{
  "title": "The cost of the endless feed",
  "author": "FLDI Research",
  "version": "1.1",
  "checkedThrough": "9 November 2026",
  "note": "Editorial argument and critical evidence review, not a registered systematic review or new causal estimate. The historical superlative is an editorial position, not a scientific ranking. The article has one lifetime calculator and fixed supporting figures; global audience, dose and valuations are assumptions. Additional formulas are supplemental.",
  "units": {
    "daysPerYear": 365.25,
    "minutesPerDay": 1440,
    "fixedWakingHours": 16,
    "lifetimeAgeEndExclusive": true,
    "currency": "illustrative constant USD, no PPP adjustment"
  },
  "scenarioPresets": {
    "Low": {
      "audienceBillions": 1,
      "minutes": 30,
      "gap": 0.05
    },
    "Central": {
      "audienceBillions": 1.5,
      "minutes": 60,
      "gap": 0.2
    },
    "High": {
      "audienceBillions": 2,
      "minutes": 90,
      "gap": 0.5
    },
    "Net benefit": {
      "audienceBillions": 1.5,
      "minutes": 60,
      "gap": -0.1
    }
  },
  "sources": [
    {
      "id": 1,
      "authors": "Ofcom",
      "title": "Online Nation 2025",
      "year": 2025,
      "venue": "UK communications regulator; Figures 22, 24 and 77",
      "url": "https://www.ofcom.org.uk/siteassets/resources/documents/research-and-data/online-research/online-nation/2025/online-nations-report-2025.pdf?v=409837",
      "type": "Measurement",
      "scope": "UK app and website use; whole platforms, not Reels or Shorts separately."
    },
    {
      "id": 2,
      "authors": "Qustodio",
      "title": "Lost in the Scroll: Annual Data Report 2025",
      "year": 2026,
      "venue": "Original family device telemetry; social media section, p. 43",
      "url": "https://static.qustodio.com/public-site/uploads/2026/01/15090129/ADR_2025_EN-2.pdf",
      "type": "Measurement",
      "scope": "Children aged 4–18 in monitored families; commercially collected, nonrepresentative sample."
    },
    {
      "id": 3,
      "authors": "Nguyen et al.",
      "title": "Feeds, feelings, and focus: A systematic review and meta-analysis examining the cognitive and mental health correlates of short-form video use",
      "year": 2025,
      "venue": "Psychological Bulletin 151:1125–1146; doi:10.1037/bul0000498",
      "url": "https://pubmed.ncbi.nlm.nih.gov/41231585/",
      "type": "Research",
      "scope": "71 studies; 98,299 participants; pooled associations across short-form video platforms."
    },
    {
      "id": 4,
      "authors": "Tang et al.",
      "title": "Association Between Short-Form Video Use and Mental Health: Systematic Review and Meta-Analysis",
      "year": 2026,
      "venue": "Journal of Medical Internet Research 28:e82503; doi:10.2196/82503",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12998613/",
      "type": "Research",
      "scope": "58 included studies; 53 pooled; 96,676 participants overall. Baseline correlations, not treatment effects."
    },
    {
      "id": 5,
      "authors": "Arouch et al.",
      "title": "Short-form video, cognitive and mental health outcomes: a systematic review",
      "year": 2026,
      "venue": "BMJ Public Health 4:e004086; doi:10.1136/bmjph-2025-004086",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13599929/",
      "type": "Research",
      "scope": "17 studies focused on ages 18–29; searched publications through November 2024; narrative synthesis."
    },
    {
      "id": 6,
      "authors": "Chiossi et al.",
      "title": "Short-Form Videos Degrade Our Capacity to Retain Intentions: Effect of Context Switching On Prospective Memory",
      "year": 2023,
      "venue": "CHI 2023; author manuscript, arXiv:2302.03714",
      "url": "https://arxiv.org/abs/2302.03714",
      "type": "Research",
      "scope": "Between-group experiment, N=60; short-term prospective memory task, including TikTok."
    },
    {
      "id": 7,
      "authors": "Castelo et al.",
      "title": "Blocking mobile internet on smartphones improves sustained attention, mental health, and subjective well-being",
      "year": 2025,
      "venue": "PNAS Nexus 4:pgaf017; doi:10.1093/pnasnexus/pgaf017",
      "url": "https://academic.oup.com/pnasnexus/article/4/2/pgaf017/8016017",
      "type": "Research",
      "scope": "Randomized two-week mobile internet block; 467 committed participants; broad intervention."
