From my understanding, the amount of fructose in fruits is low, and the some fruits that are considered "high" have only approx 50% of the carbs coming from fructose. This could be wrong, please correct it if it is, I don't have a sugar composition chart and don't know where to find a good one?
If that is true, then someone would have to eat 100g of carbs from high fructose fruits to get 50 grams of fructose, but chances are they will be eating a variety of fruits, including those with a low fructose content, so then they would have to eat at around 150 grams of carbs from fruits to get 50 grams of fructose. I don't know what the exact amount of fructose per day is allowable before it becomes sat. fat but many people say around 50, so I"m just using 50 as an example. If its more like around 60 or 65, then you could eat alot more.
This is why I don't think fruit juice is good, because then you could easily be eating too much fructose, but when you eat real fruits, its much harder.