2. Induced osteoporosis. Drinking a lot of coffee for a long time is easy to cause bone loss. It is best to drink coffee after breakfast and lunch, so as to promote the peristalsis of the stomach and help digestion, and break down the high-calorie and high-fat foods you eat, which will not cause irritation to the stomach like drinking coffee on an empty stomach. It is best not to drink coffee after meals, for fear of affecting sleep. If you want to stay up late by drinking coffee, you may unconsciously drink too much, which is not good for your health. And liver diseases, digestive system diseases, pregnant women and children are not suitable for drinking.