All juices have a lot of sugar and artificial flavours. Even though some are healthy most aren't. All types of foods are different and there even more of these, but this is the only thing I can think of and before you hate on this at least I'm being honest.
The most healthy foods on this planet are prepared by mother nature. Fresh fruits, vegetables and nuts are what should be consumed for those who want to be the healthiest eaters on the planet. Processed foods that claim to be healthier on their labels are the ones consumers need to worry about. Healthy eating is all about making the right choices--there are tons of books on the subject that don't need a doctor's visit in order to be enlightening.
No I don't think that all healthy foods are all junk foods. See junk food is considered to be something that is really irresistible with lots of unhealthy Nutritions, but lots health foods are not junk food. Something like a protein bar with good taste is not a junk food.