It is one of those things that most of us drink, yet we often believe it is bad for you.
I’m not going to say it is all good, but neither is tea (even green) nor most of other beverages we take in.
I believe that it is more a question of what you do with… and then how it influences your body.
*image found via Google Search originating from
Some recent studies show that coffee can actually be good for you…. provided you approach it with some knowledgeable.
Rule number one…. no instants!!! Although it is proclaimed that they do not have additives, per definition they contain much of dregs (more on that later). 
How does coffee work? Well, it makes your organism use up your stored sugar reserves, thus boosting your energy.  Thus it is essential then that you drink it AFTER a meal. 
Cup drunk after a meal will not increase your chances of getting stomach ulcers (which are often mentioned as one of the problems), because it will make organism take advantage of the sugar that you have already brought in with a meal instead of the one stored.
Such a cup provide you with a boost for up to 4 hours. Apart from using up the carbohydrates… it also increases blood pressure (that’s why it can be bad for those with heart issues).
Other things that coffee does, which are bad, but can be solved. Well it washes our magnesium from your blood increasing stress level and negatively impacting muscles (including heart)… how to balance that? add to coffee a spoon of cocoa. Or simply drink cocoa later.
It also leaves dirty brown stains on your teeth….nothing simpler… drink it with milk and no stains will be left. 
Then, there are many kinds of coffee and things like place of growth, roasting, transport and handling do matter. If you buy ‘cheap’ coffee don’t expect it to be good for you. Cheap does not have to mean only the price here.
How to recognize good coffee? Well it is not that hard. Simply brew it (best way to test is brew the Turkish style in a pot). Let is sit for a 2-3 mins, as to let the dregs to settle. If the resulting infusion/brew is 
full of ‘dust’ and at all not transparent… forget about that brand. What does most damage are the dregs. 
Thus the 2nd rule of thumb is … the clearer/the most transparent brew is the best. 
It is true that dark roast coffee has most flavor… but it is also harder on your heart and kidneys and does not provide you with the same ‘kick’ as the gold type. Gold coffee is less ‘burned’ and milder in taste. 
It is also better for your body. Generally, it has greater impact in terms of energy boost then the dark roast. There are scientific proofs for that, but I really would hate to dump that stuff here (just too boring).
Best is if you by the beans and ground it at home. 
Also brewing impacts the way our body reacts to it. Best by far the best two ways are the pressure coffee express and those old-time ‘overflow’ type. Turkish brew can be even better, but it does need some filtration in order to avoid the ‘dust’ that tends to accumulate in our body later. Also simple Italian style pots are great, but only if you do use good quality coffee. 
The good things…. coffee is high on antioxidants thus prevents to some extend aging. Recent studies shows that people drinking 3-4 cups a day have 70% lower risk of getting Alzheimer. It also lowers
risk of prostate cancer,  dementia, some types of diabetes and also numerous heart problems. And best of all (at least for some)… it has 0 calories if drunk clean 😉
So drink Coffee… it is not bad at all…but do it with brains.