Why Am I So Tired All the Time? Root Causes a Functional Medicine Doctor Looks For

"Why am I so tired all the time?" is one of the most frequent questions I hear in my Stamford, CT functional medicine practice. If you're getting a full night's sleep and still dragging through the day, something deeper is likely going on.

Fatigue Is a Symptom, Not a Diagnosis

Chronic fatigue isn't a single condition; it's a signal that something in the body isn't functioning optimally. Conventional medicine often screens for the obvious causes, but many underlying contributors can be missed in a standard visit.

Common Root Causes of Chronic Fatigue

Thyroid dysfunction, including subclinical hypothyroidism that doesn't always show up on basic screening, is a frequent culprit. Blood sugar imbalances, whether from insulin resistance or reactive hypoglycemia, can cause energy crashes throughout the day. Nutrient deficiencies, particularly in iron, B12, vitamin D, and magnesium, are surprisingly common. Poor gut health can impair nutrient absorption and drive systemic inflammation, while chronic stress and adrenal dysregulation can throw off the body's natural cortisol rhythm. Sleep quality issues, such as undiagnosed sleep apnea, and low-grade chronic infections can also quietly drain energy.

How Functional Medicine Testing Finds the Answer

Instead of stopping at "your labs are normal," a functional medicine approach digs deeper with comprehensive testing, including full thyroid panels (not just TSH), micronutrient testing, blood sugar and insulin markers, cortisol patterns, and gut health assessments. This more complete picture often reveals exactly why energy has been so hard to come by.

Getting Your Energy Back

Once the root cause (or, more often, combination of causes) is identified, a personalized plan can address it directly, whether that means correcting a nutrient deficiency, rebalancing blood sugar, supporting thyroid function, or healing the gut. Many patients are surprised at how much better they feel once the real issue is treated rather than just managed.

If chronic fatigue has become your "normal" and you're ready to figure out why, Dr. Lisa Gengo works with patients throughout Stamford, Greenwich, Darien, New Canaan, and Fairfield County to find real answers. Book a discovery consult to get started.

Disclaimer: This content is for informational purposes only and is not a substitute for professional medical advice.

Curious to Learn More? Check out our blog on Bloating After Eating? A Functional Medicine Guide to Gut Health.