The conventional view of cholesterol holds that lower numbers are better. High LDL cholesterol is treated as a disease state to be corrected through statins or dietary intervention. The assumption is that cholesterol in the bloodstream is essentially a problem — a marker of cardiovascular risk, a substance that accumulates as plaque, a value that medicine should drive downward. The clinical results of this approach over four decades have been mixed in ways that the conventional framing struggles to explain. A different reading is possible. Cholesterol and Jing (정) — the classical Korean medical concept of stored essence — describe many of the same functional roles in human physiology. The convergence is striking enough that the question becomes worth asking directly: is what modern medicine calls cholesterol substantially what classical Korean medicine has been calling Jing for two thousand years?
In Summary
- Jing (정) in classical Korean Traditional Medicine (KTM) is the body’s stored essence — the highly concentrated form in which surplus energy is held for high-priority biological work.
- Cholesterol functions in modern physiology as the substrate for cell membrane integrity, steroid hormone synthesis (cortisol, sex hormones, vitamin D), neural tissue, and the bile acids that enable fat absorption.
- The functional overlap is substantial: both Jing and cholesterol are biological reserves used for high-priority work, both decline with age, both correlate with vitality, and both are depleted by chronic illness.
- Modern research showing that aggressive cholesterol lowering does not reduce mortality in many patient populations is consistent with the classical position that depleting Jing-like reserves causes harm even when the reserves look elevated by some metrics.
- The cholesterol-as-Jing hypothesis does not claim cholesterol equals Jing — Jing is a broader concept — but it suggests that what statins lower may include reserves the body genuinely needs for high-priority biological function.
The Functional Profile of Jing
Classical KTM describes Jing as the body’s most concentrated and refined storage form of biological substance. The kidney is its primary storage organ, but Jing is used throughout the body for biological work that requires high-quality substrate. The classical text lists the functions of Jing in a specific order that is clinically informative.
Jing is the substrate for growth and development. Children grow because they have abundant Jing; growth slows as Jing accumulation slows in early adulthood. Jing is the substrate for reproductive function. Sexual maturity correlates with Jing accumulation; reproductive decline correlates with Jing depletion. Jing is the substrate for brain and nervous system function. The classical phrase 정생수 (Jing produces marrow), where marrow includes both bone marrow and the substance of the brain and spinal cord, describes this relationship. Jing is the substrate for sustained immune function. Patients with depleted Jing show characteristic patterns of immune fragility — frequent illnesses, slow recovery, vulnerability to infections that healthier patients shrug off.
What is striking about this list is how specifically it overlaps with the functions modern biochemistry assigns to cholesterol. Cholesterol is essential for cell membrane integrity throughout the body. It is the precursor for all steroid hormones — cortisol, the sex hormones, vitamin D, the bile acids. It is concentrated heavily in the brain, where it constitutes roughly 20% of the dry weight of brain tissue. It is consumed in the synthesis of every new cell and replaced from circulating reserves. The biological work that classical KTM assigns to Jing maps with remarkable precision onto the biological work that modern biochemistry assigns to cholesterol.
What Cholesterol Actually Does
Modern medical education tends to emphasize cholesterol’s role in cardiovascular disease, which gives the substance a misleadingly narrow profile in many clinicians’ minds. The actual biochemistry is broader. Cholesterol synthesis happens in nearly every cell of the body — the liver produces a substantial fraction, but cells throughout the body produce their own cholesterol when they need it. The reason for this distributed production is that cholesterol is required everywhere.
Cell membranes consist of phospholipids stabilized by cholesterol. Without adequate cholesterol, membranes become unstable, permeable in ways they should not be, and unable to maintain the gradient relationships that cellular metabolism depends on. The integrity of every cell in the body depends on adequate cholesterol availability.
Steroid hormones — cortisol from the adrenal cortex, testosterone and estrogen from the gonads, vitamin D synthesized in the skin — are all built from cholesterol. The body cannot produce these hormones from any other substrate. Cortisol regulates the body’s response to stress; the sex hormones regulate reproductive function and many secondary metabolic patterns; vitamin D regulates calcium metabolism and immune function. Each of these systems depends on cholesterol availability.
