Chocolate can be both healthy and unhealthy at the same time. There are many variables that play a part in this. First, if a person eats large quantities of chocolate with the processed sugar in it, then this is an unhealthy choice. However, there are healthier chocolates because they contain less sugar and they have more cacao. It is better to have more cacao powder in a product.
If a product has more than 65% cacao in the ingredients, then this is considered to be a healthy chocolate product. Dark chocolate usually has more cacao than milk chocolate. Also, portion size is important. If a person eats just a little chocolate and not many candy bars, then this might be considered healthy.