Evidence-based · Fully cited Informational only — not medical advice
The Coffee Health Report Evidence · Data · Sources
The evidence, weighed and cited

Coffee & your health, without the hype

The world's most-studied drink, examined stream by stream — cortisol and stomach acid, anxiety, mood, blood pressure, longevity, and the coffee industry's real scandals. Strong evidence is separated from weak, and every number links to a source.

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Informational, not medical advice. This report summarises published research to help you think — it is not a substitute for a doctor. Much of the evidence is observational (association, not proof of cause). Talk to a qualified professional before changing your caffeine intake, especially if you are pregnant, take medication, or have a heart, anxiety or digestive condition.

Who drinks the most coffee

Consumption per person, per year — leading nations

Approximate figures compiled from ICO / national data. Values vary by source and year.49

How much caffeine is in your cup?

Milligrams per typical serving

Source: Mayo Clinic caffeine table (USDA/FDA), 2025.33 Real cups vary with size, bean and brew.

Roughly two-thirds of adults in many countries drink coffee daily, and researchers have followed millions of them for decades. The single most comprehensive synthesis to date — an umbrella review of 201 meta-analyses — concluded that moderate coffee drinking is "more often associated with benefit than harm," with the lowest all-cause mortality at about three to four cups a day.1 But "coffee is healthy" is too blunt. The same caffeine that sharpens attention also raises cortisol, nudges blood pressure, and can tip sensitive people into anxiety. This report walks through each effect, flags how strong the evidence really is, and ends with the scandals that are actually worth your attention — fraud and labour, more than chemistry.

Stress hormone & stomach acid

Cortisol and hydrochloric acid (HCl)

"HCL" points to two different things coffee touches — cortisol, the stress hormone, and hydrochloric acid (HCl), your stomach acid. Coffee measurably affects both.

Caffeine and cortisol

In a controlled, placebo-based crossover study, a caffeine dose of 3.3 mg/kg — the equivalent of two to three cups — raised cortisol by about 30% and the pituitary hormone ACTH by about 33%, peaking around 60 minutes after drinking.5 In other words, coffee switches on part of the same hormonal stress axis that a tense meeting does. Moderate–strong

The important nuance is tolerance. In daily drinkers, the morning cortisol response is largely abolished — but a response returns after an afternoon dose, so tolerance is only partial.6 And caffeine's cortisol bump adds on top of psychological stress: taken before a mental-stress task, it pushed cortisol higher than the stressor alone.7 For someone stacking several coffees onto a long, screen-heavy, deadline-driven day, that stacking is the mechanism to be aware of. Moderate

Practical read If you feel wired and tense, the fix isn't necessarily zero coffee — it's dose and timing. Front-load caffeine earlier, cap the total, and don't rely on it to paper over lost sleep.

Caffeine and stomach acid (HCl)

Coffee stimulates the stomach to secrete hydrochloric acid and the hormone gastrin. The classic dose-response study is revealing: on a cup-equivalent basis, regular coffee drove acid output to 20.9 mEq/hr, decaf to 16.5, but pure caffeine only to 8.4.8 Because decaf is nearly as potent as regular, caffeine is not the main culprit — other compounds created during roasting are.9,10 Darker roasts, which contain more of the acid-suppressing compound N-methylpyridinium, tend to stimulate less. Moderate–strong

Does that acid translate into reflux or ulcers? At the population level, meta-analyses find no significant association between coffee and GERD, and none with peptic ulcers.10 Heavy intake aggravates symptoms in some individuals, but that's personal, not universal — and switching to decaf is not a guaranteed fix. Strong (population)

Coffee switches on the stress axis

Peak hormone rise vs placebo after ~2–3 cups (at rest)

Source: Lovallo et al., Pharmacol Biochem Behav 1996 (n=47).5

Decaf isn't the gentle option you'd expect

Maximal gastric (HCl) acid output, cup-equivalent

Source: Cohen & Booth, New England Journal of Medicine 1975.8
Jitters, palpitations, panic

Coffee and anxiety

Caffeine blocks adenosine and triggers a release of adrenaline, revving the sympathetic "fight-or-flight" system.37 The racing heart and restlessness that follow are physically hard to tell apart from anxiety — which is why dose and personal sensitivity matter so much.

