Hot Beverage Temperature — Body Handbook

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Hot Beverage Temperature

The drink temperature most people accept as "normal hot" — the first sip from a fresh cup of coffee or tea — is hot enough that the World Health Organisation's cancer agency classifies it as a probable cause of esophageal cancer. The threshold is roughly 65°C, and a tea or coffee poured at boiling stays above it for the first three to five minutes. The fix is the cheapest intervention in this catalogue: wait, or add a splash of cold. What follows is what the evidence actually says, who carries the most risk, and how to stop without giving up a single hot drink.

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The cancer this is about — esophageal squamous cell carcinoma — is rare in most Western countries but one of the deadliest when it happens; five-year survival sits near 20%. The relative risk for the typical reader is modest. For a smoker or heavy drinker the same hot cup multiplies an already-real risk by another factor of two to five. And unlike most cancer-prevention moves, this one costs nothing — no money, no willpower, no giving anything up. You're just trading the first scalding sip for the second, slightly cooler one.

The lining of your esophagus is a thin layer of squamous cells — the same family as the cells in your mouth and skin — built to handle abrasion but not to handle being repeatedly cooked. Above about 60°C, proteins start to denature; above 65°C, the cells begin to die. Swallow a sip at 70°C and the drink only cools by a few degrees on the way down, so the upper and middle parts of your esophagus take the brunt of it. Each individual scald heals in days. The problem is the repetition.

Chronic injury anywhere in the body follows the same pattern: damaged cells get replaced, replacement means more cell divisions, more cell divisions mean more chances for a copying error to stick. After enough years, one of those errors becomes a tumour. This is the same chain that ties smoking, heavy drinking, and acid reflux to their respective cancers — an irritant the body keeps trying to repair until the repair machinery itself goes wrong Abnet 2018.

What the cohorts actually show

The strongest evidence comes from three completely different parts of the world that all drink hot things and all happen to have well-run long-term cohorts. The findings line up.

The China Kadoorie Biobank, with about 456,000 adults followed prospectively, surfaced a finding that matters more than the Iran numbers do for the rest of us. Hot tea on its own — in non-smokers who didn't drink much alcohol — didn't show an independent cancer signal. But hot tea combined with daily alcohol use carried a hazard ratio of 5.0; combined with current smoking, it was 2.0 Yu et al. 2018. Thermal injury, in that population, looked less like a stand-alone carcinogen and more like an amplifier for tobacco and alcohol.

And South America, where mate is drunk near boiling through a metal straw, gives the third leg. A pooled analysis of case-control studies across Argentina, Brazil, and Uruguay found hot mate roughly doubled esophageal cancer risk; cold mate showed nothing Lubin et al. 2014. Different beverage, different chemistry, same temperature signal.

Stitched together — plus a 39-study meta-analysis pooling the global literature at relative risk around 1.6 for the hottest temperature category Andrici & Eslick 2015 — this is what put very hot beverages into the same World Health Organisation cancer category as red meat and night-shift work. The evidence isn't a single landmark trial. It's the same pattern showing up everywhere the question gets asked.

What's actually at stake

For most readers in most Western countries, the cancer this is about is uncommon. Esophageal squamous cell carcinoma runs at fewer than five new cases per hundred thousand people per year in North America and Western Europe — ten to twenty times lower than in the Iranian and Chinese cohorts where the strongest evidence comes from. The absolute risk you're reducing by giving up scalding sips is small.

But it's not zero, and the cancer itself is brutal. Esophageal cancer is the kind that shows up as trouble swallowing — food sticking, weight loss, by which point it's usually advanced. Five-year survival across all stages sits near 20%; treatment is some combination of esophagus-removing surgery, chemotherapy, and radiation, and the people who do survive often eat differently for the rest of their lives GBD 2017 Oesophageal Cancer Collaborators 2020. Worldwide, it kills about 540,000 people a year — more than cervical cancer.

The two readers who should care most:

Anyone who smokes or drinks heavily. Hot tea and heavy alcohol multiply each other's risk — not add. Five times the baseline rate for the combination, two times for smoking alone with hot tea Yu et al. 2018. If you're already in one of those columns, the cheapest move you can make is the temperature one.
Anyone with elevated baseline esophageal risk. Barrett's esophagus, a family history of esophageal cancer, prior chest radiation, head-and-neck cancer in your past, achalasia. Same logic: the temperature is one input you can take off the table for free.

