Again, where the fuck are the mainstream media people saying Marilyn Monroe was fat? The only people who say this are, as Jessica Siegel says, reacting to the "recent cultural bias toward skinnier girls" which has always been a bunch of b.s. Skinny girls have always been in vogue, and women have always been jealous of skinnier girls, and skinny girls have always made derogatory comments about fat girls. (Check out Mena Suvari playing Marilyn Monroe and talking about Liz Taylor's fat arms.)
The only thing that's changed in the past 10, 20, 30 years is people started getting fatter and fat people started to get really defensive about it.
In the 1990s you have two things going on: 1, the anti-glam/anti-big-hair grunge/post-grunge and a "girl-next-door" type in every movie and every magazine cover -- Winona Ryder, Meg Ryan, Julia Roberts, the "Friends" cast.
2, Playmates became mainstream. Hefner's always had an obvious personal preference so bleached blondes with big tits started showing up everywhere -- Pamela Anderson, Jenny McCarthy, Anna Nicole Smith.
Are these women any skinnier than Paulina Porizkova or Christie Brinkley or Cindy Crawford or Heather Locklear? I cannot discern any difference at all.