A big dose provokes panic — mostly in the vulnerable

Panic-attack rate after a ~480 mg caffeine challenge (≈5 cups at once)

Sources: Klevebrant & Frick meta-analysis, Gen Hosp Psychiatry 2021; Nardi et al. challenge trials.11,12

Dose is (almost) everything

Everyday servings are reassuring: a 2025 randomised trial found 150 mg of caffeine did not raise anxiety even in people with panic disorder.14 Risk climbs with dose — anxiety symptoms become common above roughly 400 mg a day in sensitive people,33,37 and a meta-analysis confirms anxiety rises with intake, steeply beyond 400 mg.15 Strong

The extreme end is a laboratory "caffeine challenge" of about 480 mg — five cups at once. Pooled trials show this triggered a panic attack in about 54% of people with panic disorder, versus under 2% of healthy controls.11 That's a stress test, not a normal habit — but it maps the vulnerability sharply. Strong

Who is most sensitive

People with panic or anxiety disorders react most. So do carriers of a common ADORA2A adenosine-receptor variant, who showed more caffeine-induced anxiety at just 150 mg,13 and "slow metabolisers" (CYP1A2) who clear caffeine sluggishly, so an afternoon cup lingers into the night. The DSM-5 formally recognises caffeine-induced anxiety disorder.15 Moderate

The desk-work loop Caffeine blocks the same adenosine that builds sleep pressure. Using coffee to push through a long screen day can cost you sleep, and poorer sleep raises baseline stress — so the next day's coffee feels stronger. Anxiety-prone knowledge workers feel this loop most.16
Mood & mental health

Coffee, depression and mood

Here the epidemiology leans, perhaps surprisingly, protective — but it is observational, and "more" is not "better."

An inverse association

Large cohorts consistently link caffeinated coffee (not decaf) to lower depression risk. In 50,000+ women, those drinking four or more cups a day had about 20% lower risk of depression;17 dose-response meta-analyses put the reduction near 8% per cup,18 flattening out around two to three cups.19,21 Pooled Harvard cohorts also found markedly lower completed-suicide risk in coffee drinkers.20 Plausible mechanisms include caffeine's effect on dopamine and serotonin turnover. Moderate

Read it carefully

These are associations, not proof. Depressed people may simply drink less coffee (reverse causation), and smoking confounds every analysis.20 Crucially, the benefit is not open-ended: a Finnish study found higher suicide risk at eight or more cups a day, a J-shaped curve.20 Very high intake, and caffeine withdrawal, can worsen mood and anxiety. The honest summary: moderate coffee is associated with better mood outcomes; loading up is not a treatment. Weak / observational

If you're struggling with your mood, coffee is not a substitute for care. This is a sensitive topic — please reach out to a qualified professional or a trusted person for support.

Coffee drinkers, lower risk — up to a point

Relative risk vs people who drink ≤1 cup per week

Sources: Lucas et al., Arch Intern Med 2011 (depression); Lucas et al., World J Biol Psychiatry 2014 (suicide).17,20
Cardiovascular & blood pressure

Coffee, the heart and blood pressure

A single cup gives a brief blood-pressure nudge; a lifelong habit looks broadly neutral to protective. The exception is people with severe, uncontrolled hypertension.

