Adapted to flee famine: adding an evolutionary perspective on anorexia nervosa

Area of Science:

• Evolutionary biology
• Neuroscience
• Psychiatry

Background:

• Current anorexia nervosa (AN) theories, including psychological, societal, and biological factors, are incomplete.
• Existing models fail to fully explain the disorder's phenomenology and neuroendocrine findings.

Purpose of the Study:

• To propose and provide evidence for an evolutionary hypothesis of anorexia nervosa.
• To explain AN symptoms as evolved adaptive mechanisms.

Main Methods:

• Review of existing research on AN phenomenology, neuroendocrine dysfunction, and evolutionary biology.
• Analysis of AN symptoms (food restriction, denial of starvation, hyperactivity) through an evolutionary lens.

Main Results:

• Anorexia nervosa symptoms may represent archaic adaptations for survival in resource-scarce environments.
• This hypothesis accounts for AN-like syndromes in humans and animals.
• The evolutionary model aligns with observed physiological, cognitive, and behavioral changes in AN patients.

Conclusions:

• Anorexia nervosa may be rooted in evolved adaptive mechanisms, not solely psychological or biological defects.
• This evolutionary perspective offers a more comprehensive understanding of AN.
• Further research is warranted to explore the genetic and physiological underpinnings of these proposed adaptations.