Bengaluru: Walk down almost any street in Bengaluru today and chances are you’ll find a coffee shop packed with people working on laptops, catching up with friends or queuing up for a cup of the city’s latest viral brew. In a city where a new café seems to open every week, coffee has become more than a beverage — it’s a lifestyle. But behind the frothy lattes and aesthetic cappuccinos, doctors are seeing a quieter trend brewing: a growing number of people whose bodies simply aren’t handling all that caffeine.“Bengaluru’s surging café culture has driven a noticeable rise in OPD visits due to overconsumption of caffeine. We usually treat around 15 to 20 patients monthly for caffeine-related issues, primarily affecting IT and startup professionals aged 22 to 38,” said Dr M Ravi Kumar, senior consultant, internal medicine, Sakra World Hospital.According to him, some patients walk in with persistent acidity and acid reflux caused by excess gastric acid secretion. Others struggle with anxiety, tremors and sleeplessness, while some experience sudden heart palpitations. Headaches, excessive sweating and dizziness are also commonly reported.Experts stress that coffee itself is not the villain. Explaining its benefits, Dr Kumar said, “Consuming black coffee delivers notable metabolic, cognitive, and neuroprotective health benefits by supplying rich antioxidants without added sugars or fats. It enhances focus, lowers the risk of type 2 diabetes, and protects vital organs like the liver and brain from chronic deterioration.”The real issue lies in how much and when people consume it, and how their bodies process caffeine. “There is a noticeable rise in individuals consuming multiple cups of coffee throughout the day. For most people, coffee is not harmful when had in moderation and may even have some health benefits. However, susceptible individuals may experience adverse symptoms when they consume excessive amounts, or consume it frequently, especially in combination with energy drinks, poor sleeping habits, long working hours and high stress levels,” said Shalini Arvind, chief dietitian, Fortis Hospital, Bannerghatta Road.Why does coffee affect some more than others?According to experts, the caffeine intake per day should be under 400mg. This could mean about four cups of brewed coffee (95mg a cup), about six shots of espresso (63mg per shot), or around 2.5 cups of a large latte (around 160mg each).Caffeine works by blocking adenosine receptors in the brain — the chemical responsible for making people feel tired. In doing so, it boosts alertness and increases the release of stress hormones such as adrenaline. While this helps many people stay awake and focused, it can overstimulate others.“There are multiple factors that play a role. One is genetics, especially variations in the CYP1A2 gene, which controls how quickly the liver metabolises caffeine. Slow metabolisers keep caffeine circulating in their system for much longer, so its effects are more pronounced and prolonged,” explained Dr Harshavardhan Rao B, head of department and consultant, gastroenterology, Ramaiah Memorial Hospital.He added pre-existing psychiatric disorders, acid reflux, peptic ulcer disease, certain heart conditions, pregnancy and medications that affect caffeine metabolism can all make people more vulnerable to caffeine-related symptoms.Doctors also warn consuming coffee on an empty stomach can alter several internal bodily functions. “The beverage triggers stomach acid production, which can cause heartburn or acid reflux without a food buffer to protect the stomach lining. Furthermore, caffeine relaxes the lower esophageal sphincter, increasing the risk of acid traveling upward. Without food to slow digestion, the bloodstream absorbs caffeine rapidly, which can trigger jitters, anxiety, a spiked heart rate, or immediate bowel motility,” Dr Kumar said.Filter coffee or Americano: Does it matter?From traditional filter coffee to double-shot espressos and iced Americanos, Bengaluru’s cafés now offer an endless variety of caffeinated drinks. While they may all contain coffee, they don’t affect the body in exactly the same way.“Because of its volume and milk content, regular filter coffee frequently produces prolonged acid reflux, whereas strong espressos create quick surges in the nervous system and cardiovascular system,” Dr Kumar said.Dr Rao pointed out that espresso-based drinks pack significantly more caffeine into a much smaller serving.However, the south Indian filter coffee, which is largely consumed in the city, generally contains more caffeine than an Americano. Its slow, gravity-driven brewing extracts caffeine over several hours, unlike the 20–30-second espresso shot used for an Americano. While chicory slightly dilutes the blend, the long brewing process results in a strong caffeine concentrate, experts said.Coffee isn’t the only source of caffeine, either. Tea, green tea, matcha and energy drinks can all contribute to a person’s daily caffeine intake. “If you’re sensitive to caffeine, you might develop symptoms even with these beverages, especially when intake becomes excessive or when multiple caffeinated drinks are consumed in a short period,” Shalini said.How to enjoy coffee without overdoing itStop consuming caffeine after 2pm to minimise sleep disruptionKeep daily caffeine intake below 400mg — roughly equivalent to two large lattesAvoid drinking coffee on an empty stomachStay well hydrated, especially if you’ve had more caffeine than usualKnow your own caffeine toleranceSeek medical attention if heart palpitations are accompanied by chest pain, fainting or severe dizziness