Bile acids, synthesized from cholesterol in the liver, enable the digestion and absorption of dietary fats. Without adequate bile acid production, fat-soluble vitamins (A, D, E, K) cannot be absorbed, and the body experiences cumulative deficiencies that present as immune, neurological, and skin problems whose root cause in inadequate bile acid synthesis is rarely identified.
The brain contains roughly 20% of the body’s total cholesterol. Myelin sheaths around nerve fibers are cholesterol-rich. Synaptic function depends on cholesterol in the membranes at the synapse. Cognitive function over the lifespan correlates with brain cholesterol availability, and several lines of research have linked aggressive cholesterol lowering to subtle cognitive decline that the medical literature has been slow to acknowledge.
This is what cholesterol actually does in the body. The cardiovascular plaque story, when laid alongside this broader picture, looks more like one possible failure mode of a substrate the body depends on for many critical functions, rather than the primary identity of that substrate.
Why the Jing-Cholesterol Overlap Is Worth Taking Seriously
The convergence between Jing and cholesterol becomes interesting at the level of specific functional predictions. Both Jing and cholesterol decline measurably with age. Both are higher in younger and healthier patients. Both show characteristic patterns of depletion in chronic illness. Both are required for high-priority biological work that the body prioritizes when reserves are limited.
The classical KTM prediction is that depleting Jing causes broad systemic decline because Jing is the substrate for the body’s most important work. The cholesterol-as-Jing hypothesis predicts the same thing in modern biochemical vocabulary: depleting cholesterol below the level required for the body’s broader functions should produce systemic decline even if the cardiovascular plaque metric improves.
This is, broadly, what the cholesterol-lowering literature actually shows. Statin trials demonstrate clear benefit in narrow populations — patients with established cardiovascular disease, men in their middle years with multiple risk factors. They show much less benefit, and sometimes net harm, in broader populations — women, elderly patients without prior cardiovascular events, primary prevention in low-risk populations. The benefits track patients in whom the cardiovascular plaque pathway is the dominant clinical risk; the harms appear in patients whose other cholesterol-dependent functions are compromised by lowering.
This is exactly what the Jing framework would predict. Jing depletion that occurs as a side effect of treating a specific local problem (in this case, cardiovascular plaque) produces broader systemic harm because Jing supports many functions, not just one. The statin literature is reading the same pattern from a different vocabulary.
The Steven Sinatra Findings and the Plaque Disconnect
A finding from the cardiology literature that is worth pausing on: aggressive cholesterol lowering through statins does not reliably reduce vascular plaque. A 2003 study published in the Journal of the American College of Cardiology followed patients on statin therapy and measured their plaque progression with electron beam tomography. Cholesterol levels fell as expected. Plaque levels did not. Both treatment groups in the study showed approximately 9.2% plaque progression over the follow-up period despite substantial cholesterol reduction.
This finding has been replicated in various forms. The “LDL is bad” hypothesis predicts that lowering LDL should reduce plaque; the actual data does not support this prediction cleanly. The disconnect is consistent with the view that cholesterol’s role in plaque formation is more complicated than the simple deposition model assumes. Plaque appears to form primarily through oxidative and glycemic damage to the vascular endothelium, with cholesterol participating as part of the repair response rather than as the initiating insult.
In this reading, lowering cholesterol does not address the actual cause of plaque (endothelial damage from oxidation and glycation) and does deplete the substrate the body needs for membrane integrity, hormone synthesis, brain function, and bile production. The cardiovascular intervention is being purchased at a cost to other systems whose long-term consequences are difficult to measure but increasingly documented in the cognitive decline, hormonal disruption, and chronic fatigue patterns that statin-treated patients sometimes develop.
Classical Korean medicine, if asked to comment, would describe this as treating a downstream symptom by depleting upstream Jing. The cardiovascular plaque is the symptom; the cholesterol is part of the upstream reserve the body uses to handle many forms of biological work. Depleting the reserve to manage one of the symptoms is a clinical decision that should be made with eyes open to the broader cost, and current practice has been slow to acknowledge what that cost actually is.
