Understanding and Addressing Fatigue with Functional Medicine

Functional medicine July 2, 2024
What we’ll cover

    Fatigue is a common reason many seek medical care. It is characterised by an extreme lack of energy that affects daily functioning. 24% of adults report experiencing fatigue, with two-thirds unable to identify its cause. While conventional lab results influence medical management in only 5% of cases, functional medicine offers a more comprehensive approach by delving into lifestyle factors and the body’s complex systems.

    What is Fatigue?

    Fatigue can be classified into three types:

    1. Secondary Fatigue: Caused by an underlying medical condition, generally lasting less than six months.
    2. Physiologic Fatigue: Resulting from lifestyle imbalances; usually resolves with rest and minimally impacts daily activities.
    3. Chronic Fatigue: Lasts longer than six months and is not improved by rest.

    Symptoms of Fatigue

    Fatigue symptoms can vary, making it essential to understand how patients describe their fatigue. Common symptoms include:

    • Lack of energy
    • Drowsiness
    • Weakness
    • Changes in mood (depression, anxiety, irritability)
    • Trouble concentrating
    • Low motivation
    • Muscle and joint pain

    Causes of Fatigue

    Fatigue can arise from various factors, including:

    • Lifestyle Factors include poor sleep, diet, mental stress, a sedentary lifestyle, excessive exercise, and environmental exposures (e.g., lead, and mercury).
    • Medical Conditions: Almost every disease can present with fatigue as a symptom, such as:
      • Acute Causes: Medications, anemia, mental stress, depression.
      • Subacute Causes (1-6 months): Diabetes, hypothyroidism, sleep apnea, cancer.
      • Chronic Causes (over 6 months): Postviral fatigue, chronic fatigue syndrome (CFS), substance abuse.
    • Sleep Disorders: Insomnia, sleep apnea, narcolepsy.
    • Medications: Antihistamines, muscle relaxants, antidepressants, beta-blockers, opioids.
    • Environmental Exposures: Lead, mercury, carbon monoxide.

    Functional Medicine Labs for Fatigue

    A comprehensive evaluation includes a thorough review of medications, supplements, sleep routine, exercise, and substance use. Key tests include:

    1. Complete Blood Count (CBC): Screens for anemia, infection, and nutritional deficiencies.
    2. Comprehensive Metabolic Panel (CMP): Measures blood glucose, electrolytes, liver, and kidney function.
    3. Hemoglobin A1c (HbA1c): Monitors blood sugar levels over three months.
    4. Thyroid Panel: Assesses thyroid function and detects hypothyroidism.
    5. Iron Panel: Diagnoses iron deficiency and anemia.
    6. Erythrocyte Sedimentation Rate (ESR): Indicates inflammation.
    7. Urinalysis: Screens for infections, kidney disease, and diabetes.
    8. Pregnancy Test: For women of reproductive age.

    Specialty testing may include:

    • Comprehensive Hormone Assessment: Evaluates cortisol and melatonin levels.
    • Food Sensitivities: Identifies adverse food reactions.
    • Nutritional Testing: Measures vitamins, minerals, and metabolic markers.

    Conventional vs. Integrative Treatment for Fatigue

    Conventional Treatment focuses on addressing the underlying cause of secondary fatigue, lifestyle modifications for physiologic fatigue, and symptom management for chronic fatigue. This may include medications, structured exercise routines, and stimulants for short-term alertness.

    Integrative medicine combines conventional methods with nutritional therapy, botanical medicine, and supplements to address underlying imbalances and support long-term energy improvement. Key approaches include:

    • Anti-inflammatory Diet: Rich in omega-3 fatty acids, antioxidants, polyphenols, and protein.
    • Micronutrient Support: Supplements like B vitamins, vitamin D, CoQ10, glutathione, iron, magnesium, and zinc.
    • Herbal Supplements: Adaptogenic herbs (ashwagandha, Rhodiola, ginseng) and nervines (skullcap, oat, valerian).
    • Lifestyle Modifications: Regular exercise, limited caffeine intake, and improved sleep hygiene.


    Addressing fatigue through functional medicine involves identifying and treating the root cause while providing symptomatic relief through a holistic approach. By integrating lifestyle modifications, dietary changes, and targeted supplements, patients can achieve significant and lasting improvements in their energy levels and overall health.