Is it harmful to consume the majority of your calories through liquids only (i.e. milk, juices, waters, etc..)? Lets assume you are consuming close to a reccomended days worth of calories through beverages, and making sure you add any necessary vitamin supplements (to ensure you're getting all of the necessary vitamins and minerals needed on a daily basis).

I've heard that this is bad to do, and people usually gain weight back after losing weight with this method..

but it doesn't make sense to me, I mean, if you're consuming the right amount of calories (through liquids) and getting all of your vitamins and minerals, what's the difference whether it is liquid or solid?