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Yet, the books never explicitly say anything about Sam's weight; Gollum calls Sam a variety of names, including cross, rude, nasty, suspicious, not nice, or silly. But never did he call Sam fat.
Stoutness is a very much a general trait among Hobbits. Tolkien mentioned often that the Hobbits enjoyed eating and drinking: in Letter 27, he describes them as being "fattish in the stomach, shortish in the leg", and like humans, they were inclined to expand as they got older - as shown in the books by Frodo himself, who was middle-aged for a Hobbit (he was around fifty when he set out to destroy the One Ring) and getting rather stout before losing much of his weight by walking and running a lot:
Ainda assim, bem ao contrário do que os filmes gostariam de ter, Acredite, Sam, sendo jovem e trabalhador, provavelmente era mais apto do que Frodo, Pippin ou Merry (que são todos Hobbits de classe alta).Looking in a mirror he was startled to see a much thinner reflection of himself than he remembered: it looked remarkably like the young nephew of Bilbo who used to go tramping with his uncle in the Shire; but the eyes looked at him thoughtfully.
A ilustração de Pauline Baynes sobre a Irmandade, feita enquanto Tolkien estava vivo, mostra todos os quatro hobbits como tendo as mesmas proporções . Curiosamente, o filme mostra Sam como mais ou menos a mesma construção quando ele deixa Hobbiton e quando ele atinge Mordor, mesmo que ele tenha algumas semanas de semi-inanição.