Woman eats only Starbucks items for a year

One Seattle-area woman just gave the phrase "Starbucks junkie" a whole new meaning.

For an entire year, Beautiful Existence (yes, that's her name) ate all of her meals exclusively at the company's brands and documented it.

"I started designing these yearlong challenges, and I knew I wanted to do an eating challenge because eating is a really large challenge that many people are interested in and want to take on," said Existence in a phone interview.

For a year, Beautiful Existence ate only items made by Starbucks or Starbucks-owned brands.

Beginning Jan. 1, 2013, Existence dined only on items from Starbucks, Roy Street Coffee & Tea, Teavana, Tazo Tea, the Starbucks corporate cafeteria and Evolution Fresh. Her interest in the company was piqued by her sister's nearly eight-year tenure as a Starbucks barista.

"They've treated her really well. They were on my radar as a company I'd want to explore and find out more about," said the 40-year-old part-time undergraduate student at Bellevue University and former small-business owner.

The challenge was the latest in Existence's yearly pacts centered on brands. In prior years, she's shopped exclusively at Goodwill and tested out advice from Parents Magazine. This year, she's planning to learn more about outdoor equipment retailer REI by trying more than 80 recreational sports.

Existence estimates she spent more than $7,000 on Starbucks products last year. To put this in perspective, the average female 19 to 50 years old spends about $252.50 a month on food eaten at home as part of a moderate-cost budget, or about $3,030 per year, according to the Department of Agriculture.

Although Existence tried to stick to a budget, her purchases added up to more than she anticipated spending.

"I thought it would be over $5,000—but $6,000 at the most. It was definitely a bit more than I thought," she said.

Although Existence's challenge is somewhat reminiscent of Jared Fogle's vow to eat Subway regularly to lose weight, she said she has not received any special consideration from Starbucks.

"They've been incredibly kind and generous, but they never paid me or gave me discounts," she said.

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But the company did stay in regular contact with her about new items throughout the year, said Linda Mills, a spokeswoman at Starbucks, in a phone interview.

"We applaud her efforts and encouraged along the way, but no money was ever exchanged," Mills said. She added that Existence "often sets lofty and unattainable goals for herself, and she really meets them head on."

While Existence's challenge is no small feat, in many ways, her timing couldn't be better. During the year, Starbucks added dozens of new items after its acquisition of La Boulange, a San Francisco bakery chain. Her location also meant she was nearby to a plethora of different options in Seattle, where Starbucks is based.

After eating only Starbucks' foods for a year, Existence said her taste buds hadn't quite adjusted yet to the newfound variety when she sat down for her first post-challenge meal—fried fish.

"It was a really new flavor to my palate after an entire year, and my taste buds were in shock," she said.

After a year of chowing down at Starbucks, Existence said she is not quite sure when she'll return to the coffeehouse chain.

"I don't know when I'm going to go back to a Starbucks, but I'll always have Evolution Fresh juice from now on," she said.

—By CNBC's Katie Little. Follow her on Twitter @KatieLittle.