Try eliminating foods one by one that you may think are causing bloating, to achieve that flat tummy.
Unfortunately there are lots of healthy foods that can make you bloated. Just because a food has a lot of antioxidants or is high in cancer fighting agents such as broccoli, doesn't mean that it will always react well with you. Everyone is different and understanding what works best for your body is really important so you can feel your best and have that flat tummy without looking bloated and feeling uncomfortable. Some foods known to cause bloating are: nuts, apples, avocados, broccoli, brussels sprouts and cauliflower just to name a few. Dairy is a food group that is very well known to cause bloating which is why I don't recommend it. In fact due to all the other not so great qualities, the only dairy I recommend is organic greek style yogurt with no added sugar and all the live cultures.
If you are eating 'healthy' and feeling bloated start by eliminating some foods from your diet to see what exactly is affecting you.