The Link Between Heat and Health
The central finding causing this stir comes from the World Health Organization's International Agency for Research on Cancer (IARC). After reviewing numerous studies, the IARC classified drinking "very hot" beverages as "probably carcinogenic to humans".
The research points specifically to an increased risk of esophageal cancer. It’s crucial to understand that the risk is not tied to the coffee or tea itself—which were not found to be carcinogenic—but is instead linked directly to the temperature at which any beverage is consumed. This finding has been consistent across studies in various parts of the world where consuming extremely hot drinks is traditional, including regions in Asia, South America, and Africa.
How Hot Is Actually Too Hot?
So what does "very hot" mean in practical terms? The scientific consensus pinpoints the danger zone as any beverage consumed above 65°C (149°F). For context, many cafes serve coffee at temperatures between 71°C and 85°C, well above this threshold. While most people find temperatures above 65°C uncomfortably hot and would naturally wait, the habit of sipping a drink immediately after it's been prepared with boiling water can expose you to these risky temperatures. Studies suggest an optimal drinking temperature, which balances flavour and safety, is closer to 58°C (around 136°F), a temperature that is pleasantly warm without posing a scalding risk.
Understanding the Damage
The danger from scalding drinks isn't chemical, but physical. It's a matter of repeated thermal injury. Think of it like a persistent burn. When you repeatedly consume liquids hot enough to scald the delicate cells lining your esophagus, you cause chronic inflammation and cellular damage. Over time, the body’s constant cycle of repair can go awry, potentially leading to the development of cancerous cells. This process explains why the risk is associated with long-term, regular consumption of very hot drinks rather than an occasional hot sip. While the overall risk for esophageal cancer remains relatively low for many populations, this repeated thermal injury is a significant contributing factor, especially when combined with other risks like smoking and alcohol consumption.
Simple Steps for Safer Sipping
The good news is that mitigating this risk requires only a minor adjustment to your routine. The solution is simple: patience. Instead of drinking your tea or coffee the moment it’s poured, let it cool for a few minutes. How long? While there’s no magic number, waiting 5 to 8 minutes can often bring a freshly brewed drink down to a safer temperature below 60°C. You can also add a splash of cold milk or water, or transfer the beverage between mugs to speed up the cooling process. The easiest rule of thumb is to take a small, tentative sip first. If it feels uncomfortably hot on your lips or tongue, it's definitely too hot for your esophagus. Waiting until it's comfortably warm won't just protect your health, but many connoisseurs argue it also improves the flavour, as extreme heat can overwhelm your taste buds.
