Tsuchiya's career began at the age of fourteen when she was hired to model for Seventeen. Her demand grew, and by 2002 she was doing television ads for UNIQLO, Edwin, and KOSE products.
She tried hard to lose weight during her stint as a model. At 1.67m (5 ft 6 in) and 44kg (97 lbs), she was considered to be overweight and short for a model in Japan. She experienced mental and physical agony at the time, and can hardly remember anything she ate back then. After an incident when Tsuchiya was fifteen years old in which she awoke starving one morning to find that her legs didn't work due to severe malnutrition, she was forced to drag herself — using only hands — to the refrigerator.
According to her, some models would tell her, laughing, "How can you keep modeling with no shame?", "What's up my little girl, how much did you eat yesterday?", or simply, "Oh my god! You're one ugly fat bastard!" and then laughed at her. Someone said to her in a backstage dressing room, "Get out of here, fat is contagious, asap, asap, you smelly twat!"(according to Anna, that one was the same age as Anna, 14, and "freaking pretty"), when she modeled for Seventeen.
Tsuchiya was quoted as saying, "We were all teens at that time. I guess you guys expect some epic stories like — Anna did it, and those who laughed at Anna now have miserable lives flipping burgers at McDonald's or distributing handbills at Jusco or appearing in porn videos — but sorry, y'all know God is such a daft prick, now some of those who laughed at me have got bigger successes than me and are super rich... ahh, super stars. I sometimes feel frustrated with it, but okay... I mean, they made me better".
Anna spent her middle-teenage years modeling for Seventeen, and in the course of time, she made friends with some of the same-aged female models, or older models including Yoshika Yuhnagi (1983 - 2001), and soon she began to put up at their apartments or condominiums, where they lived by themselves. Around this time, she began smoking and drinking.
Anna eventually semi-retired from modeling, becoming a singer and actress. She explained the reason for the retirement as a "giving up" – "I realized I can never compete with such gifted superhuman people like her any more" – "If I wanna be a girl like them, I need to die of hunger 100 times or more. ... I entered the music field, and since then, I've never met a person who calls me fatty. I became an actress and have worked with many people. One day, Kyo-chan said to me, 'Hey, you have a beautiful body!', 'You're always stunning!'. I hugged her at that very instant!"
Even though she got involved in other projects afterwards, to this day she remains an in-demand model for magazines like Kera, Soup, and Zipper.
Though Anna was born and raised in a mainland region of Tokyo, she often uses many slang phrases that are normally used only by the people living in the southern islands Kyushu or Okinawa, and she sometimes speaks in southern dialects that the mainland people can't understand. According to her, the majority of Seventeen models she encountered, especially the most successful, were from the southern islands or northern regions. Without much effort, she managed to learn various dialects and slang from them. These legacies subsequently helped Anna when she acted as her most noted role Ichigo, a punk-style Bōsōzoku delinquent girl, in a film, Kamikaze Girls, which increased her popularity.
According to a model who modeled for Seventeen at the same time as Tsuchiya, some of those who often teased Tsuchiya had recognized her as an admirable person, because Tsuchiya often tried going on an extreme diet as if she had "almost died". They knew much about it so they looked on her as "a tough one" and in the course of time began to identify her as their fellow, and called her by her name, namely Anna or Tsuchiya, while other "overweight models", like Keiko Kitagawa and Kaela Kimura, were always called by their extremely vulgar nicknames. Some of them praised Tsuchiya afterwords, like "well done".