    },
    {
      "id": 8,
      "authors": "Allcott, Braghieri, Eichmeyer & Gentzkow",
      "title": "The Welfare Effects of Social Media",
      "year": 2020,
      "venue": "American Economic Review 110:629–676; doi:10.1257/aer.20190658",
      "url": "https://www.aeaweb.org/articles?id=10.1257/aer.20190658",
      "type": "Research",
      "scope": "Randomized Facebook deactivation for four weeks; adult volunteers before the 2018 US midterms."
    },
    {
      "id": 9,
      "authors": "Braghieri, Levy & Makarin",
      "title": "Social Media and Mental Health",
      "year": 2022,
      "venue": "American Economic Review 112:3660–3693; doi:10.1257/aer.20211218",
      "url": "https://www.aeaweb.org/articles?id=10.1257/aer.20211218",
      "type": "Research",
      "scope": "Staggered Facebook introduction at US colleges; quasi-experimental, early social media."
    },
    {
      "id": 10,
      "authors": "Allcott, Gentzkow & Song",
      "title": "Digital Addiction",
      "year": 2022,
      "venue": "American Economic Review 112:2424–2463; doi:10.1257/aer.20210867",
      "url": "https://www.aeaweb.org/articles?id=10.1257/aer.20210867",
      "type": "Research",
      "scope": "Randomized incentives and limits plus a structural economic model; social media generally."
    },
    {
      "id": 11,
      "authors": "Tam & Inzlicht",
      "title": "Fast-forward to boredom: How switching behavior on digital media makes people more bored",
      "year": 2024,
      "venue": "Journal of Experimental Psychology: General; publisher research summary; doi:10.1037/xge0001639",
      "url": "https://www.apa.org/news/press/releases/2024/08/online-videos-boredom",
      "type": "Research",
      "scope": "Seven experiments; short-term video switching and boredom, not clinical impairment."
    },
    {
      "id": 12,
      "authors": "Maza et al.",
      "title": "Association of Habitual Checking Behaviors on Social Media With Longitudinal Functional Brain Development",
      "year": 2023,
      "venue": "JAMA Pediatrics 177:160–167; doi:10.1001/jamapediatrics.2022.4924",
      "url": "https://jamanetwork.com/journals/jamapediatrics/fullarticle/2799812",
      "type": "Research",
      "scope": "Adolescent longitudinal neuroimaging; observational social media checking."
    },
    {
      "id": 13,
      "authors": "Orben et al.",
      "title": "Windows of developmental sensitivity to social media",
      "year": 2022,
      "venue": "Nature Communications 13:1649; doi:10.1038/s41467-022-29296-3",
      "url": "https://www.nature.com/articles/s41467-022-29296-3",
      "type": "Research",
      "scope": "UK observational datasets; age-dependent associations and bidirectionality."
    },
    {
      "id": 14,
      "authors": "Orben & Przybylski",
      "title": "The association between adolescent well-being and digital technology use",
      "year": 2019,
      "venue": "Nature Human Behaviour 3:173–182; doi:10.1038/s41562-018-0506-1",
      "url": "https://www.nature.com/articles/s41562-018-0506-1",
      "type": "Research",
      "scope": "Specification curve analysis; broad digital technology use, largely before Reels and Shorts."
    },
    {
      "id": 15,
      "authors": "Carter et al.",
      "title": "Association Between Portable Screen-Based Media Device Access or Use and Sleep Outcomes: A Systematic Review and Meta-analysis",
      "year": 2016,
      "venue": "JAMA Pediatrics 170:1202–1208; doi:10.1001/jamapediatrics.2016.2341",
      "url": "https://pubmed.ncbi.nlm.nih.gov/27802500/",
      "type": "Research",
      "scope": "Bedtime portable devices and sleep in children; not specific to short-form video."
    },
    {
      "id": 16,
      "authors": "Yin et al.",
      "title": "Relationship of Sleep Duration With All-Cause Mortality and Cardiovascular Events: A Systematic Review and Dose-Response Meta-Analysis of Prospective Cohort Studies",
      "year": 2017,
      "venue": "Journal of the American Heart Association 6:e005947; doi:10.1161/JAHA.117.005947",
      "url": "https://pubmed.ncbi.nlm.nih.gov/28889101/",
      "type": "Research",
      "scope": "Adult prospective sleep cohorts; observational mortality associations, not a scrolling risk estimate."
