It should be noted that only 30% of Canadians and 10% of Americans succeed in following this recommendation.
Raising it to 10 servings could therefore discourage some of them, all the more so if it turns out that the gains are not huge.
Juice often contains sugar
Some fruits and vegetables are better than others. Canned fruits should be avoided in particular since they have been associated with a higher risk of mortality, possibly due to sugar that they contain.
Fresh fruits and vegetables should therefore be preferred, whether raw or cooked. The juice should be excluded from these daily portions, due to the added sugar it contains.
And there is one last important nuance to all of these studies. Overall, those who eat the most fruits and vegetables are often the ones with the best lifestyles. They are more active, they do not smoke, and the contents of their plate are generally healthier.