DASH diet does not write specific guidelines for coffee. However, some people worry that caffeine-containing drinks such as coffee can increase their blood pressure. It is well known that caffeine can cause a short-term increase in blood pressure. However, a recent review claims that this popular drink does not increase the long-term risk of hypertension or heart disease, even if it has led to a short-term (1-3 hours) increase in blood pressure. For most healthy people with normal blood pressure, 3 to 4 cups of regular coffee per day is considered safe. Keep in mind that a slight increase in blood pressure (5-10 mmHg) due to caffeine means that people who already have high blood pressure need to be more careful with their coffee consumption.