Coffee is a beauty killer?

So far, there has not been any study showing that caffeine and melanin in coffee have an absolute relationship with increased melanin or skin aging. Conversely, moderate caffeine speeds up metabolism, improves digestion, improves constipation, and can improve skin roughness. About caffeine can accelerate metabolism, there is a saying that coffee will accelerate the burning of calories, to achieve the effect of weight loss, basically the theory is correct, but this burning of calories is not enough to reduce weight, if coffee also added sugar and creamer, from the calculation of calories is more not in line with the principle of weight loss.