That's the headline of an article in a swedish newspaper from a few days ago.
For you swedish speaking people: http://www.aftonbladet.se/halsa/article13360948.ab
And a short explanation in english:
It says that 12 out of 13 girls between the ages of 11 and 18 eat too little fruit. And now the scientists are warning for the serious health problems this may cause in the future. For the boys, 7 out of 8 don't eat enough fruit every day. You get antioxidants and vitamins from fruit. Cancer can be caused by an inflammation that makes the cells increase. And the antioxidants affects the inflammation in that way so the risk for this won't be as big. Same thing for heart diseases.
Personally, after reading the lchf book, I don't believe it's good too eat 5 portions of fruits per day because it's so much fruit sugar in that, but 5 portions of vegetables would be much better for your blood sugar.
It's soooo important that you get your vitamins every day. Maybe you think that you are young and don't have any health problems, so it's not as important what you eat right now. But it is, because it will prepare you for your future health.