I only eat fish and I eat lots of fruit and vegetables, but I also like my junk food and usually once a day I eat either potato chips or cake, so yeah, I have a balanced diet.
I think, again, if you wanna eat healthy, eat berries, eat healthy grains, eat a balanced diet, and that will give you enough nutrition, antioxidants, vitamins as any superfood would give you.
You can prevent or delay type 2 diabetes by making simple lifestyle changes, such as getting 150 minutes of physical activity a week and eating a balanced diet, including fruits and vegetables.