For everyone else, this is cheap insurance against a low-probability bad outcome. The math doesn't say "you're going to get cancer if you drink hot tea." It says: across a population of millions, the people who drank everything scalding got the disease at a higher rate, the dose-response was clean, and the intervention to opt out of that group costs nothing.

How to actually stop

The target is the first sip at under 60°C — comfortably below the World Health Organisation's threshold and around where most people stop describing a drink as "hot" and start describing it as "warm." A ceramic mug of fresh tea or coffee poured at boiling cools to that range in roughly four to six minutes at normal room temperature. A travel mug or a thermos can hold it dangerously hot for half an hour or more — that's the failure case.

The lazy version of all of this: stop sipping the second you pour. The first sip is the one that does damage. Get into the habit of pouring and walking away, and the rest takes care of itself.

What most coverage of this gets wrong

"Hot tea is healthy — tea is healthy." Tea drunk warm or cold seems to do you a small favour, by way of catechins and other polyphenols. Tea drunk scalding does the opposite. The chemistry is one thing; the temperature is another. You can have the catechins without the burn — pour, wait, drink.
"Coffee causes cancer." Coffee itself spent 25 years in the World Health Organisation's "possibly carcinogenic" bucket. In 2016 it was let out, specifically because once the agency separated temperature from chemistry, the chemistry came back clean Loomis et al. 2016. Iced coffee, cold brew, warm coffee — not the problem. The first scalding sip is.
"If it doesn't burn my mouth, it's fine." Your oral mucosa starts hurting around 70°C. The cancer-relevant threshold is 65. A sip that feels hot but tolerable can still be above the line.
"The studies are from Iran and China — that's not me." The relative-risk findings replicate across very different populations, including South American mate drinkers. What changes between populations is the absolute risk you're reducing, which is much smaller for a non-smoking, non-drinking reader in a low-incidence country. The biology of cooking your esophagus does not, however, get a regional exemption.

Where this goes wrong in practice

The honest failure mode isn't "the science was wrong" — it's that the modern coffee-shop industry, the insulated-mug industry, and the way most people drink in a hurry all conspire to keep the cup in the danger zone.

Insulated travel mugs and thermoses. Built to hold heat. A vacuum-insulated stainless cup can keep a drink near pouring temperature for half an hour or more — meaning every sip is the "first sip," and every one is above threshold.
Drive-through and to-go coffee. Specified serving temperatures at most major chains land between 65 and 80°C. The cup is engineered to keep that heat. You're meant to drink it walking, which means the first sip is hot enough to burn — that's not an accident, it's the product.
"Extra hot" orders. The same chains will heat a drink to ~75°C+ on request. It comes out actively dangerous and stays that way for longer.
Sipping while distracted. The reflexive ritual of pouring a fresh cup and immediately sipping while reading or replying to a message. The drink is at its hottest in those first ninety seconds; the body's pain warning isn't the same as the tissue-damage warning.
Cultural defaults. Strong tea drunk immediately after brewing — standard in much of the world — is precisely the high-risk pattern the Golestan and Kadoorie cohorts identified Yu et al. 2018, Islami et al. 2020. The behaviour is so normalised that it doesn't feel like a risk factor.

What you actually get

This is the most uneventful payoff in the catalogue. You don't feel different. Your morning doesn't change. You don't notice anything in a week, or a month, or a year.

What you get is a probability. The version of you that drinks scalding cups every morning for the next thirty years is, in expectation, more likely to be the one who finds out about esophageal cancer at age 64 than the version that waits four minutes. You won't know, individually, which version you ended up being. Nobody will tell you "I noticed you look healthier" because you started drinking your coffee at 60°C instead of 80. The decade in which the disease tends to show up will arrive, and nothing in particular will happen.

That's the entire point. The catalogue is full of interventions that pay back in sleep quality next week, mood next month, energy next year. This one pays back in a thing that doesn't happen. Treat it the way you treat seat belts: cheap, unobtrusive, no felt benefit on any given day, real benefit at the timescale your body actually operates on.

The one exception — the people who do get a felt payoff — are habitual scalding-sippers who have been quietly putting up with mouth and throat soreness for years. That goes away within days. It's not the reason to do this, but it's the only short-term signal the body sends.

