The Four Constraints Your Diet Cannot Escape

If you are exhausted by modern diet advice, your skepticism is rational. The usual arguments are built on weak inputs and endless interpretation.


This episode takes a different route. It starts with what cannot be negotiated, then checks the historical record that cannot misremember.


You will hear four constraints that narrow the human diet before you ever talk about preferences:


The protein ceiling: why too much lean protein becomes a real physiological limit, and why fat was not optional for hunter-gatherers


Essential nutrients: what “essential” means biochemically, and why there is no essential dietary carbohydrate requirement


Energy density and survival logic: why fat’s calorie density changes the risk equation in the wild


The metabolic switch: why running on fat and ketones is not a gimmick, and what it implies about the default human fuel pattern


Then the episode checks that model against hard evidence: stable isotope analysis and trophic level signatures preserved in bone collagen. The pattern is consistent. For long stretches of human history, the signature looks like high trophic-level feeding, and the major break comes with agriculture.


Finally, it brings the model into the modern context: why high-fat plus high-carb eating creates “metabolic incoherence,” and why personal calibration still matters through genetics, microbiome differences, and a real adaptation window.


Next episode: The constraints become a practical tool. We move from population-level boundaries to personal calibration, and apply the model to modern diet camps to see what holds up.


Derived from Mark’s essay: What Humans Can Actually Eat | Part II (https://www.healthundercontrol.com/p/...)


More audio and essays at Mark’s Substack: HealthUnderControl.com (https://healthundercontrol.com/)


Mark’s practice (the HUC philosophy in action): Unblocked.Health (https://unblocked.health/)





Subscribe for constraint-based nutrition you can verify in your own body, without diet tribalism or recycled certainty.








This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit www.healthundercontrol.com (https://www.healthundercontrol.com?ut...)