Sherbet is similar to sorbet, except sherbet usually has some dairy. Although the butterfat contained in sherbet is certainly Paleo-friendly, it’s not enough to outweigh the negative health effects of all that sugar.
Whole Foods vs. Juice
Sorbet and sherbet are usually sweetened with fruit juice in addition to sugar. Although many of us were taught from childhood that fruit is healthy (and fruit in whole form can be healthy), fruit juice contains all the sugar of the fruit without any of the fiber to help slow the digestion of that sugar. The result is a spike in blood sugar that inevitably leads to a crash, leaving you feeling tired cranky, and craving more sugar.
Mark Sisson has a comprehensive list of the different types of sugar and why they should be avoided.