Coffee raises blood pressure far less than pure caffeine

Mean change vs control after ≥7 days of intake (RCT meta-analysis)

Source: Noordzij et al., J Hypertens 2005 (16 RCTs).22

Acute vs habitual

A caffeine dose of 200–300 mg raises blood pressure about 3–8 mmHg systolic, peaking at 60–90 minutes and fading within 2–4 hours.23 But delivered as coffee, the effect is much smaller than pure caffeine (above), because coffee's other compounds blunt it — and regular drinkers develop tolerance.22,36 Across cohorts of 200,000+ people, habitual coffee is not associated with higher long-term hypertension risk, and is slightly protective per cup, though a J-shape means a small bump at light intake.24,25 Strong

Reassuringly, moderate coffee does not raise atrial-fibrillation risk and may modestly lower it,26 and cardiovascular mortality follows a U-shape with the lowest risk near three cups.27

Who should limit In people with severe (grade 2–3) hypertension, two or more cups a day was linked to double the risk of cardiovascular death — one cup was not.28 Caution also applies to some arrhythmias and high-dose energy drinks. And skip caffeine for 30 minutes before a blood-pressure reading.36

Habitual coffee and hypertension risk

Relative risk by cups per day (dose-response meta-analysis)

Source: Xie et al., J Hum Hypertens 2018 (10 cohorts, ~244,000 people).24 A separate meta-analysis notes a small risk increase at light (1–3 cups) intake.25
Longevity, metabolism & limits

The benefits — and how much is safe

This is where coffee's reputation is earned: large reviews tie moderate intake to lower mortality and disease risk. Just remember the evidence is observational, and smoking is the confounder that lurks behind all of it.

A U-shaped longevity curve

All-cause mortality (hazard ratio) by cups per day

Source: Freedman et al., NEJM 2012 (NIH-AARP, ~402,000).2 Corroborated by the EPIC cohort (521,000) and pooled meta-analyses.3,4 The umbrella review puts the nadir near 3 cups (RR 0.83).1

Type 2 diabetes falls with each cup

Relative risk by cups per day

Source: Ding et al., Diabetes Care 2014 (28 studies, 1.1M).29 Decaf works too (~6% per cup).

What the strong evidence shows

Beyond longevity and diabetes, moderate coffee is linked to roughly 25% lower Parkinson's disease risk30 and about 44% lower cirrhosis risk per two cups a day.31 Caffeine's boost to alertness and attention at 75 mg or more is one of the few effects proven by randomised trials, not just cohorts.16 Coffee is also the single largest source of antioxidants (polyphenols) in many Western diets.32 Alzheimer's protection, by contrast, is mixed and shouldn't be overstated. Strong (mostly)

Official safe limits

Regulators converge on 400 mg of caffeine a day — about four 8-oz cups — as safe for healthy adults, with single doses around 200 mg.16,33,34 Pregnant and breastfeeding people should stay at or below 200 mg/day;35 children and teens around 3 mg/kg. Rapidly consuming ~1,200 mg risks toxicity.34

Coffee dominates dietary antioxidants

Sources of total antioxidant intake (Norway), mmol/day

Source: Svilaas et al., J Nutr 2004.32 Diet-dependent; coffee's share reflects heavy Nordic intake.

Caffeine, in reference points

Milligrams — the numbers that matter

Sources: EFSA 2015; FDA; ACOG.16,34,35
Lawsuits, contaminants & ethics

Scandals & safety

Two different stories live here. On contaminants, the honest finding is usually "present but low and regulated." The genuine scandals are elsewhere — in fraud and labour.

The Lindt lawsuit is about chocolate, not coffee

A widely shared "heavy metals" lawsuit is frequently misattributed to coffee. To be clear: the Lindt lead-and-cadmium case concerns dark chocolate. After Consumer Reports detected lead and cadmium in all 28 dark-chocolate bars it tested in 2022,38 class actions followed, and in September 2024 a federal judge rejected Lindt's "puffery" defense and let the case proceed.39 Cadmium enters cacao from soil; lead settles onto beans after harvest. Coffee takes up far less cadmium than cacao. Court record