Adjacent topics worth knowing about:

Alcohol and cancer risk. The most important co-exposure for this one — the temperature signal multiplies whatever alcohol is already doing.
Smoking. Same logic. The combination is what produces the highest hazard ratios in the cohort data.
Barrett's esophagus and reflux. A different esophageal cancer pathway (adenocarcinoma, acid-driven, not heat-driven), with its own playbook.
Esophageal cancer screening. There is no general-population screening recommendation; high-risk patients have specific endoscopic surveillance protocols their gastroenterologist will set.

დაკავშირებული სახელმძღვანელოში

დაკავშირებული

— For a heavy drinker, the same scalding cup multiplies an already-real esophageal cancer risk.
— Very hot drinks and the alcohol-flush gene both raise esophageal cancer risk; the two compound.
— The risk is the heat, not the coffee — let that morning cup cool a few minutes before the first sip.
— Both quietly injure the same esophageal lining — scalding sips from the top, acid from below — so it's worth easing off both.
— In a smoker, a scalding daily cup multiplies the esophageal cancer risk smoking already carries.

Substance and claimed effects

The substance is the act of swallowing drinks at temperatures above roughly 65°C — the temperature threshold that the International Agency for Research on Cancer adopted in 2016 when classifying "drinking very hot beverages" as Group 2A: probably carcinogenic to humans for esophageal cancer Loomis et al. 2016, IARC Monograph Vol 116. The cancer at issue is esophageal squamous cell carcinoma (ESCC), the histology that dominates in the high-incidence belt (Iran, Central Asia, China, parts of East Africa, southern South America) and that is biologically downstream of chronic mucosal injury rather than chronic acid reflux Abnet 2018. ESCC is highly lethal: 5-year survival is approximately 15–25% globally GBD 2017 Oesophageal Cancer Collaborators 2020. Claimed mechanism: repeated thermal injury to the squamous epithelium drives chronic inflammation, accelerated cell turnover, and accumulated mutations. The entry covers longevity (cancer risk — the load-bearing dimension), short-term health (acute mucosal injury, mouth/throat scalds, possible aggravation of reflux), and effort burden (the cost of waiting 3–5 minutes). It also covers the evidence and controversy axes because IARC 2A is a contested category — the same tier that holds glyphosate and night-shift work.

Evidence by addressing question

mechanism

Esophageal squamous epithelium is constantly exposed to swallowed material; temperature is the variable the body can least afford. Acute thermal injury above ~60°C produces protein denaturation and visible mucosal damage; in animal models, repeated hot-water gavage produces hyperplasia, parakeratosis, and basal-cell proliferation, with synergistic effects when paired with N-nitrosamines IARC 2018. The chronic-inflammation-to-cancer chain is well established for ESCC across other exposures (smoking, alcohol, hot food, opium): persistent epithelial injury → reactive cell turnover → accumulated DNA damage → squamous dysplasia → invasive carcinoma Abnet 2018. The temperature gradient down the esophagus also matters: thermometry studies show drinks cool by only a few degrees during swallowing, so a sip at 70°C still hits the upper- and mid-esophageal mucosa near that temperature.

The mechanism is biologically supported but not as cleanly proven as for chemical carcinogens. IARC's 2A call was driven primarily by animal evidence of thermal injury and consistent epidemiology, with explicit acknowledgement that the underlying mechanism is repeated mucosal injury rather than a specific chemical species Loomis et al. 2016.

evidence

The epidemiological signal is replicated across geographies, cultures, and beverage types:

Golestan, northern Iran (case-control, 2009). 300 ESCC cases vs 571 controls. Drinking tea "very hot" (vs "warm/lukewarm") carried an odds ratio of 8.16 (95% CI 3.93–16.9); drinking within <2 minutes of pouring vs >4 minutes carried OR 5.41 Islami et al. BMJ 2009. The extreme effect sizes reflect a high-incidence population (Iran lies on the "esophageal cancer belt").
Golestan Cohort Study (prospective, ~50,000 adults). Drinking ≥700 mL/day of tea at ≥60°C was associated with HR 1.90 for ESCC vs <700 mL/day at <60°C; the temperature-volume interaction was dose-dependent Islami et al. Int J Cancer 2020.
China Kadoorie Biobank (prospective, ~456,000 adults). Burning-hot tea alone showed modest HR for ESCC (~1.0–1.3 across categories); the load-bearing finding was the multiplicative interaction: hot-tea drinkers who also drank ≥15 g alcohol/day had HR 5.0, and current-smoking hot-tea drinkers had HR 2.0 Yu et al. Ann Intern Med 2018. Hot tea without alcohol or smoking did not show an independent ESCC effect in this cohort — an important boundary finding.
South American mate studies. Pooled case-control data (~1,400 ESCC cases, ~3,900 controls across Argentina, Brazil, Uruguay) showed mate drinking at high temperatures roughly doubled ESCC risk (OR ~2.0); cold mate did not Lubin et al. 2014. Different beverage, different polyphenol profile, same temperature signal.
Meta-analyses. Andrici & Eslick (39 studies) found RR 1.6 for highest vs lowest temperature category for esophageal cancer Andrici & Eslick 2015. Chen et al. (40 studies) reached comparable pooled estimates with consistent direction Chen et al. 2015.
Historic anchor. Singapore Chinese case-control (1972) was an early Western-published signal: hot beverage and food consumption tied to esophageal cancer in a non-Iranian population De Jong et al. 1972.