Why Cholesterol Behaves Like a Reserve Rather Than a Toxin
A useful exercise in seeing the cholesterol-as-Jing hypothesis clearly is to ask: how would the body’s handling of cholesterol look if cholesterol were genuinely a biological reserve? It would be synthesized by many cells throughout the body, indicating its essential nature. It would be tightly regulated through homeostatic feedback, with the body adjusting production based on demand. It would increase in periods of biological stress, because the body would mobilize reserves to handle the stress. It would decline gracefully with age, in patterns that correlate with overall vitality. It would be implicated in many bodily systems rather than just one.
This is precisely how cholesterol behaves. The synthesis is distributed across every cell. The regulation is homeostatic — if dietary intake is high, the body produces less; if intake is low, the body produces more. Cholesterol increases during stress, which conventional medicine often treats as a problem but which from the reserve-mobilization perspective is exactly what should happen. The age-related decline pattern matches Jing patterns. The implication in many systems matches Jing’s broad functional profile.
The behavior of cholesterol in the body is the behavior of a reserve, not a toxin. The conventional framing treats it as a problematic accumulation to be managed downward; the reserve framing treats it as a critical substrate to be maintained at adequate levels. The clinical implications of these framings are different. Treating cholesterol as a toxin leads to aggressive lowering as the default approach. Treating cholesterol as a reserve leads to targeted intervention only in patients whose plaque pathway is the dominant clinical concern, with attention to maintaining adequate cholesterol for the body’s other needs.
Where the Hypothesis Stops
The cholesterol-as-Jing hypothesis is suggestive but should not be overstated. Jing in classical KTM is a broader concept than cholesterol; it includes aspects of reproductive function, marrow production, immune capacity, and developmental reserve that cholesterol alone does not capture. The kidney’s Jing storage includes substrates and signaling molecules beyond cholesterol. Cholesterol is one substrate that functions like Jing in many respects, not a complete biochemical implementation of the classical concept.
The hypothesis is also speculative in the sense that the classical Korean physicians who developed the Jing concept did not have biochemical tools to identify specific substrates. They observed the functional pattern — biological reserve that supports high-priority work — and named it Jing. The convergence with cholesterol is a modern observation about how the classical functional category and a specific modern biochemical category overlap. It is not a claim that classical physicians knew about cholesterol or that cholesterol exhausts the Jing concept.
What the hypothesis does is provide a useful framework for understanding why aggressive cholesterol lowering has produced disappointing clinical results in many patient populations. The classical Korean medical view that depleting a critical reserve to manage one downstream symptom causes broader harm is consistent with the actual clinical data. The framework is heuristic rather than definitive, but it generates predictions that match observation in ways the simple “cholesterol is bad” model does not.
In my clinical experience, patients who learn about the cholesterol-as-Jing framework change their relationship with their lipid numbers in productive ways. They stop treating any elevation as automatically pathological. They become more interested in why their body is producing more cholesterol (often a stress or inflammatory response) than in simply driving the number down. They engage with cholesterol-lowering medications more thoughtfully, asking whether their specific clinical situation justifies the broader systemic cost. This shift in framing produces better clinical decisions on average than the conventional “lower is better” approach.
Summary
Classical Korean medicine describes Jing (정) as the body’s stored essence — the concentrated reserve used for high-priority biological work including growth, reproduction, brain function, and immune capacity. Modern biochemistry assigns essentially the same functional profile to cholesterol: cell membrane integrity, steroid hormone synthesis, neural tissue, and bile production. The functional overlap between Jing and cholesterol is striking enough to suggest that what classical Korean medicine has been calling Jing for two thousand years includes substantially what modern medicine measures as cholesterol. Cholesterol behaves like a reserve rather than a toxin — distributed synthesis, homeostatic regulation, stress mobilization, age-related decline correlating with vitality. The clinical literature showing that aggressive cholesterol lowering does not reliably reduce plaque and produces broader systemic harms in many populations is consistent with the Jing framework’s prediction that depleting a critical reserve to manage one downstream symptom causes broader harm. The hypothesis is heuristic rather than definitive — Jing is a broader concept than cholesterol — but it generates predictions that match observation better than the simple “cholesterol is bad” model.
Related: Jing and the Theory of Surplus · Constitutional Medicine and Precision Medicine