The coffee cancer-warning fight — resolved

In California, a Prop 65 suit (filed 2010) argued coffee needed a cancer warning for acrylamide, a compound formed in roasting. A 2018 ruling briefly agreed — but in 2019 the state regulator OEHHA declared coffee poses "no significant risk," and courts affirmed the exemption in 2022.40,41 Coffee carries no warning. Acrylamide is real (IARC "probably carcinogenic") and coffee is a notable dietary source — the one contaminant genuinely worth a footnote. Settled

Heavy metals & mould: mostly reassuring

Coffee itself is among the cleaner food categories: a brewed cup delivers well under 3% of health-based limits for lead and cadmium.42 Ochratoxin A, a mould toxin, is detectable in roughly half of samples but usually far below EU limits (3.0 µg/kg roasted), roasting destroys most of it, and coffee is only ~9–10% of dietary intake.42,43 On pesticides, a 2025 lab study found the glyphosate breakdown product AMPA in 72% of products (including organic) — but that's AMPA, not glyphosate (found in just 2 of 57), and all were below per-serving limits.44 Well-supported

Mould toxin: usually well under the limit

Ochratoxin A — typical levels vs EU legal limits (µg/kg)

Limits: EU Reg. 2023/915. Typical levels: survey data.42,43

The real product scandal: fraud

Undeclared adulteration found in tested products (%)

Sources: OPSON VIII; Quadram Institute 2018; and market studies. Some are enriched samples, not population rates.45

The scandals that deserve your attention

Coffee is among the most adulterated foods — cut with husks, twigs and grains, or sold as "100% Arabica" while containing cheaper robusta (found in 10–36% of tested products).45 Origin fraud is rife: roughly 2.7 million lb of genuine Kona coffee is grown yearly, yet over 20 million lb is sold as "Kona," producing $33 million in labelling settlements.48 Most serious of all is labour: the U.S. Department of Labor flags coffee for child and/or forced labour in 17 countries (Brazil and Côte d'Ivoire for both),46 and Brazilian authorities have rescued 3,700+ workers from slavery-like conditions on coffee farms since 1996 — with cases tied even to certified estates.47 Fresh 2025 lawsuits and import petitions target major brands; those remain allegations, not proven findings.47

  1. 2000
    Kona Kai Farms fraud Fraud

    3.6M lb of Central American coffee rebagged as "Pure Kona"; owner convicted of wire fraud.48

  2. 2010
    CERT sues Starbucks & ~90 roasters Legal

    California Prop 65 acrylamide case filed; begins an 8-year fight.41

  3. 2016
    "Bitter Coffee" exposé, Brazil Ethics

    ~101 workers freed from slavery-like conditions in supply chains (2009–15).47

  4. 2018
    "100% Arabica" fraud quantified Fraud

    Quadram Institute finds ~10% of products deliberately adulterated with robusta.45

  5. 2019
    Coffee exempted from Prop 65 warning Safety

    OEHHA rules acrylamide in coffee poses "no significant risk."40

  6. 2020
    Child labour on certified farms Ethics

    A Channel 4 investigation films children on Nespresso/Starbucks-linked Guatemala farms.

  7. 2022
    Consumer Reports: metals in dark chocolate Legal

    Lead & cadmium in all 28 bars tested — triggers the Lindt class actions (chocolate, not coffee).38

  8. 2023
    Kona labelling settlements reach $33.4M Fraud

    Final $12M settlement approved over falsely labelled "Kona" coffee.48

  9. 2024
    Judge rejects Lindt "puffery" defense Legal

    Heavy-metals chocolate case proceeds (ongoing in 2026).39

  10. 2025
    Forced-labour suit & import petition Ethics

    Major brands named over Brazilian coffee — allegations, not yet adjudicated.47

Special topic · Mental health

Coffee & bipolar disorder — treated vs untreated

For people living with bipolar disorder, caffeine is not a neutral drink. It interacts with the medications that keep the illness stable and with the sleep that keeps mood level. The evidence is mostly observational, so nothing here is a rule — but the signals are consistent enough that psychiatry guidelines routinely raise it.