    },
    {
      "id": 17,
      "authors": "Faverio, Park & Gottfried / Pew Research Center",
      "title": "Teens’ Experiences on TikTok, Instagram and Snapchat",
      "year": 2026,
      "venue": "US survey of 1,458 teenagers aged 13–17 and their parents; fieldwork September–October 2025",
      "url": "https://www.pewresearch.org/internet/2026/04/15/teens-experiences-on-tiktok-instagram-and-snapchat/",
      "type": "Measurement",
      "scope": "Self-reported experiences, reasons for use, benefits and harms; not a clinical causal study."
    },
    {
      "id": 18,
      "authors": "TikTok",
      "title": "How TikTok recommends content",
      "year": 2026,
      "venue": "TikTok Help Center; accessed 9 November 2026",
      "url": "https://support.tiktok.com/en/using-tiktok/exploring-videos/how-tiktok-recommends-content",
      "type": "Platform",
      "scope": "Platform description of recommendation signals; not independent validation of welfare effects."
    },
    {
      "id": 19,
      "authors": "Meta",
      "title": "How AI Influences What You See on Facebook and Instagram",
      "year": 2023,
      "venue": "Meta Newsroom; system cards and user controls",
      "url": "https://about.fb.com/news/2023/06/how-ai-ranks-content-on-facebook-and-instagram/",
      "type": "Platform",
      "scope": "Platform explanation of personalized ranking; not independent health evidence."
    },
    {
      "id": 20,
      "authors": "World Health Organization",
      "title": "Tobacco and nicotine",
      "year": 2026,
      "venue": "Fact sheet, 26 June 2026",
      "url": "https://www.who.int/news-room/fact-sheets/detail/tobacco",
      "type": "Public health",
      "scope": "More than 7 million annual global deaths; includes second-hand smoke. Annual burden, not a 2026 death count."
    },
    {
      "id": 21,
      "authors": "World Health Organization",
      "title": "Alcohol",
      "year": 2024,
      "venue": "Fact sheet, 28 June 2024; 2019 burden",
      "url": "https://www.who.int/news-room/fact-sheets/detail/alcohol",
      "type": "Public health",
      "scope": "2.6 million global alcohol-attributable deaths in 2019."
    },
    {
      "id": 22,
      "authors": "World Health Organization",
      "title": "Global call to action on lead poisoning prevention",
      "year": 2024,
      "venue": "WHO statement, 18 October 2024",
      "url": "https://www.who.int/news/item/18-10-2024-global-call-to-action-on-lead-poisoning-prevention",
      "type": "Public health",
      "scope": "Approximately 1.5 million annual deaths associated with all lead exposure; not all attributable to petrol."
    },
    {
      "id": 23,
      "authors": "World Health Organization",
      "title": "Gambling",
      "year": 2024,
      "venue": "Fact sheet, 2 December 2024",
      "url": "https://www.who.int/news-room/fact-sheets/detail/gambling",
      "type": "Public health",
      "scope": "Health, financial and family harms; limited standardized global harm estimation."
    },
    {
      "id": 24,
      "authors": "UN Environment Programme",
      "title": "Era of leaded petrol over, eliminating a major threat to human and planetary health",
      "year": 2021,
      "venue": "UNEP, 30 August 2021",
      "url": "https://www.unep.org/en/news-and-stories/press-release/era-leaded-petrol-over-eliminating-major-threat-human-and-planetary",
      "type": "Public health",
      "scope": "Phaseout benefit estimated at more than 1.2 million avoided premature deaths annually; a different counterfactual."
    },
    {
      "id": 25,
      "authors": "World Health Organization",
      "title": "Physical activity",
      "year": 2026,
      "venue": "Fact sheet, 4 November 2026",
      "url": "https://www.who.int/news-room/fact-sheets/detail/physical-activity",
      "type": "Public health",
      "scope": "Physical inactivity and health; establishes neither the amount displaced by scrolling nor a platform-specific risk."
    },
    {
      "id": 26,
      "authors": "International Committee of the Red Cross & Japanese Red Cross Society",
      "title": "80 years after the atomic bombings of Hiroshima and Nagasaki: A call to eliminate nuclear weapons",
      "year": 2025,
      "venue": "Joint statement, 5 August 2025",
      "url": "https://www.icrc.org/en/statement/80-years-atomic-bomb-hiroshima-nagasaki-call-eliminate-nuclear-weapons",
      "type": "Public health",
      "scope": "Immediate and enduring humanitarian consequences of nuclear weapons; no comparison with digital-media harm."
