Why You Should Avoid Drinking Coffee During Dangerous Heat Waves

During a heatwave, you may find yourself seeking out your most comforting daily habits to help your body adjust to the scorching heat and high humidity. But some of them can work against you in extreme temperatures — if you love spicy foods, you shouldn't steer clear of them during a heatwave, as the sweat they produce can cool you down. But what about coffee? Many of us start our days with a cup, but experts say you should think twice about having one when heatwaves create dangerous temperatures.

Health advisories are typically issued when temperatures and heat index values exceed normal ranges — conditions that increase the risk of dehydration and heat-related illness. According to the Centers for Disease Control and Prevention (CDC), you should avoid beverages that are high in caffeine, such as coffee and some brands of tea. Caffeine is a mild diuretic that can increase urine output, which can in turn accelerate dehydration. 

Drinking coffee in extreme conditions like that of a heatwave can cause you to suffer severe fluid loss or dehydration, especially since you're also most likely sweating profusely during the high temperatures. Symptoms of dehydration include dizziness, confusion, and dark-colored urine, and can lead to heat exhaustion or heat stroke, loss of consciousness, and even seizures. 

According to science, the best time to drink coffee is in the morning (though drinking a cup of coffee at night isn't so strange). But when it's extremely hot outside, it's best to forgo your usual caffeine routine to remain hydrated throughout the day. However, it's not just coffee that experts have warned against drinking during extremely hot weather conditions. The CDC, for one, has also encouraged limiting the intake of alcohol and drinks high in sugar and sodium. Like coffee, these can also cause you to lose more body fluid. Alcohol is also a diuretic and triggers the body to excrete more urine. On the other hand, drinks high in sugar and sodium draw water from the body to help flush out these elements, which can result in serious problems like hypertension,

So what is the best drink to beat the heat? Experts say that plain water is still the most effective beverage to keep your body hydrated, and it doesn't matter if the water's warm or cold. "When you drink cold water, your body naturally warms it up. If you prefer cold drinks, add ice. However, it won't internally make a difference," Applied Human Nutrition Professor Dr. Jennifer Brady explained in a Mount Saint Vincent University press release. This gentle reminder can make a big difference and even save lives, especially in the middle of a dangerous heatwave.