Important safety note. Bipolar disorder is a serious medical condition. Nothing here is medical advice, and it is not a reason to start, stop or change any medication or your caffeine intake on your own. If you take lithium, do not abruptly cut or quit caffeine without telling your prescriber — see why below. Always work with your clinician.
~2.8×Higher blood caffeine in people with bipolar disorder vs matched controls51
2.7–10.7%Manic "switch" rate from sleep loss — the pathway caffeine feeds57
~24%Reported rise in blood lithium after stopping caffeine52
OR 2.42Coffee's association with suicidal acts in bipolar patients58

The only systematic review dedicated to this question examined 17 studies and concluded the evidence is "not conclusive" — but it found a recurring signal: sharp increases in caffeine often precede manic symptoms, and changes in caffeine move lithium levels.50 People with bipolar disorder also tend to consume more caffeine than average — in one controlled comparison their blood caffeine ran roughly 2.8× that of matched controls.51

If you are treated (on medication)

Lithium — the interaction that matters most. Caffeine makes the kidneys excrete lithium faster, so heavy coffee can lower lithium toward a level that no longer protects you. The more dangerous move is the reverse: if a heavy coffee drinker on lithium abruptly quits, lithium clearance falls and blood levels climb — reported at around +24%, enough to reach toxic levels.52 In one documented case an 87% overnight caffeine cut pushed lithium to a supratherapeutic 2.1 mmol/L.53 Hence the clinical rule: keep caffeine steady, and change it only gradually, with a lithium level check.

Antipsychotics (clozapine, olanzapine). These share a liver enzyme (CYP1A2) with caffeine. Adding caffeine raised clozapine levels ~19% in a trial;54 a 5-day caffeine-free diet dropped them ~47%.55 So a sudden caffeine change can swing antipsychotic levels too — worth flagging to your prescriber.

If you are untreated (or undiagnosed)

There is no lithium to destabilise — but there is also no mood-stabiliser buffer and no monitoring. Caffeine's stimulant and sleep-disrupting effects can push toward mania unchecked. In online communities, people with bipolar disorder report caffeine as the second most common way they deliberately try to lift out of a depressive episode (after sleep reduction) — and about three-quarters said ending a depression was the goal.60 Using caffeine to "push through" low mood can mask the illness and delay getting help. This is also the least-studied group, so caution — not false reassurance — is the honest stance.

The sleep pathway — the strongest thread

Caffeine measurably damages sleep even when taken 6 hours before bed,56 and sleep loss is one of the best-documented triggers of mania — a "final common pathway" by which many triggers act, with a manic switch in 2.7–10.7% of sleep-deprivation cases.57 Caffeine → lost sleep → destabilised mood is the mechanism psychiatry worries about most, and it is why protecting sleep is the highest-value lever here.

Suicide risk — a careful, two-sided picture

In the general population, moderate coffee is linked to lower suicide risk — across three large US cohorts, 2–3 cups/day carried a relative risk around 0.55.59 That protective signal does not appear to extend to bipolar disorder: the one study to look specifically at bipolar patients found coffee drinking associated with more suicidal acts (odds ratio 2.42), rising with cups per day.58 This is an association, not proof of cause — heavy caffeine use in this group likely reflects, or worsens, agitation, anxiety and broken sleep. The point is not "coffee causes harm" but that the reassuring general-population data should not be applied to bipolar disorder.

