Modern WisdomHow Catching Covid Can Change Your Personality - Dr Diana Fleischman | Modern Wisdom Podcast 290
CHAPTERS
- 0:00 – 0:26
Post-COVID social anxiety and the question: can illness change personality?
Diana opens by describing a brief post-COVID period where she felt unusually socially anxious and wary of strangers. Chris frames the central topic: what it even means for a virus to “change your personality.”
- •Personal anecdote: heightened social anxiety after COVID despite no longer being infectious
- •Defining the core question: personality change vs temporary state change
- •Setting the stage for an evolutionary psychology lens on sickness behavior
- 0:26 – 1:37
Pathogens vs hosts: behavior manipulation, inflammation, and shifting priorities
They explore evidence that viruses/bacteria can influence host behavior to aid transmission, while the host’s own evolved priorities also shift during infection. Diana links COVID’s inflammation and immune signaling to broad changes in behavior and personality-relevant traits.
- •Pathogens may benefit from host behavior changes that increase spread
- •Hosts reallocate goals when sick (less novelty-seeking, more safety/withdrawal)
- •Inflammation as a signal that drives “behave as if infected” responses
- •COVID’s cytokine storm/long-hauler inflammation as a candidate mechanism
- 1:37 – 3:43
Aligned and misaligned incentives: sneezing, fever, and appetite suppression
Chris and Diana discuss how some sickness behaviors help both host and pathogen (e.g., sneezing), while others are host defenses (e.g., fever). Diana argues that common responses like appetite loss can be protective and energy-conserving.
- •Sneezing can clear irritants but also spreads pathogens
- •Fever as a host-favorable adaptation; critique of routine fever-reducers
- •Reduced appetite conserves energy for immune function
- •If pathogens could fully manipulate us, they’d likely increase hunger
- 3:43 – 6:45
Lassitude: the ‘emotion of being sick’ and social sensitivity under immune activation
Diana introduces ‘lassitude’ as a coordinated emotional/physiological state optimized for recovery and eliciting care. They cover experiments (endotoxin) showing increased rejection sensitivity and emotional reactivity during immune activation.
- •Lassitude as an evolved state: fatigue, chills, pain sensitivity, emotional sensitivity
- •Emotions as adaptive programs for solving recurrent problems (anger, fear, etc.)
- •Endotoxin studies: higher social rejection sensitivity under immune activation
- •Rejection-task example shows how minimal exclusion can feel impactful
- 6:45 – 9:30
Why sick people crave comfort foods: safety, energy costs, and ‘food preference crystallization’
They unpack why illness drives a preference for familiar, simple foods and sometimes not eating at all. Diana connects this to pathogen avoidance, digestion costs, and childhood periods where “safe foods” are learned.
- •Digestion costs meaningful resting energy; illness reallocates resources
- •Novel foods carry higher pathogen risk; preference shifts to “known safe” foods
- •Comfort-food narrative may mask a safety/avoidance function
- •Childhood ‘crystallization’ of food preferences as local adaptation
- 9:30 – 14:36
Needy when sick: signaling vulnerability, avoiding strangers, and relationship strain
Diana explains why sickness increases dependence on familiar allies and reduces openness to new social contact. They discuss signaling vulnerability to elicit caregiving and how chronic illness/inflammation can change relationship dynamics.
- •Humans evolved to rely on kin/friends during vulnerability
- •Sickness reduces extraversion/novel social effort; increases investment in existing ties
- •Animal studies: “acting sick” can be strategically suppressed around rivals
- •Marriage vows imply tolerance for personality changes in illness
- 14:36 – 17:17
Faking sickness and social enforcement: costly signals and harsh ‘cures’ as deterrents
The conversation turns to deception—how people may exaggerate vulnerability to avoid costs. Diana describes how societies historically made faking expensive via unpleasant treatments, functioning as a credibility filter.
- •‘Man flu’ and self-deception: hard to gauge exaggeration
- •Battlefield avoidance as a context where faking is adaptive
- •Historical cures (leeches, trepanning, mercury) as deterrents to malingering
- •Modern vulnerability displays are cheaper, changing social skepticism
- 17:17 – 19:33
Pathogen load and culture: conservatism, conformity, and taboo logic
They discuss controversial research linking higher pathogen prevalence to greater cultural conservatism and conformity. The idea is that tradition can function as a low-risk, “already tested” behavioral package under high disease threat.
