"I haven't washed my hair with shampoo in 6 years."

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Can you imagine how greasy your hair would be after not washing it for a few days? One week? A month? Now imagine that feeling for SIX YEARS.

That’s exactly what Sarah Theeboom has done. The New York writer decided to try the “no poo” method (as in no shampoo) six long years ago.

The “underground” movement encourages people to say ditch shampoo and has enjoyed a recent surge in popularity. But six years ago, before it was a ‘thing’, Theeboom convinced herself to give it a go after discovering that giving up shampoo had turned her friend’s hair from dry and bushy to shiny and smooth.

“My hair is very fine and it tends to get greasy fast. I was in this annoying cycle where I shampooed every other day, and immediately after shampooing, my hair would be frizzy and static-y, and then it went straight to being limp and greasy. I didn’t really know what to do,” she told Seventeen. (Post continues after gallery.)

“My friend warmed that when you first stop washing, your hair and scalp get really icky for a while. But still, at least it felt like something to try,” she said.

A three week holiday to Thailand (where she would be spending most of the days at the beach) proved to be the perfect time to put it to the test.

RELATED: The 4 biggest mistakes women make when washing their hair

“I was not prepared for how intense those first couple of weeks really are,” she confessed.

“My hair was the greasiest it’s ever been. I had dealt with dandruff before, but there was a lot more during my three-week trial.”

“It was really unpleasant and I was so embarrassed that I didn’t want to show my head to anyone. I nearly cracked a couple of times and gave up on it. I felt like my scalp was going crazy!” she admitted. (Post continues after gallery.)

After returning from holiday and still stuck in the icky period, Theeboom resorted to wrapping headbands around her head and scrubbing her hair with water every time she showered.

Six weeks “of disgusting-ness” later, things finally started looking up.

“The dandruff and grease started going away. It didn’t look amazing, but I looked like a normal person again,” she said.

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“That happens to most people closer to three weeks but I think I prolonged the really awful period by swimming in the ocean and getting salt water in it.”

However it was another six weeks of her hair looking “so-so” before Theeboom saw any magical outcomes.

“I wasn’t doing anything differently, but my scalp just stopped overproducing grease,” she said.

"It adjusted to the new situation and normalized. I started to see what my natural hair was like when I wasn't constantly doing stuff to manipulate it. It was silky and wavier and totally frizz-free."

Six years later, she hasn't looked back.

While it's much more well-known now, Theeboom admits that she was met with some confused reactions when she told people she didn't shampoo her hair.

RELATED: The one type of shampoo that is ruining your hair

"One time I went to a hairdresser who freaked out and physically tried to shampoo me," she said.

She does, however, get A LOT of questions.

Common questions

Yes, she conditions. "I use conditioner whenever I feel like my hair needs it, which is about once or twice a week. I just use a regular conditioner, not a cleansing one, and I concentrate on the bottom half of my hair so I don't get split ends," she says.

No, she doesn't use a shampoo substitute. "Some people use bicarbonate of soda and apple cider vinegar as shampoo and conditioner replacements - I just wash my hair with water and always scrub my scalp really well with my fingers. When I have to clean my hair with something other than water say after getting highlights or swimming in a chlorine pool, I'll use a gentle, high quality shampoo that won't "reset" my hair," she says. We recommend: MooGoo Milk Shampoo.

RELATED: The Chop: “A hairdresser fried my hair, so I had to cut it all off”

Yes, her hair is clean. "I still wash my hair regularly (every two to three days) which gets rid of any dirt or sweat, but doesn't strip away all the natural oils my scalp produces to protect my hair," she says.

If you're planning to try no poo, choose your timing carefully. "The adjustment period is different for everyone, but for me the first few weeks were really not awesome. I definitely would not have felt comfortable going to school or work over that time. Definitely don't do it before a big event — like a wedding!"

Theeboom is quick to point out that she's not making a statement - it's just a choice she's made.

"I don't think shampoo is evil or bad for your hair. I still have good hair days and bad hair days, but overall, my hair looks and feels so much healthier," she says.

"Plus, I save a ton of money on shampoo and other products!"

Related: 7 physical signs of stress you’re probably not aware of.

Have you ever tried giving up shampoo? Would you?