I ain't a specialist or health expert, but here seems to be a very helpful site: Coffee, brewed from grounds, prepared with tap water, Nutritional Facts & Calories.
Gives you all the data you need for nutrition value in coffee. According to the site, coffee might be healthier than you think:
This food is very low in Saturated Fat, Cholesterol and Sodium. It is also a good source of Pantothenic Acid, and a very good source of Riboflavin.
Some of these must be very familiar eh? It is also better at weight losing that gaining :-). No need to throw coffee away because of a diet. Like hoc_age♦ said:
All of this nutrition data will certainly depend on the origin, roast, preparation methods, and other factors, which affect what gets into the cup from the beans. Unless you're eating the beans...