Buttermilk is a beloved summer beverage in India, but it may not be suitable for everyone. Those who are lactose intolerant can experience bloating, gas, and diarrhea, despite the fermentation process reducing lactose levels. Individuals with chronic respiratory issues, such as asthma or sinus congestion, might find that buttermilk aggravates their conditions due to its mucus-promoting properties in Ayurveda. Kidney patients should avoid it because of its high potassium and phosphorus content, which can strain renal function. Additionally, while many drink buttermilk to soothe acidity, its lactic acid can irritate the stomach lining for those with peptic ulcers or severe acid reflux. Lastly, people prone to joint pain may notice increased stiffness after consuming buttermilk, especially in colder weather. Therefore, it is advisable for these groups to limit their intake of this popular drink.