Practical, sourced pointers — discuss with your clinician

  • Keep intake steady. Avoid sudden jumps or quitting cold — change gradually.50
  • On lithium, treat caffeine like a drug interaction. Don't sharply increase or stop it without telling your prescriber; big changes warrant a lithium level check.52,53
  • Protect sleep first. Cut afternoon and evening caffeine. Psychoeducation programmes often use a rough cap of about two caffeinated drinks a day when mood is stable.61
  • Avoid energy drinks and high-dose "binge" caffeine, especially if hypomania, mania or mixed features are emerging.50
  • Watch a caffeine spike as a warning sign. A sudden craving or jump in intake can be an early signal of mania — flag it rather than ride it.50
  • Don't self-medicate depression with caffeine. It worsens sleep and, in bipolar disorder, can tip toward mania — seek assessment instead.60
About our "quit caffeine" protocol. The step-down guide on this site is written for the general reader. If you have bipolar disorder — especially if you take lithium — do not follow it on your own: an abrupt drop in caffeine can raise your lithium toward toxicity. Any taper should be planned with your prescriber and paired with a lithium level check.

According to PubMed. Educational information, not medical advice. Sources 50–61 below.

Answer engine & quick reference

Frequently asked questions

Concise, sourced answers to the questions people actually ask about coffee and health.

Is coffee good or bad for you?

For most healthy adults, moderate coffee (about 3–4 cups a day) is linked in large reviews to lower overall death rates — around 17% lower — and to lower risk of type 2 diabetes, Parkinson's disease and liver disease.1 The evidence is observational (association, not proof), and effects depend on dose, timing, genetics and your health conditions.

How much caffeine is safe per day?

The FDA and EFSA consider up to 400 mg/day — about four 8-oz cups of brewed coffee — safe for healthy adults, with single doses near 200 mg.16,34 Pregnant and breastfeeding people should stay at or below 200 mg/day.35

Does coffee raise cortisol?

Yes — about 30% after 2–3 cups, peaking near 60 minutes.5 Daily drinkers develop partial tolerance (the morning response fades), but caffeine still adds to the cortisol rise from mental stress.6,7

Can coffee cause anxiety?

Everyday servings (95–150 mg) rarely trigger anxiety, and 150 mg didn't raise it even in panic-disorder patients in a 2025 trial.14 Risk climbs above ~400 mg/day in sensitive people; a large single dose (~480 mg) triggered panic in ~54% of panic-disorder patients vs under 2% of controls.11

Is coffee bad for high blood pressure?

A dose gives a short 3–8 mmHg rise that fades in a few hours, and habitual coffee is largely neutral for hypertension risk.23,24 But in severe, uncontrolled hypertension, 2+ cups/day was linked to double the cardiovascular-death risk — so caution there.28

Does coffee increase stomach acid?

Yes, and decaf does it almost as strongly as regular, so caffeine isn't the main cause — roast compounds are.8 Dark roasts stimulate less. Population studies find no clear coffee–reflux link, though heavy intake bothers some people.10

Was Lindt sued over lead in coffee?

No — the Lindt lead-and-cadmium lawsuits concern dark chocolate, not coffee. A judge let the case proceed in 2024 after rejecting a "puffery" defense.38,39

Does coffee contain mould or mycotoxins?

Trace ochratoxin A appears in about half of samples, but usually far below EU limits (3.0 µg/kg roasted); roasting destroys 65–100%, and coffee is only ~9–10% of dietary intake.42,43 "Coffee is full of mould toxins" is overstated.

Which country drinks the most coffee?

Per person, Finland leads at roughly 12 kg per capita per year, followed by other Nordic countries and the Netherlands.49

Sources

References

Every statistic on this page traces to one of the peer-reviewed studies, regulatory documents or court/press records below. Where evidence is weak or a claim is disputed, the text says so.

