People usually drink buttermilk or chaach on hot summer days but tend to avoid it when there is a nip in the air. So is it safe to include a glass of buttermilk to your diet during winter? The sour, creamy beverage consumed in many parts of the world is prepared by blending together a few spoons of natural yoghurt/curd and water. It contains no butter and is low in fat and calories, making it a healthy drink. In fact, what it contains are many vitamins and minerals. Often, spices such as cumin powder, pepper, ginger, green chillies, curry leaves and coriander leaves are crushed and added to the mixture to enhance its taste and therapeutic benefits.