Why Am I Always Tired? 10 Hidden Causes of Fatigue You Shouldn’t Ignore

Do you wake up feeling exhausted… even after a full night’s sleep?

Are you reaching for caffeine just to get through the day?

If you find yourself constantly asking, “Why am I always tired?”, you’re not alone. Fatigue is one of the most common complaints people bring to their doctors—and one of the most misunderstood.

In functional medicine, we believe fatigue is not a diagnosis—it's a symptom of imbalance. Rather than simply masking the exhaustion with more stimulants, we aim to uncover and address the root cause of why your energy is low in the first place.

Here are the top 10 hidden reasons you might be feeling tired all the time—and what you can do about it.

1. Thyroid Dysfunction

Your thyroid controls metabolism, energy, and body temperature. When your thyroid is underactive (hypothyroidism), even simple tasks can feel like a struggle. You may also experience cold hands, weight gain, hair thinning, and depression.

➡️ What to test: TSH, Free T3, Free T4, Reverse T3, and thyroid antibodies
➡️ How functional medicine helps: We look at the full thyroid panel, not just TSH, and address nutrient deficiencies (like iodine, selenium, and zinc) that affect thyroid function.

2. Adrenal Fatigue and Chronic Stress

Your adrenal glands help regulate cortisol, your stress hormone. When stress becomes chronic—whether from emotional strain, lack of sleep, overwork, or inflammation—your adrenals can become depleted.

Symptoms of adrenal dysfunction include:

Mid-day crashes
Salt or sugar cravings
Trouble sleeping despite exhaustion
Feeling “wired but tired”

➡️ What to test: Cortisol (saliva or urine), DHEA
➡️ Solution: Adaptogenic herbs, stress management, proper sleep, and blood sugar balance

3. Iron Deficiency or Anemia

You need iron to make hemoglobin, which delivers oxygen to your cells. Without enough, your body runs low on cellular fuel—leading to weakness, pale skin, dizziness, and heavy fatigue.

➡️ What to test: Ferritin, iron, TIBC, hemoglobin, B12, folate
➡️ Watch for: Fatigue in women with heavy menstrual cycles, vegans/vegetarians, or post-surgery patients
➡️ Fix it naturally: Include iron-rich foods (grass-fed beef, spinach, lentils) and pair with vitamin C for absorption

4. Blood Sugar Imbalance

Constant blood sugar swings—from too many refined carbs or skipping meals—can create energy crashes, irritability, brain fog, and intense cravings.

➡️ What to test: Fasting insulin, HbA1c, glucose, continuous glucose monitoring (CGM)
➡️ Signs: Energy dip after meals, waking up at 3 AM, intense hunger
➡️ Functional fix: Eat balanced meals with protein, fat, and fiber; reduce refined carbs and sugar

5. Poor Sleep Quality

Quantity is not the same as quality. If you have sleep apnea, restless leg syndrome, or high cortisol at night, your sleep may not be restorative—even if you're in bed for 8 hours.

➡️ What to explore: Overnight sleep study, wearable sleep trackers, cortisol rhythm testing
➡️ Common culprits: Alcohol, blue light, stress, poor sleep hygiene
➡️ Support: Magnesium glycinate, melatonin, lifestyle routines, adrenal support

6. Gut Imbalances and Inflammation

Your gut is the gateway to nutrient absorption and immune regulation. If you're struggling with leaky gut, dysbiosis, or chronic infections like Candida or SIBO, you may feel tired—even if labs look normal.

➡️ Symptoms to watch: Bloating, constipation, brain fog, joint pain, food sensitivities
➡️ Functional testing: GI-MAP, stool analysis, SIBO breath test
➡️ Healing approach: Remove infections, repair the gut lining, restore healthy bacteria

7. Nutrient Deficiencies

You can eat plenty of food and still be deficient in key micronutrients. Common fatigue-related deficiencies include:

Vitamin B12
Vitamin D
Magnesium
Folate
CoQ10

➡️ Testing matters: Standard blood panels often miss functional deficiencies
➡️ How to correct: Tailored supplementation, methylated B vitamins, nutrient-dense whole foods

8. Chronic Infections or Reactivated Viruses

Some people feel drained because of underlying infections like Epstein-Barr virus (EBV), Lyme disease, or chronic mold exposure. These can activate the immune system 24/7, leaving you feeling chronically inflamed and depleted.

➡️ Clues: Fatigue that comes in waves, swollen lymph nodes, headaches, joint pain
➡️ Functional tools: Immune support, antiviral herbs, mold detox, and inflammation regulation

9. Hormonal Imbalance

For both men and women, unbalanced hormones can severely affect energy. Low testosterone, estrogen dominance, or perimenopausal shifts can result in fatigue, mood swings, low libido, and poor exercise recovery.

➡️ Testing to consider: Total and free testosterone, estradiol, progesterone, DHEA
➡️ Support options: Bioidentical hormones, herbal support, lifestyle, and stress reduction

10. Toxin Overload

We are exposed to thousands of toxins daily—from pesticides and plastics to mold and heavy metals. If your detox pathways are sluggish, these substances accumulate and contribute to fatigue, brain fog, and hormonal disruption.

➡️ What to evaluate: Mold exposure, heavy metal testing, liver function
➡️ Supportive strategies: Glutathione, binders, sauna therapy, liver-supportive foods like cruciferous vegetables

When to Seek Help

If you’ve tried getting more sleep, reducing caffeine, and improving your diet but still feel chronically tired, it’s time to look deeper.

Functional medicine offers a root-cause approach to fatigue by:

Running advanced labs
Looking at multiple systems together (thyroid, gut, hormones, adrenals)
Creating a personalized plan that supports long-term energy production—not just symptom relief

Final Thoughts: You’re Not Just “Lazy”—There’s a Reason You’re Tired

Chronic fatigue is a biological signal, not a character flaw. If you're constantly asking, "Why am I always tired?", your body may be trying to tell you something deeper is going on.

Don’t settle for “normal labs” or generic advice. With a personalized, functional medicine approach, you can uncover the real cause of your fatigue—and finally reclaim your energy and vitality.

Ready to find out why you're so tired?
At Sheen Vein and Cosmetics, our functional medicine team uses advanced diagnostics to uncover the root cause of fatigue and develop a personalized plan for sustainable energy and whole-body wellness.

📞 Book your consultation today and start feeling like yourself again.

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