  1. Poole R, et al. Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes. BMJ 2017;359:j5024. bmj.com
  2. Freedman ND, et al. Association of coffee drinking with total and cause-specific mortality. N Engl J Med 2012;366:1891. nejm.org
  3. Gunter MJ, et al. Coffee drinking and mortality in 10 European countries (EPIC). Ann Intern Med 2017;167:236. pubmed
  4. Grosso G, et al. Coffee consumption and mortality: dose-response meta-analysis. Eur J Epidemiol 2016;31:1191. pubmed
  5. Lovallo WR, et al. Stress-like adrenocorticotropin responses to caffeine in young healthy men. Pharmacol Biochem Behav 1996;55:365. pubmed
  6. Lovallo WR, et al. Caffeine stimulation of cortisol secretion across the waking hours. Psychosom Med 2005;67:734. PMC
  7. Lovallo WR, et al. Cortisol responses to mental stress, exercise, and meals following caffeine. Pharmacol Biochem Behav 2006;83:441. PMC
  8. Cohen S, Booth GH. Gastric acid secretion and lower-esophageal-sphincter pressure in response to coffee and caffeine. N Engl J Med 1975;293:897. nejm.org
  9. Feldman EJ, Isenberg JI, Grossman MI. Gastric acid and gastrin response to decaffeinated coffee and a peptone meal. JAMA 1981;246:248. pubmed
  10. Nehlig A. Effects of coffee on the gastro-intestinal tract: a narrative review. Nutrients 2022;14:399. PMC
  11. Klevebrant L, Frick A. Effects of caffeine on anxiety and panic attacks in panic disorder: meta-analysis. Gen Hosp Psychiatry 2021;74:22. doi.org
  12. Nardi AE, et al. Caffeine challenge test in panic disorder and depression. Depress Anxiety 2008;25:847. doi.org
  13. Childs E, et al. Association between ADORA2A/DRD2 polymorphisms and caffeine-induced anxiety. Neuropsychopharmacology 2008;33:2791. doi.org
  14. Hoppe JM, et al. Effects of 150 mg caffeine on anxiety in panic disorder: RCT. J Psychopharmacol 2025;39:836. doi.org
  15. Liu C, et al. Caffeine intake and anxiety: a meta-analysis. Front Psychol 2024;15:1270246. doi.org
  16. EFSA NDA Panel. Scientific Opinion on the safety of caffeine. EFSA Journal 2015;13:4102. doi.org
  17. Lucas M, et al. Coffee, caffeine, and risk of depression among women. Arch Intern Med 2011;171:1571. jamanetwork
  18. Wang L, et al. Coffee and caffeine consumption and depression: dose-response meta-analysis. Aust N Z J Psychiatry 2016;50:228. doi.org
  19. Grosso G, et al. Coffee, tea, caffeine and risk of depression: meta-analysis. Mol Nutr Food Res 2016;60:223. pubmed
  20. Lucas M, et al. Coffee, caffeine, and risk of completed suicide (3 cohorts). World J Biol Psychiatry 2014;15:377. PMC
  21. Torabynasab K, et al. Coffee, caffeine and depression: updated dose-response meta-analysis. Front Nutr 2023;10:1051444. doi.org
  22. Noordzij M, et al. Blood pressure response to chronic intake of coffee and caffeine: meta-analysis of RCTs. J Hypertens 2005;23:921. doi.org
  23. Mesas AE, et al. / EFSA. Caffeine and blood pressure: a critical review. Nutr Res Rev 2019. cambridge.org
  24. Xie C, et al. Coffee consumption and risk of hypertension: dose-response meta-analysis. J Hum Hypertens 2018;32:83. doi.org
  25. Zhang Z, et al. Habitual coffee consumption and risk of hypertension: meta-analysis. Am J Clin Nutr 2011;93:1212. doi.org
  26. Caldeira D, et al. Caffeine and risk of atrial fibrillation: meta-analysis. Heart 2013;99:1383. doi.org
  27. Kim Y, et al. Coffee consumption and all-cause and cause-specific mortality: meta-analysis. Eur J Epidemiol 2019;34:731. doi.org
  28. Teramoto M, et al. Coffee and green tea consumption and cardiovascular mortality among people with severe hypertension. J Am Heart Assoc 2022;11:e026477. ahajournals
