The Initial Shock of 'Too Hot'
The oesophagus, the muscular tube connecting your throat to your stomach, is lined with delicate tissue. When you swallow a liquid that's excessively hot—generally considered to be above 65°C—it causes immediate thermal injury. Think of it as a mild,
internal burn. Symptoms might not always be obvious, but can include chest pain, difficulty swallowing (dysphagia), or pain while swallowing (odynophagia). In some cases, endoscopy reveals visible damage, such as redness, erosions, and the formation of a whitish layer called a pseudomembrane, as the body reacts to the injury. Some doctors even describe a distinctive “candy cane” appearance, with alternating red and white bands in the oesophageal lining.
A Cycle of Damage and Repair
A single instance of drinking something too hot is unlikely to cause lasting harm, as the tissue is capable of healing. The real problem arises from repetition. If you consistently drink scalding beverages day after day, you subject your oesophagus to a state of chronic injury. This forces the cells in the lining to constantly repair and replace themselves. This endless cycle of damage and regeneration is a state of chronic inflammation. Instead of fully healing, the tissue remains in a reactive state, which over the long term, can lead to more profound structural changes.
How Healthy Tissue Begins to Change
Under the stress of chronic inflammation, the very structure of the oesophageal tissue can begin to alter. The constant need for cell division to replace damaged cells increases the chances of errors occurring during DNA replication. This rapid turnover can lead to abnormal cell growth. The theory is that this repeated thermal injury can impair the protective barrier function of the oesophageal lining. This makes the tissue more vulnerable not only to the heat itself but also to other potential carcinogens from diet or the environment, like those from alcohol or tobacco.
The Link to Oesophageal Cancer
This pathway from thermal injury to cellular alteration is a significant concern because it is linked to an increased risk of a specific type of cancer: oesophageal squamous cell carcinoma (SCC). In 2016, the International Agency for Research on Cancer (IARC), a branch of the World Health Organization, classified drinking beverages hotter than 65°C as "probably carcinogenic to humans". It is crucial to note that the risk is associated with the temperature, not the beverage itself—whether it's tea, coffee, or another drink. This type of cancer is more prevalent in parts of Asia, South America, and Africa, where consuming very hot drinks is a cultural norm. While other factors like smoking and alcohol are major causes of oesophageal cancer, chronic thermal injury is now recognised as a significant, independent risk factor.
A Simple Change for Safer Sipping
The good news is that this risk is entirely preventable with a simple behavioural change. The key is to let your hot beverages cool down before you drink them. There’s no need to give up your favourite tea or coffee, just the habit of drinking it at scalding temperatures. Experts suggest waiting a few minutes after pouring. If a drink is too hot to hold comfortably or if the steam is excessive, it’s likely too hot to drink. Aim for a temperature that is warm or comfortably hot, not burning. Studies have shown that even this small adjustment can significantly lower your risk, especially since many people in India have a cultural affinity for very hot chai. By being mindful of the temperature, you can continue to enjoy your daily ritual without compromising your long-term health.
