other medications being taken alongside it.

The following are a few medicines that may contribute to fatigue:

• Antidepressants
• Anxiety medicines
• Steroids
• Antihistamines (medications to treat allergic reactions)
• Sedatives

Is There a Connection Between Fatigue and Gut Health?

Research suggests that there may be a connection between gut health and fatigue. One study involving people with inflammatory bowel disease (IBD) found that fatigue was associated with changes in gut microbiome composition and alterations in the metabolism of certain amino acids.

The key issue here could be with digestion. When your digestive system does not absorb nutrients properly, your body may not get enough of the nutrients it needs to produce energy. This can leave you feeling tired.

Ayurveda also connects digestive health with energy and fatigue. As per Ayurveda, Agni, which refers to the body’s digestive fire and is believed to support the digestion of food, absorption of nutrients, and conversion of nourishment into energy.

According to Ayurvedic principles, factors such as an imbalanced diet, ongoing stress, poor sleep, and emotional strain can weaken Agni. This is thought to contribute to the buildup of Ama, a concept describing metabolic waste that Ayurveda associates with heaviness, sluggishness, lethargy, and fatigue.

What Does Fatigue Feel Like?

A persistent tiredness that does not go away with rest and makes everyday tasks feel challenging is a common fatigue symptom that you may experience.

Along with it, you may also notice the following symptoms, which generally accompany fatigue:

• Low mood or reduced interest in activities you usually enjoy
• Difficulty concentrating or staying focused
• Low energy or motivation
• Anxiety, nervousness, or irritability
• Muscle aches, pain, or weakness

You may also notice more physical or general sensations, such as the following:

• Heavy or tired eyes
• Tired or heavy legs
• An overall feeling of exhaustion
• Stiff or tense shoulders

When Should You Consult a Doctor?

Consult a doctor if your fatigue is persistent, unexplained, worsening, or making it difficult to manage your normal daily activities. Occasional tiredness can happen after poor sleep, illness, travel, changes in routine, or other temporary disruptions, but ongoing fatigue deserves closer attention.

Consider speaking with a healthcare professional if you notice the following symptoms:

• Your fatigue continues for several days or keeps returning.
• It is interfering with work, school, exercise, or everyday activities.
• You cannot identify an obvious reason for feeling tired.
• The fatigue appears suddenly or becomes unusually severe.
• You are experiencing unexplained weight loss alongside fatigue.

Fatigue can occasionally occur with a more serious health problem. Seek urgent medical attention if severe or unusual fatigue occurs with symptoms such as the following:

• Chest pain
• Difficulty breathing
• A very fast, slow, or irregular heartbeat
• Feeling of fainting
• A severe headache
• Severe abdominal, pelvic, or back pain
• Vomiting
• Muscle weakness

How Can You Treat Fatigue?

The right treatment for fatigue depends on what is causing it. If an underlying medical condition or medication is responsible, treating or managing that cause is more important than trying to treat fatigue as an isolated symptom.

When fatigue is related to lifestyle factors, a few practical changes, such as the following, may help support more consistent energy levels:

Getting Quality Sleep

Consistent, restorative sleep gives your body time to recover and can make daytime energy more stable. Aim for 7-9 hours of sleep each night and try to maintain similar sleep and wake times.

Give yourself time to wind down before bed. Reducing screen exposure and choosing a relaxing activity can help create a transition into sleep.

Staying Physically Active

Regular movement can support physical fitness, circulation, mood, and energy. If you have been inactive, begin with manageable activities such as walking and gradually increase the duration or intensity as your body adjusts.

Choose activities that feel sustainable rather than forcing yourself through severe exhaustion. Give yourself adequate recovery time when your body needs it.

Nourish Your Body

Your body needs adequate fluids and a balanced supply of nutrients to support normal energy metabolism.

Rather than relying on quick sources of energy, build meals around a combination of whole grains or other complex carbohydrates, protein, healthy fats, fruits, and vegetables.

Manage Stress

Prolonged stress can be exhausting, particularly when it begins to affect sleep, eating habits, concentration, or daily routines.

You can try to manage your stress levels with the help of the following practices:

• Practicing mindfulness, meditation, or slow breathing exercises.
• Setting realistic boundaries around work and other responsibilities.
• Spending time with loved ones.
• Spending time doing activities that you enjoy.

Consider speaking with a mental health professional if stress feels difficult to manage on your own.

Mool Health’s Perspective on Fatigue

Fatigue caused by an underlying disease needs appropriate medical intervention. But when there is no disease or prescription medication that explains the fatigue, it is worth looking at the factors that may be affecting your energy, including your gut health.

At Mool Health, we believe that understanding your gut health can be an important part of understanding your overall well-being. When gut health is affected, it can hinder nutrient absorption and affect how your body receives and uses the nutrients it needs.

Take the Mool Health Gut Test to learn more about your gut health and find out what it needs to improve your energy levels.

References

• https://health.stonybrookmedicine.edu/why-am-i-so-tired-causes-of-fatigue-and-how-to-get-your-energy-back/
• https://medlineplus.gov/fatigue.html
• https://www.hydroassoc.org/overcoming-fatigue/
• https://pmc.ncbi.nlm.nih.gov/articles/PMC8839554/
• https://advances.massgeneral.org/digestive-health/journal.aspx?id=1984
• https://www.fau.edu/marcusinstitute/blog/signs-of-bad-gut-health/
• https://my.clevelandclinic.org/health/symptoms/21206-fatigue
• https://my.clevelandclinic.org/health/diseases/17720-myalgic-encephalomyelitis-chronic-fatigue-syndrome-me-cfs
• https://www.mayoclinic.org/symptoms/fatigue/basics/causes/sym-20050894