  29. Ding M, et al. Caffeinated and decaffeinated coffee and risk of type 2 diabetes: dose-response meta-analysis. Diabetes Care 2014;37:569. doi.org
  30. Costa J, et al. Caffeine exposure and the risk of Parkinson's disease: meta-analysis. J Alzheimers Dis 2010;20:S221. doi.org
  31. Kennedy OJ, et al. Coffee, cirrhosis and liver disease: systematic review & meta-analysis. Aliment Pharmacol Ther 2016;43:562. doi.org
  32. Svilaas A, et al. Intakes of antioxidants in coffee, wine, and vegetables. J Nutr 2004;134:562. pubmed
  33. Mayo Clinic. Caffeine: How much is too much? (2025). mayoclinic.org
  34. U.S. FDA. Spilling the Beans: How Much Caffeine is Too Much? fda.gov
  35. ACOG. Moderate caffeine consumption during pregnancy (Committee Opinion 462). acog.org
  36. Mayo Clinic. Caffeine: How does it affect blood pressure? mayoclinic.org
  37. Harvard T.H. Chan School of Public Health. The Nutrition Source: Caffeine. hsph.harvard.edu
  38. Consumer Reports. Lead and cadmium in dark chocolate (2022). consumerreports.org
  39. In re Lindt & Sprüngli Dark Chocolate Litigation, No. 1:23-cv-01186 (E.D.N.Y. 2024) — order denying motion to dismiss. justia
  40. OEHHA. Cal. Code Regs. tit. 27 §25704 (2019) — coffee posing no significant risk. oehha.ca.gov
  41. CERT v. Starbucks Corp., 84 Cal.App.5th 879 (2022). justia
  42. Commission Regulation (EU) 2023/915 — maximum levels for contaminants (ochratoxin A). eur-lex
  43. Khaneghah AM, et al. Prevalence and concentration of ochratoxin A in coffee: meta-analysis. 2019. sciencedirect
  44. Clean Label Project. Coffee study — glyphosate/AMPA and heavy metals (2025). cleanlabelproject.org
  45. Quadram Institute / Univ. of East Anglia. Undeclared robusta in "100% Arabica" products. Food Chem 2018. sciencedirect
  46. U.S. Department of Labor. List of Goods Produced by Child Labor or Forced Labor — coffee (2024). dol.gov
  47. Repórter Brasil. Coffee and forced labour investigations (2025). reporterbrasil.org.br
  48. Daily Coffee News. Federal judge approves final $12M Kona coffee labelling settlement (2023). dailycoffeenews.com
  49. World Population Review. Coffee Consumption by Country (compiled from ICO / national data). worldpopulationreview.com
  50. Frigerio S, Strawbridge R, Young AH. The impact of caffeine consumption on clinical symptoms in patients with bipolar disorder: a systematic review. Bipolar Disord 2021;23(3):241–251. doi.org/10.1111/bdi.12990
  51. Rosen RL, et al. Caffeine levels and dietary intake in smokers with schizophrenia and bipolar disorder. Psychiatry Res 2022;319:114989. doi.org/10.1016/j.psychres.2022.114989
  52. Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37(5):348–350. doi.org/10.1016/0006-3223(94)00243-V
  53. Song JJ, Eyabi JC, Awatramani PD, et al. Sudden reduction in caffeine intake increases serum lithium concentration to supratherapeutic level: a case report. Prim Care Companion CNS Disord 2024;26(2):23cr03642. doi.org/10.4088/PCC.23cr03642
  54. Hägg S, Spigset O, Mjörndal T, Dahlqvist R. Effect of caffeine on clozapine pharmacokinetics in healthy volunteers. Br J Clin Pharmacol 2000;49(1):59–63. doi.org/10.1046/j.1365-2125.2000.00111.x
  55. Carrillo JA, Herraiz AG, Ramos SI, Benítez J. Effects of caffeine withdrawal from the diet on the metabolism of clozapine in schizophrenic patients. J Clin Psychopharmacol 1998;18(4):311–316. doi.org/10.1097/00004714-199808000-00011
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