I am frequently told by patients that they are confused about what is healthy to eat and what is not. Very often the popular media and marketers try their best to fuel this confusion with clever advertising and misdirection but my answer is always the same. The further the food is from the farm to your fork the worse it may be for you. Any food product that is highly processed is probably not a healthy choice. An apple is always going to be a better choice than apple juice.
If you look objectively at the box or bag in the store and there are ingredients you can't pronounce, put it back! If you can't pronounce it, don't eat it!
Seek out fresh foods, preferably organic, and if need be shop the supermarket or farmer's market sales for that week. If you follow the sales, chances are you will eat a more varied diet on a regular basis and you might save some money too.