    }
  ],
  "usageBenchmarks": [
    {
      "platform": "TikTok",
      "minutes": 50,
      "population": "UK, ages 15–17",
      "base": "Internet users",
      "year": "May 2025",
      "source": 1
    },
    {
      "platform": "Instagram",
      "minutes": 36,
      "population": "UK, ages 15–17",
      "base": "Internet users; whole app",
      "year": "May 2025",
      "source": 1
    },
    {
      "platform": "TikTok",
      "minutes": 49,
      "population": "UK, ages 18–34",
      "base": "Monthly visitors ÷ days",
      "year": "May 2025",
      "source": 1
    },
    {
      "platform": "TikTok",
      "minutes": 28,
      "population": "UK, ages 18+",
      "base": "Monthly visitors ÷ days",
      "year": "May 2025",
      "source": 1
    },
    {
      "platform": "Instagram",
      "minutes": 20,
      "population": "UK, ages 18+",
      "base": "Monthly visitors ÷ days; whole app",
      "year": "May 2025",
      "source": 1
    },
    {
      "platform": "TikTok",
      "minutes": 132,
      "population": "Monitored children, ages 4–18",
      "base": "App users; selected families",
      "year": "2025",
      "source": 2
    },
    {
      "platform": "Instagram",
      "minutes": 79,
      "population": "Monitored children, ages 4–18",
      "base": "App users; whole app",
      "year": "2025",
      "source": 2
    }
  ],
  "usageTrend": [
    {
      "year": 2021,
      "TikTok": 91,
      "Instagram": 41
    },
    {
      "year": 2022,
      "TikTok": 107,
      "Instagram": 45
    },
    {
      "year": 2023,
      "TikTok": 112,
      "Instagram": 63
    },
    {
      "year": 2024,
      "TikTok": 120,
      "Instagram": 79
    },
    {
      "year": 2025,
      "TikTok": 132,
      "Instagram": 79
    }
  ],
  "mentalHealthCorrelations": [
    {
      "outcome": "Depressive symptoms",
      "use": "All measures",
      "r": 0.24,
      "low": 0.15,
      "high": 0.33,
      "source": 4,
      "sourceUrl": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12998613/",
      "interval": "reported 95% CI",
      "causal": false
    },
    {
      "outcome": "Anxiety symptoms",
      "use": "All measures",
      "r": 0.26,
      "low": 0.17,
      "high": 0.35,
      "source": 4,
      "sourceUrl": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12998613/",
      "interval": "reported 95% CI",
      "causal": false
    },
    {
      "outcome": "Anxiety symptoms",
      "use": "Problematic use",
      "r": 0.38,
      "low": 0.33,
      "high": 0.43,
      "source": 4,
      "sourceUrl": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12998613/",
      "interval": "reported 95% CI",
      "causal": false
    },
    {
      "outcome": "Anxiety symptoms",
      "use": "Routine use",
      "r": -0.02,
      "low": -0.18,
      "high": 0.14,
      "source": 4,
      "sourceUrl": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12998613/",
      "interval": "reported 95% CI",
      "causal": false
    },
    {
      "outcome": "Loneliness",
      "use": "Problematic use",
      "r": 0.33,
      "low": 0.25,
      "high": 0.41,
      "source": 4,
      "sourceUrl": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12998613/",
      "interval": "reported 95% CI",
      "causal": false
    },
    {
      "outcome": "Boredom",
      "use": "Problematic use",
      "r": 0.42,
      "low": 0.29,
      "high": 0.53,
      "source": 4,
      "sourceUrl": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12998613/",
      "interval": "reported 95% CI",
      "causal": false
    }
  ],
  "evidence": [
    {
      "id": "attention",
      "outcome": "Attention & inhibitory control",
      "scope": "Short-form video",
      "design": "Meta-analysis",
      "source": 3,
      "result": "Attention r = −0.38; inhibition r = −0.41; overall cognition r = −0.34.",
      "quality": "Association: moderate confidence. Causality: low.",
      "limitation": "Heterogeneous exposures include problematic use. These correlations are not percentage reductions in attention. CIs were not extracted from the accessible abstract; no whiskers are invented."