The IARC working group reviewed this literature plus the animal evidence and assigned Group 2A: limited evidence in humans, sufficient evidence in animals, no specific chemical implicated (the agent is the temperature) Loomis et al. 2016, IARC 2018. Coffee was simultaneously moved from Group 2B (possibly carcinogenic) to Group 3 (not classifiable) — the chemistry of coffee per se was exonerated; only the temperature carries risk.

protocol

The IARC threshold is 65°C, derived from the published literature where measurable risk emerged. Brown & Diller's thermal modeling found that the temperature at which a swallow stays brief enough to avoid mouth-pain (and at which serving-related scald risk drops) is around 57–58°C for oral comfort Brown & Diller 2008. A practical target is <60°C at first sip — below the IARC threshold with margin.

Real-world cooling: a 250 mL ceramic mug of tea or coffee at 85°C cools to 65°C in roughly 4–6 minutes at room temperature; an insulated/thermos vessel can hold beverages near serving temperature for 30+ minutes. A 30–50 mL splash of room-temperature water or milk drops a typical mug by 5–10°C immediately. Specialty "optimum-temperature" mugs and most stainless-steel insulated cups are the principal failure mode: they preserve the danger range.

contraindications

The intervention is "wait a few minutes"; there are no contraindications. The relevant medical conditions are amplifiers, not restrictions: people with Barrett's esophagus, prior chest radiation, achalasia, head-and-neck cancer history, or known ESCC risk factors (heavy alcohol, smoking, family history, opium use) have higher baseline risk and benefit more from the same change.

misconceptions

Three are common:

"Hot tea is healthy because tea is healthy." Conflates the chemistry (catechins, polyphenols — protective in observational data) with the temperature (carcinogenic). Iced or warm tea preserves the chemistry without the thermal injury Loomis et al. 2016.
"Coffee causes cancer." The 1991 IARC 2B coffee classification was reversed in 2016 specifically because once temperature was separated out as the carcinogen, coffee itself fell to Group 3 Loomis et al. 2016. The same applies to mate — cold mate is not implicated.
"If it doesn't burn my mouth it's fine." The pain threshold for oral mucosa is around 70°C; the cancer-relevant threshold is 65°C. A drinkable-by-feel sip can still be above the IARC threshold.

audience

Effect size scales with baseline ESCC risk:

High-incidence populations (Iran, Central Asia, parts of China, parts of East Africa, southern South America). ESCC is among the top cancers; the temperature signal is strongest and the absolute risk reduction largest.
Smokers and heavy drinkers. Multiplicative interaction: hot tea + heavy alcohol HR ~5 in China Kadoorie Yu et al. 2018.
Low-incidence populations (Western Europe, North America, Australia). Adenocarcinoma dominates and is reflux-driven rather than thermal; ESCC absolute rates are low. The relative risk persists but the absolute risk reduction is small.

practicalities

Most coffee shops serve at 70–85°C (Starbucks' specified service temperature is ~71°C / 160°F for "extra hot" and ~65–71°C standard; McDonald's coffee-burn litigation drove industry-wide attention to this range). Tea brewed with boiling water (100°C) is fully within the danger zone for several minutes. Real-world serving practice is the failure mode — the typical reader's beverage is dangerous in the first 3–5 minutes after pour and safe thereafter.

stakes

ESCC globally accounts for ~85% of esophageal cancer cases (~604,000 new cases and ~544,000 deaths in 2020) GBD 2017 Oesophageal Cancer Collaborators 2020. Population-attributable fraction for very hot beverages in high-incidence regions has been estimated at 20–40% of ESCC cases; in low-incidence regions it is likely <5% but non-zero. The disease itself is dysphagia → weight loss → esophagectomy or palliation; 5-year survival ~15–25%.

