As temperatures drop across Hong Kong, sparking the familiar quest for the ultimate warming beverage, a recent segment on the Japanese variety program Kono Sa tte Nandesuka? challenged conventional wisdom by scientifically testing popular hot drinks for their lasting thermogenic effects. The experiment results revealed that while many turn to ginger tea for a cozy heat boost, the beloved beverage only secured third place, prompting a reevaluation of which winter warmers truly battle the cold, particularly for those suffering from persistently cold hands and feet.
The television segment conducted a practical test on six common hot beverages: coffee, ginger tea, hot chocolate, green tea, black tea, and amazake (a traditional sweet, low-or non-alcohol Japanese drink made from fermented rice). Female participants, with an average baseline body temperature of 36.2°C, were monitored to determine which drink sustained an elevated body temperature for the longest period after consumption. The resulting ranking surprised many thermal traditionalists.
Unexpected Results in the Warmth Rankings
The highly anticipated champion for long-lasting warmth was amazake, suggesting that fermentation and its unique composition offer superior internal heat retention. While ginger tea proved effective, securing the third spot, other popular choices lagged significantly. Notably, hot coffee, often a daily staple, ranked last amongst the six tested beverages, demonstrating the shortest retention of heat in the body. Green tea came in fifth, highlighting that the immediacy of a hot drink doesn’t necessarily translate into sustained warmth.
Thermal Drink Ranking (Longest warmth retention):
- Amazake
- (Details omitted in source data)
- Ginger Tea
- (Details omitted in source data)
- Green Tea
- Coffee
Navigating the Calorie Content of Comfort Drinks
The pursuit of warmth often overlaps with the indulgence of comfort, leading consumers to high-calorie hot beverages. Alongside the warmth ranking, an analysis of the calorie content in common winter drinks serves as a crucial reminder for health-conscious individuals. Many favourites, while visually appealing and comforting, pack a significant caloric punch.
Drinks frequently found among the top ten highest in caloric value included creamy options like hot chocolate and malted beverages such as Horlicks and Ovaltine. The most calorific offering detailed in the analysis was reported to contain six times the heat content of an espresso, equating roughly to 0.7 bowls of white rice, and dangerously close to half the daily recommended sugar intake limit. Conversely, simple infusions and unsweetened teas, such as green tea or those lower on the list like lemon tea (20th) and watercress honey (18th), generally offer far lower energy content.
Key takeaways for consumers include exercising caution with drinks high in sugar and fat:
- Top Calorie Culprit: Highest-ranking drink on the calorie list (unspecified)
- Third Highest: Hot Chocolate drinks
- Sixth Highest: Ovaltine
- Tenth Highest: Horlicks
Safety Considerations for Warm Beverage Containers
Beyond the contents, the safety of the vessel used to keep drinks warm should not be overlooked. Experts caution users on the potential for harmful chemical leaching from poorly manufactured thermos flasks and containers.
Both stainless steel and plastic options carry inherent risks. Plastic containers should be checked for the recycling code—ideally marked with “5” (PP) or “7” (PC)—indicating high durability and temperature resistance (up to 130-140°C). Products labeled “3” (PVC) have lower heat thresholds (around 80°C), risking plasticizer release when filled with very hot liquids.
For stainless steel flasks, consumers must ensure they are made from food- or medical-grade steel, specifically grades “304” or “316”. Lower-grade, industrial-use “200” series stainless steel is prone to corrosion and can leach heavy metals like manganese, which, in excess amounts, pose risks to brain health.
These insights underscore the importance of mindful consumption and material selection, ensuring that the act of staying warm this winter is both effective and safe for long-term health. Individuals experiencing persistent cold sensitivity are encouraged to explore alternative options like amazake as a potentially more effective thermal aid.