Only have fruit whole, never juiced or dried

Fruit juice is not healthier than whole fruit in general. Even if the juice is freshly squeezed on the spot, drinking the juice is less healthy than eating the fruit whole.

First, the pulp and skin of the fruit that is left behind is high in dietary fiber. Dietary fiber plays a larger role than just promoting regular bowel movements. When you eat a fruit whole, the dietary fiber in the pulp binds to the natural sugar in the fruit as it travels through your gastrointestinal tract. This binding action makes it harder and take longer for your body to absorb the sugar. As a result, the fruit's sugar accumulates in your blood at a lower and slower rate if you eat the fruit whole than if you drink straight fruit juice. This process lets your body use the sugar more as a direct energy source. In contrast, drinking straight fruit juice leads to a spike in blood sugar. Sensing that you have more sugar than you need, your body quickly releases insulin, leading to a large amount of the sugar in your blood being converted to fat and glycogen. In this way, the blood sugar spike leads to a blood sugar dip (unless more food is eaten), leaving you hungry again. And being hungry makes you eat more. In this way, drinking pure fruit juice leads to poorer regulation of blood sugar and increased calorie consumption, when compared to eating whole fruits. People who are especially sensitive to blood sugar levels may even suffer headaches, weakness, and irritability after drinking fruit juice, whereas these symptoms do not arise when eating the fruits whole.

A study lead by L. F. Burroughs published in the American Journal of Clinical Nutrition states, "Healthy volunteers ingested sugar-equivalent meals of oranges and orange juice and of grapes and grape juice. Satiety, assessed by two subjective scoring systems, was greater after whole fruit than after juice and the return of appetite was delayed. With oranges, as previously reported with apples, there was a significantly smaller insulin response to fruit than to juice and less postabsorptive fall in plasma glucose." Interestingly, a study lead by H. H. Stratton and published in the journal Pediatrics found that, "Among children who were initially either at risk for overweight or overweight, increased fruit juice intake was associated with excess adiposity gain, whereas parental offerings of whole fruits were associated with reduced adiposity gain."

Secondly, the pulp and skin of many fruits tends to be high in vitamins and other nutrients. Extracting just the juice leaves behind much of these nutrients. For instance, oranges are a rich source of flavonoids, but much of the flavonoids are stored in the pulp and not the juice.

Processed fruit like juice, dried fruit or canned fruit also often contain added sugar, causing higher blood sugar spikes.