I just want to feel like myself again.
“I Know It’s My Testosterone.”
He arrived with a clear conclusion.
At 48 years old, he was experiencing persistent fatigue, mental fog, and a growing sense that his body was no longer keeping up with his life. Like many patients today, he had done his research. He spoke fluently in lab values, trends, and treatment options.
“I know it’s my testosterone,” he said.
“That’s why I feel this way.”
His total testosterone level sat toward the lower end of the laboratory reference range—technically normal, but not robust. In isolation, the number seemed to support his framing. The symptoms aligned closely enough to make the conclusion feel reasonable.
And this is where modern medicine often pauses—or prematurely concludes.
When “Normal” Isn’t Neutral
Initial evaluation did not reveal a glaring abnormality. Testosterone was not frankly deficient. Other screening labs appeared unremarkable. Even his vitamin B12 level fell within the laboratory’s defined “normal” range—though just barely.
But laboratory reference ranges are built for populations, not individuals.
They define what is statistically common, not what is biologically sufficient for a given person, at a given moment, under a given set of metabolic demands.
Serum vitamin B12, in particular, is an imperfect marker. It reflects circulating levels rather than functional intracellular availability, where B12 is required for DNA synthesis, neurologic integrity, and red blood cell production. As described in clinical reviews, patients may experience functional deficiency even when serum values fall within the lower end of the reference range.¹ A “low-normal” value may be sufficient for one individual and inadequate for another, depending on metabolic demand, absorption, and utilization.
In this case, it was insufficient.
When Stimulation Outpaces Support
Following initiation of therapy, his clinical response did not align with the expected outcome. Rather than improved energy, he reported increased irritability and persistent fatigue.
In regenerative and systems-based medicine, such responses prompt reassessment—not because a therapy is inherently problematic, but because physiologic systems respond differently depending on underlying support. Further evaluation revealed evidence of impaired red blood cell production and marginal nutrient reserves that had not been clinically apparent at baseline.
In this context, hormonal signaling appeared to exceed the body’s available metabolic resources. What emerged was not a complication of therapy, but a signal that foundational support required attention before further optimization could occur.
This is a critical distinction in regenerative medicine.
Regeneration Requires Substrate, Not Just Signals
Hormones do not create energy.
They direct it.
For regeneration to occur—whether through hormones, peptides, or other biologic therapies—the body must have the raw materials necessary for cellular repair. When those materials are absent or marginal, stimulation alone can destabilize the system.
Fatigue, in this context, was not a hormonal failure.
It was a metabolic message.
One the body had been sending quietly all along.
Listening Beneath Certainty
Patients rarely arrive speaking in physiology. They arrive speaking in interpretations—shaped by experience, research, and the understandable desire for clarity.
The role of regenerative medicine is not to reject those interpretations, but to listen beneath them.
To ask:
What does this body lack?
What conditions are preventing repair?
What appears “normal” on paper but insufficient in practice?
In this case, addressing foundational nutrient support changed the trajectory. Energy stabilized. Mood improved. The body became responsive again—not because more was added, but because what was missing was restored.
Healing From Within Begins with the Ground
This case illustrates a central principle that will echo throughout Healing from Within:
Regeneration does not begin with optimization.
It begins with restoration.
Before we stimulate, we must support.
Before we amplify signals, we must ensure the system can respond.
Because healing rarely fails from lack of intervention.
It fails when we mistake normal for enough.
Interested in a more individualized approach to hormone health?
At Mercure, hormone optimization begins with a comprehensive evaluation—looking beyond single lab values to understand nutrient status, metabolic health, and the conditions required for your body to respond safely and effectively.
Learn more about our approach to hormone optimization
Clinical reference:
¹ Stabler SP. Vitamin B12 Deficiency. N Engl J Med. 2013.
Langan RC, Goodbred AJ. Vitamin B12 Deficiency: Recognition and Management. Am Fam Physician. 2017.
Clinical details have been generalized to preserve patient privacy and illustrate broader principles rather than individual outcomes.