- •Randy Thornhill’s pathogen-load hypothesis and its controversies
- •Conformity/tradition as risk-reduction under disease pressure
- •Food taboos (e.g., pork) as potentially pathogen-related norms
- •COVID highlights differences in how societies weigh risk, death, and tradeoffs
- 19:33 – 24:59
From zoonoses to factory farming: pandemics, ‘clean meat,’ and practical ethics
Diana argues that animal agriculture increases pandemic risk and that cultivated (“clean”) meat may be a realistic solution. Chris shares how animal-rights arguments shifted his behavior, and Diana emphasizes harm-reduction over purity.
- •Zoonotic pathways and the amplification risks of animal markets/factory farms
- •Clean/cultivated meat as a pragmatic path (and branding matters)
- •Disillusionment with vegan movement growth; importance of incremental change
- •‘Practical veganism’: different foods imply different suffering footprints
- 24:59 – 32:49
Nature, hypocrisy, and cheap moral emotions: scandal and virtue signaling
They broaden into moral psychology: why people enjoy scandal and low-cost moral posturing. Diana notes the evolutionary logic of hypocrisy—condemning others while preserving one’s own behavior.
- •‘Nature as a suffering cesspool’ complicates simplistic eco-morality
- •Scandal as low-effort moral satisfaction
- •Cheap-talk vs costly virtue signaling
- •People systematically see themselves as more moral; anti-vegan backlash as status move
- 32:49 – 36:49
Long COVID, inflammation, and persistent personality shifts: smoke detector principle
Chris asks why illness effects would last beyond recovery. Diana describes long-hauler inflammation, links between inflammation and depression/anxiety, and uses the smoke detector principle to explain why bodies may ‘overreact’ for safety.
- •Long COVID: lingering inflammatory markers and ongoing sickness behavior
- •Inflammation as a pathway to mood and cognition changes (brain fog, sensitivity)
- •Obesity as chronic systemic inflammation that can mimic infection signals
- •Smoke detector principle: false alarms are cheaper than misses
- 36:49 – 51:59
Sex, libido, and mating under disease threat: sex differences and life history strategies
They explore how infection risk reshapes mating dynamics, with women generally more sensitive to pathogen threat and libido suppression. Diana introduces life history theory (fast vs slow strategies) to predict divergent responses to mortality cues.
- •Libido typically drops under illness; sex differences in suppression
- •Women’s higher infection sensitivity given pregnancy/offspring costs
- •Life history theory: threats can push caution (slow) or urgency (fast)
- •Early hardship cues can accelerate puberty timing and shift strategies
- 51:59 – 57:20
Asexuality, hormones, and modern dualism: resisting biological explanations
Diana discusses debates over asexuality (orientation vs condition) and argues many identity labels may describe normal variation. She emphasizes hormonal influences (e.g., testosterone effects) and critiques cultural discomfort with embodiment.
- •Asexuality debate: orientation vs dysfunction; overlap with health and hormones
- •Testosterone can change libido in some trans individuals, suggesting biological drivers
- •‘Demisexual’ lexicon as potentially normal female-typical mating selectivity
- •Modern dualism: people accept psychological narratives but reject biological causation
- 57:20 – 1:01:26
Predictability, ‘counter-control,’ and the future of behavioral inference from faces and data
They examine why people dislike being predictable: it implies control by others. Diana cites counter-control and argues that AI/governments may infer traits (sex, orientation cues, generosity, psychopathy risk) from faces and behavior—raising discomfort and political tension.
- •Counter-control: aversion to being predictable/controllable
- •Personality inventories predict sex at high accuracy (as claimed)
- •Emerging ‘new phrenology’: trait inference from faces and micro-behavior
- •Public fear rises when traits feel immutable and actionable by institutions
- 1:01:26 – 1:09:37
Evolutionary psychology as self-knowledge: meditation, rumination, and seeing the ‘source code’
Chris and Diana close by reflecting on evo psych as a framework for understanding motivations and mindfulness experiences. Diana shares retreat experiences and how explanatory frames can make inner noise more intelligible—though not fully escapable.
- •Evo psych reframes mindfulness: not just observing thoughts, but understanding why
- •Retreat rumination examples show persistent evolved concerns (status, jealousy, conflict)
- •Self-insight can be clarifying but also cynicism-inducing
- •Wrap-up: where to find Diana’s work and episode close
