Well, if you have more than one character around, it's definitely better to split the dumb labor up between as many as you can. If you have alts that you don't care about grinding the attributes up on, the hunger level has absolutely no meaning, and thus it merely becomes the most energy producing foods for the labor into making them.
If you're playing solo and care that much about efficiency, best to factor in FEP gains with that, too, because not much point in eating a bunch of rats and frogs that will produce little to no attributes mid game and later. Even early game once you get past 20-30 required FEPs, they start losing their appeal from the total lack of FEP gains (other than as a variety food).
Also going to note I took a look at the wiki article and made a couple corrections (old information from w8-9) and added a section about the Symbel bonus from eating from a proper table setting.
http://ringofbrodgar.com/wiki/HungerAlso note that I flubbed and wiki says it's approximately 4 days to drain 100% at the 2x bonus level
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