payoff

Stopping very-hot drinking removes one mucosal-injury input. There is no felt-experience payoff — the mucosa heals silently within days, and the risk reduction is a probabilistic delta against a low-base-rate cancer. The honest framing is "cheap insurance," not "you will feel better next week." The relative-risk reduction may take decades to manifest in the population's incidence curves and is unobservable at the individual level.

out-of-scope

Adjacent topics this entry should signpost: esophageal cancer screening (no general-population screening; high-risk only), Barrett's esophagus (a different cancer pathway — adenocarcinoma, acid-driven), GERD, alcohol and cancer risk, smoking and cancer risk.

The credibility range

Optimist case

The evidence is unusually broad for a non-pharmaceutical exposure. Effect direction is consistent across the Iranian, Chinese, South American, and (older) Singapore Chinese cohorts; the dose-response on temperature is monotonic; the mate evidence triangulates from a different beverage chemistry; mechanism is biologically plausible and animal-supported; IARC — the most cautious expert body on carcinogen classification — placed the exposure at 2A, the same level as red meat and shiftwork. Multiplicative interaction with tobacco and alcohol fits the chronic-injury model. The intervention is zero-cost and reversible; even modest relative-risk reduction multiplied across a billion daily hot drinks worldwide is a meaningful public-health quantity.

Skeptic case

Most strong-effect studies come from high-incidence regions where ESCC has multiple co-occurring risk factors — opium use in Iran, nutritional deficiencies, specific tobacco preparations, low fruit/vegetable intake. Residual confounding is hard to fully exclude with self-reported beverage-temperature recall. The Yu et al. 2018 finding that hot tea showed no independent ESCC effect in non-smokers and non-drinkers raises the possibility that the "very hot beverage" signal is really a tobacco/alcohol effect amplified by thermal co-exposure rather than a stand-alone carcinogen Yu et al. 2018. IARC 2A is a broad category (also includes glyphosate, night-shift work, very hot beverages) and overstates certainty for general readers. In Western populations, where ESCC incidence is <5 per 100,000 and adenocarcinoma dominates, the absolute risk attributable to drinking temperature is small enough that ordinary measurement noise (self-reported recall, residual confounding) can plausibly produce the observed effect.

Author's call

The thermal-injury → ESCC mechanism is real and the dose-response in heavy-exposure populations is too consistent to dismiss as confounding. In low-incidence Western populations the independent effect on a non-smoker, non-heavy-drinker reader is probably modest — possibly within noise — but non-zero. The intervention cost is so close to zero that even a small expected benefit dominates. Score evidence at 4 (replicated across geographies, mechanism-supported, guideline-backed by IARC, but no RCT and the Western-population estimate is fuzzy), longevity at 2 (small additive effect on mortality risk for the typical reader, larger for smokers/heavy drinkers and in high-incidence regions), controversy at 2 (Yu et al.'s independent-null result, IARC-2A breadth, and Western population effect-size uncertainty are real, but the substance is not a battleground).

Stakeholder and incentive map

IARC and cancer-research bodies. Strong public-health incentive to flag preventable exposures; classification methodology is conservative and reproducible.
ESCC researchers in high-incidence regions (Iran's Golestan, China's Linxian). Long-running cohorts; deep institutional knowledge; the temperature signal is one of several they have surfaced.
Tea, coffee, mate industries. Limited active pushback on the temperature finding specifically — the 2016 reclassification arguably helped the coffee industry (downgrading coffee itself from Group 2B). The mate industry in southern South America has cultural incentive to defend hot consumption.
Coffee-shop / quick-service industry. Post-McDonald's-burn-litigation, service temperatures have been studied and standardised; commercial incentive is for hot service (perceived freshness, longer drinkability window).
Counter-incentive: dietary skeptics, IARC critics. Argue IARC 2A overweights animal evidence and conflates probabilistic carcinogenicity with practical risk.

