Understanding Fatigue: Common Root Causes and What to Test
Fatigue is common, but it isn't something to accept as normal.
Whether you're waking feeling unrefreshed, prone to afternoon crashes, or adjusting your day around low energy, it's worth paying attention. These patterns usually point to something deeper.
Common Root Causes of Fatigue
It's not uncommon for fatigue to have multiple contributing factors, which often need to be addressed together to fully restore energy levels.
Chronic stress
Sleep issues
Blood sugar imbalance
Nutrient deficiencies
Thyroid dysfunction
Gut dysfunction
Chronic inflammation
Hormonal imbalances
Chronic infection
Environmental exposures
Medication side effect
Lab Tests to Consider for Fatigue
Work-up should be guided by a healthcare provider and tailored to your unique symptoms and health history.
Complete blood count (CBC)
Comprehensive metabolic panel (CMP)
Full thyroid panel – TSH, free T3, free T4
Iron panel including ferritin
Vitamin B12
Vitamin D
Fasting glucose and insulin
Hemoglobin A1c
Cortisol
Sex hormones – estradiol, progesterone, testosterone, DHEA-S
Inflammatory markers – CRP, ESR
Advanced Testing Options for Persistent Fatigue
Carroll food intolerance test
DUTCH test for assessment of sex and adrenal hormones
Comprehensive stool analysis to identify gut infection and/or imbalances
Urine test for mold and other environmental exposures (chemicals, heavy metals, etc.)
Non-Negotiable Foundations for Energy Support
These simple yet essential foundations must be in place to meaningfully address other root causes of fatigue.
Sufficient calorie intake, spaced throughout the day
Adequate protein with each meal, especially breakfast
Proper hydration – approximately half your body weight in ounces, more with exercise
Daily time outside, even if it's just a short walk
Consistent sleep schedule, going to bed and waking around the same time each day
