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Environmental discontinuity hypothesis: Buffer dysfunctions as a source of human disease
1Radiology, Stanford University, 470 University Avenue, Palo Alto, CA 94301, USA. ayun@stanford.edu
Medical Hypotheses
|June 9, 2006
Summary
Modern environmental changes create discontinuous exposures, potentially leading to physiological buffer dysfunction and increased disease risk. This includes issues with skin pigmentation, temperature, and altitude, impacting health outcomes like melanoma.
Area of Science:
- Human physiology
- Environmental adaptation
- Evolutionary medicine
Background:
- Organisms rely on adaptive physiologic buffers for environmental plasticity.
- Modern human environments exhibit increased environmental discontinuity (e.g., sunlight, temperature, altitude).
- This discontinuity may represent a Darwinian maladaptation, potentially inducing buffer dysfunction and disease.
Purpose of the Study:
- To propose environmental discontinuity as a driver of disease.
- To examine the role of skin pigmentation as a buffer against discontinuous sunlight exposure.
- To explore the links between environmental discontinuity and various health conditions.
Main Methods:
- Conceptual analysis of environmental discontinuity and physiological buffers.
- Review of existing literature on sunlight exposure, skin pigmentation, and associated health outcomes.
- Discussion of potential impacts of discontinuous temperature and pressure variations.
Main Results:
- Environmental discontinuity may lead to skin pigmentation buffer dysfunction, increasing risks for conditions like melanoma.
- Sun-avoidance campaigns, while intended to protect, may disrupt beneficial sun-dependent pathways (e.g., vitamin D, melatonin).
- Discontinuous temperature and pressure variations are implicated in conditions such as viral infections, heart failure, and autonomic dysfunction.
Conclusions:
- Environmental discontinuity is a significant factor in modern human health, contributing to disease.
- Re-evaluating human-environment interactions and adaptive buffers is crucial for public health.
- Understanding these mechanisms may inform therapeutic strategies to mitigate risks associated with environmental changes.
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