Population variability

Baseline ESCC incidence. Iran (Golestan): age-standardised ESCC incidence >40 per 100,000 in some sub-populations. Western Europe / North America: ESCC incidence <5 per 100,000. Same relative risk, ~10× the absolute risk reduction in the high-incidence setting.
Smoking and alcohol status. Hot tea + heavy alcohol HR ~5.0 in China Kadoorie; the same hot tea in non-smokers/non-drinkers showed no independent effect in that cohort Yu et al. 2018. The clearest beneficiaries of the intervention are smokers and heavy drinkers.
Cultural drinking patterns. Iranian tea is typically drunk immediately after brewing; British/American tea typically rests with milk; Japanese green tea is brewed at ~70°C and served cooler. The hazard is in when and how, not the beverage chemistry.
Existing mucosal vulnerability. Barrett's, prior radiation, achalasia, head-and-neck cancer survivors, tylosis (rare genetic predisposition) all raise baseline ESCC risk; the temperature input matters more.
Age. ESCC is largely a disease of adults ≥50; cumulative exposure matters, so the relevant timescale of behavior change is decades.

Knowledge gaps

Exact threshold. The 65°C number is a working IARC cut-point derived from the available studies; the true dose-response is probably continuous. Whether 60°C is meaningfully safer than 64°C is unresolved.
Western-population effect size. Almost all the strongest studies are from high-incidence regions. The independent effect on a non-smoking, non-heavy-drinking Western reader is poorly characterised.
Coffee vs tea vs mate at matched temperatures. IARC's framing is that temperature is the carcinogen and chemistry is incidental, but no head-to-head trial compares matched-temperature exposures across beverages. The implicit prediction (equivalent risk at equivalent temperature) is consistent with the data but unproven.
Microbiome and barrier effects. Whether hot beverages alter the esophageal microbiome or barrier function in ways that compound the thermal effect is an active research area.
RCT impossibility. Decades-to-cancer outcomes, low base rates in many regions, and ethical considerations make a randomised trial impractical. Future evidence will come from cohorts (the Golestan and Kadoorie biobanks will continue producing data) and from biomarker work (mucosal biopsy, dysplasia incidence) as proxies.

Scope. The brief asked for esophageal mucosal injury and esophageal cancer risk per the IARC classification; the article covers both, treating mucosal injury as the mechanism layer and cancer risk as the load-bearing reason to act. The temperature threshold and IARC's 2A call are the spine.

Longevity score = 2, not 3. This was the hardest call. The relative risk is well-replicated and the cancer is highly lethal, but for the typical reader of this catalogue (non-smoker, low-to-moderate drinker, low-incidence region) the absolute risk reduction is small. Yu et al. 2018's finding that hot tea showed no independent ESCC effect in non-smokers/non-drinkers in the China Kadoorie cohort is the strongest reason not to score higher; a 3 ("meaningful disease-prevention") would overstate the typical-reader payoff. The score reflects the substance's holistic effect across populations, with a larger payoff for smokers/heavy drinkers and high-incidence-region readers explicitly framed in the article's stakes and audience material.

Controversy = 2. Not high — IARC's call is solid and replicated — but the Western-population effect-size question is genuinely open and IARC 2A's breadth (glyphosate, shift work, very hot beverages all share a bucket) is a fair critique. Wanted to mark this honestly rather than score 1 and pretend it's settled.

Evidence = 4. No RCT exists and none can; the score reflects converging large-cohort evidence across geographies plus animal-model mechanism support. Held back from 5 because the cleanest Western-population estimates are still missing.

health_short_term = 1. Acute mucosal injury is real but the day-to-day felt experience of switching is genuinely subtle for most people. Considered 0; landed on 1 because chronic mouth/throat soreness in habitual scalding-sippers does resolve.

Audience not narrowed. Considered scoping by gender (ESCC is more common in men) but the intervention is universal and the audience-scoping field is for cases where the substance doesn't apply, not for cases where incidence differs. Article's audience-adjacent content lives inside the stakes section instead, because the population-variability story is part of why the reader should care.

Excluded. Hot food (rather than beverages) has overlapping evidence but a different exposure profile (less of the swallow stays at peak temperature); a separate entry would be a candidate if the catalogue wants it. Coffee chemistry (caffeine, polyphenols) is deliberately left to a future coffee entry — this entry is about temperature, not the drink.

Future-link candidates. When entries exist: alcohol-and-cancer-risk, smoking, barretts-esophagus, gerd. The out-of-scope section already signposts these as topics; the actual related meta field is left empty until those ids exist.

Separate-entry candidates. Hot-food temperature (overlapping but distinct exposure). Esophageal cancer screening for high-risk patients (clinician-mediated, decide-action, distinct topic). Mate-specific cancer risk probably not warranted as a separate entry — it's a culturally specific instance of this same substance.