    },
    {
      "id": "mental",
      "outcome": "Depression & anxiety",
      "scope": "Short-form video",
      "design": "Meta-analysis",
      "source": 4,
      "result": "Depression r = 0.24 [0.15, 0.33]; anxiety r = 0.26 [0.17, 0.35].",
      "quality": "Association: moderate confidence. Causality: low.",
      "limitation": "Baseline correlations; routine and problematic use differ. Symptom overlap and shared self-report can inflate associations. The plot above shows reported 95% CIs."
    },
    {
      "id": "memory",
      "outcome": "Prospective memory",
      "scope": "TikTok",
      "design": "Experiment",
      "source": 6,
      "result": "N = 60; TikTok condition performed worse on remembering intended actions.",
      "quality": "Immediate task effect: limited experimental evidence.",
      "limitation": "Small, brief laboratory intervention bundles content, format and switching. Does not establish permanent memory loss. No standardized effect or CI is transcribed here."
    },
    {
      "id": "mobile",
      "outcome": "Sustained attention & well-being",
      "scope": "Broader technology",
      "design": "Randomized trial",
      "source": 7,
      "result": "Two-week mobile internet block improved measured attention and reported well-being.",
      "quality": "Causal for this intervention; indirect for short video.",
      "limitation": "Only 119 of 467 committed participants met the preregistered compliance threshold. Volunteers and follow-up limits constrain generalization; no Reels-specific treatment."
    },
    {
      "id": "sleep",
      "outcome": "Sleep quantity",
      "scope": "Broader technology",
      "design": "Meta-analysis",
      "source": 15,
      "result": "Bedtime device use: inadequate sleep OR = 2.17 [1.42, 3.32].",
      "quality": "Association: moderate confidence. Causality: low.",
      "limitation": "Odds ratio, not risk ratio or mortality hazard. Older studies of portable devices cannot identify the effect of TikTok or Reels."
    },
    {
      "id": "neuro",
      "outcome": "Adolescent brain development",
      "scope": "Broader technology",
      "design": "Longitudinal",
      "source": 12,
      "result": "Habitual checking was associated with changing neural responses to social anticipation.",
      "quality": "Longitudinal association; causal direction unresolved.",
      "limitation": "Functional activation differences do not demonstrate brain damage, arrested maturation, or a loss of intelligence."
    },
    {
      "id": "academic",
      "outcome": "Academic functioning",
      "scope": "Broader technology",
      "design": "Natural experiment",
      "source": 9,
      "result": "Early Facebook rollout increased reported academic impairment attributed to poor mental health.",
      "quality": "Quasi-experimental, subject to rollout assumptions.",
      "limitation": "Early Facebook and college populations; not an estimate of test-score or earnings losses from short video. Reels-specific causal academic effects remain a gap."
    },
    {
      "id": "wellbeing",
      "outcome": "Subjective well-being",
      "scope": "Broader technology",
      "design": "Randomized trial",
      "source": 8,
      "result": "Four-week Facebook deactivation improved well-being but reduced factual news knowledge.",
      "quality": "Causal for the studied deactivation and sample.",
      "limitation": "Some replacement time went to television. A benefit from deactivation does not make every hour of use harmful."
    },
    {
      "id": "young",
      "outcome": "Executive function & emotional regulation",
      "scope": "Short-form video",
      "design": "Systematic review",
      "source": 5,
      "result": "17 studies in young adults; mixed methods and heterogeneous findings.",
      "quality": "Preliminary; insufficient for a pooled causal effect.",
      "limitation": "Age focus 18–29; largely observational, self-reported exposure. Publication in 2026 does not mean the underlying search included 2026 studies."
    }
  ],
  "formulas": {
    "lifetimeCalendarYears": "minutesPerDay * (endingAge - startingAge) / 1440",
    "wakingShare": "minutesPerDay / (16 * 60)",
    "annualGlobalPersonYears": "uniqueDailyAudience * combinedDailyMinutes / 1440",
    "platformMinutes": "combinedDailyMinutes * weight / sumOfWeights",
    "equivalentOpportunityYears": "annualGlobalPersonYears * assumedNetValueGap",
    "annualOpportunityValue": "uniqueDailyAudience * dailyMinutes / 60 * 365.25 * displacedWorkShare * realizationShare * hourlyValue",
    "individualPresentValue": "sum(annualOpportunityValuePerPerson / (1 + realDiscountRate) ** (yearIndex + 0.5)), yearIndex=0..66",
    "hypotheticalQalys": "uniqueAudience * assumedCausalExcessAffectedShare * assumedUtilityDecrement * durationYears"
  }
}