One of the problems with fruit juice is that it provides all the sugar with almost none of the fiber to help slow the absorption of sugar in the body. If fiber is added back to the fruit juice before drinking, for example with ground flaxseed, does this help prevent the body from absorbing too much sugar? (Keeping in mind that we are now learning that juicing is not actually so healthy.)
What about more generally eating fiber alongside sugary foods? For example, eating raspberries or figs or almonds alongside a slice of cake? Does this help slow the absorption of sugar from the cake to any noticeable degree? (Not making the cake healthy per se, but does it help make it somewhat "less bad"?)
If this does help, why doesn't the food industry add more fiber to processed foods?