Drinking a small amount of coffee with cola is not harmful, but if you drink a large amount of coffee with cola over a long period of time, it may lead to excessive calorie intake, increased risk of dental caries, and calcium loss. 1. Excessive calorie intake: black coffee itself is low in calories, but cola is high in calories. Each 100 milliliters of cola contains 41 calories, of which 10.58 grams of carbohydrates, protein and fat content is very small. So Coke contains a lot of sugar, long-term consumption of Coke, easy to lead to excessive sugar intake, which is converted into fat, making the body fat. 2. Increased prevalence of dental caries: The sugar in cola can produce acid in the mouth, decalcifying the teeth and thus triggering dental caries. Drinking large quantities of coffee and cola over a long period of time will lead to an increase in the prevalence of dental caries. 3. Increased calcium loss: Caffeine in coffee and cola has a certain diuretic effect, and after drinking a lot of coffee, it leads to an increase in the amount of urine and the loss of calcium from the urine. Phosphate in cola will compete to inhibit the absorption of calcium, while increasing the discharge of calcium from the kidneys, which will also lead to calcium loss in the long run. Coffee with Coke is not a healthy drink. In real life, it is recommended to use sugar-free beverages such as green tea, lemon tea, and floral tea, or plain water or mineral water instead of sugary drinks to ensure good health.