People come to me because of weight gain, hormonal changes, or digestive problems, but the vast majority also struggle with FATIGUE.
Let’s assume a good provider has already ruled out the most common medical causes of fatigue—like anemia, hypothyroid, rheumatoid arthritis, or diabetes.
Now let’s assume the fatigue is still there.
Here are 10 lesser-known causes of fatigue I look for as a functional medicine practitioner:
1️⃣ Medication Side Effects
Blood pressure medications, statins, antidepressants, antihistamines, and proton pump inhibitors can all cause fatigue.
2️⃣ Micronutrient Deficiencies
Nutrients needed for energy production include vitamin B12 and other B vitamins, iron, magnesium, and vitamin D.
3️⃣ Mitochondrial Function
Mitochondria are the powerhouse of the cell, but they can become damaged by things like pollutants, environmental toxins, infections, medications, or nutrient deficiencies.
What some call “adrenal fatigue” is more specifically a dysregulation of the HPA axis. It happens when chronic stress exhausts both the adrenal glands and the nervous system.
5️⃣ Stealth Infections
Lyme disease, EBV, fungal infections, or mold disrupt the immune system and contribute to fatigue.
6️⃣ Gut Problems
SIBO, IBS, and other digestive issues interfere with the absorption of nutrients needed for energy.
Cortisol, DHEA, estrogen, progesterone, testosterone, and thyroid hormone all affect energy.
Both too much and too little exercise can leave the body feeling drained and exhausted.
Caffeine, sugary drinks, and alcohol put a strain on the nervous system and hormones.
🔟 Emotional Stress
Everything from anxiety to depression to just plain boredom can cause fatigue.
The point is that “fatigue” does not have one clear cause. We need to do the detective work to find the source in each beautifully unique individual.