10 Lesser-Known Causes of Fatigue

🥱 Is it normal to be tired all the time?

Here are some things I often hear from new patients coming to me for help with functional medicine:

➡️ Some battle the snooze button every morning, only to drag themselves out of bed with their mind set on one thing—coffee.

➡️ Others crash in the afternoon with brain fog and trouble concentrating, pushing through until they can go home to their couch.

➡️ Most know they’d feel better with more exercise and healthier foods but can’t find the motivation to do it.

Fatigue is so common that it can seem to be the norm.

❌ But it’s not normal ❌

A Functional Approach to Fatigue

Caffeine and sugar habits to power through the day are so common that it can feel like being tired is the norm.

But fatigue is not normal.

There are dozens of medical explanations for fatigue (like anemia, diabetes, or thyroid disease), but when all those tests come back normal, there are still dozens of other reasons I investigate in naturopathic medicine.

⬇️ Why am I so tired? ⬇️

Patients 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 doctor 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 naturopathic doctor:

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.

4️⃣ “Burnout”

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.

7️⃣ Hormones

Cortisol, DHEA, estrogen, progesterone, testosterone, and thyroid hormone all affect energy.

8️⃣ Over-Exercising

Both too much and too little exercise can leave the body feeling drained and exhausted.

9️⃣ Over-Drinking

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. I love to do detective work to find the source in each beautifully unique individual.

Rachel Oppitz, ND