It's at least healthier than milk chocolate. Cocoa itself has high antioxidant effect. And the antioxidant content in dark is triple that of milk chocolate. Cocoa has been shown to improve arterial function within hours of consumption. https://nutritionfacts.org/video/dark-chocolate-and-artery-function/
I have a very pragmatic "common sense" question to ask with respect to the health benefits of dark chocolate: A typical 70% bar is 35% fat (required to make it fluid enough to work with), and 30% sugar (the remaining % above and beyond the cocoa content). SO.... Can someone name one more "healthy food" other than dark chocolate which is composed of 65 PERCENT FAT AND SUGAR ? I've been involved in the food industry for 12 years now and I can't think of a single one... Healthy pfffffft!
Yes, it has, but I don't know if it should be considered a health food. Of course, it can have its positive attributes, but I feel when people think of something as healthy they can tend to overdo it, and even though there is less, there is still sugar, which as you said should be reduced for a healthy diet.
@AlexWild - The topic has come up a lot and I don't think there's a lot of debate about health benefits ... and scientists are discovering new reasons to like dark chocolate on a regular basis. One important thing that is consistent across the research is to reduce the sugar content of the chocolate you eat.