The Drive with Peter Attia — Robert Sapolsky

On: The pervasive effect of stress – is it killing you?

Episode: 51

Date: April 2019

Background: Neuroendocrinologist.

Key Subjects:

  • Dual hormonal pathway triggered by stress stimulus:
    • Immediate response – adrenalin:
      • Triggers activation of parasympathetic nervous system.
    • Secondary response – cortisol:
      • Continues parasympathetic response (elevated blood glucose).
      • Shuts down digestion, metabolism, growth hormones, reproduction.
      • See also (“The Hour Between Dog and Wolf“)
  • Narrow window of optimum level of cortisol, depends on:
    • How much is released (too much or too little not good).
    • How responsive you are to certain levels (type of receptors; individual biological set-points).
  • Correlation between (perception of) social status and stress:
    • Humans play roles in multiple hierarchies (work, family, hobbies).
    • Typically, where they rank highest is the most meaningful to them.
  • Correlation between personality and stress:
    • Regardless of rank, combination of genetics and environment influences how you perceive certain potential stress stimuli.
    • Can be seen in size and activity of amygdala.
  • Three brain systems:
    • Brain stem: autonomic system (breathing, body regulation).
    • Limbic system: emotions, survival activities (food, sex) (amygdala, hippocampus, thalamus).
    • Cortex: executive function, thinking, reasoning, planning.
  • “Optimal” levels of stress stimulate:
    • Delivery of energy, oxygen, synapses, memory retention.
  • Relationship between (mental) health and income:
    • Level of income explains large part of variability in health.
      • Not necessarily or only due to lower access to health care for poor.
      • Subjective view of socio-economic status is at least as good a predictor of health as income.
    • Not necessarily about being poor (only), but feeling poor.
      • What makes you feel poor: awareness of inequality.
    • What makes you aware of inequality.
      • Constant reminders in (social) media.
    • Current (media) environment has potential to amplify difference.
      • Causing wider spread chronic stress.
  • Chronic stress:
    • Strengthens (grows) the amygdala (fear, anxiety, aggression).
    • Weakens (shrinks) the hippocampus (memory).
    • Weakens the frontal cortex (impulse control, long-term planning, empathy).
  • Fixes for chronic stress:
    • Whatever you do (exercise, meditation), do it regularly rather than one-offs.
  • Genetic basis for stress, depression:
    • Direct linkages between genes and depression unclear.
      • Similar to other complex behavior.
    • Likely that certain genes make you more vulnerable to how you react to external stimuli.
  • Stress and sleep (see “Sleep“):
    • Cortisol spikes about one hour before sleep.
    • Cortisol inhibits release of melatonin.
      • More difficult to fall asleep, less brain restoration.
    • Chronic stress causes cortisol to stay high throughout.
      • Lower sleep quality.


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