Dr. Lee told Daily Mail Online that people watch the cringeworthy footage to relax because it gives them a sense of satisfaction and joy

, who is known as 'Dr. Pimple Popper', has more than 900,000 YouTube subscribers who watch her sometimes gruesome videos

The famed YouTube dermatologist known as 'Dr. Pimple Popper' has attracted millions of viewers with her gruesome footage of her patients' blackheads being extracted and their cysts being ruptured, but some breakout videos have proved to be more popular than others.

Dr. Sandra Lee, a dermatologist at the Skin Physicians & Surgeons practice in Upland, California, has a cult-like following of more than 900,000 YouTube subscribers, who take great pleasure in watching her squeeze and remove her patients' whiteheads, cysts, and everything in between.

After more than a year of Dr. Lee launching her captivating video series, FEMAIL has rounded up her top five clips, while she reveals what makes the cringeworthy footage so captivating.

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Cult following: Southern California-based dermatologist Dr. Sandra Lee is known as 'Dr. Pimple Popper' to her 900,000 YouTube subscribers who love to watch her extract patients zits and cysts

'Overall it seems like they are so popular because they actually make people feel happy and good!' Dr. Lee told Daily Mail Online. 'Like these pops squeeze out some endorphins in our own brains, and makes our hearts beat a little faster and puts us in a better mood.'

The doctor noted that she knows many people watch her videos before they go to bed to decrease anxiety and help them relax.

'I also think they give people a sense of satisfaction, of completeness. When a blackhead is extracted or a cyst is popped, the area is now clean, and the world is back in order,' she said. 'I hear all the time, "This is gross but oddly satisfying” and “I can’t stop watching these videos."'

Favorite: One of Dr. Lee's most popular videos sees her extracting a Dilated pore of Winer, which is a massive blackhead. The YouTube clip has received more than 12.3 million views since it was posted in July 2015

Can't turn away: Dr. Lee can be seen using tweezers to remove the large blackhead form an 85-year-old woman's back

Aftermath: After the blackhead was removed the woman was left with a dilated pore that Dr. Lee said may fill up again one day

BLACKHEAD REMOVED FROM AN 85-YEAR-OLD'S BACK: 12.3 MILLION VIEWS

Dr. Lee's most popular video to date sees her extracting a Dilated pore of Winer, which is essentially a massive blackhead, from the back of an 85-year-old woman who came into her office with her daughter in July 2015 to have growths on her leg biopsied.

It was the woman's daughter who brought Dr. Lee's attention to the blackhead on her mom's back, and in the clip Dr. Lee can be seen numbing the area before extracting the giant growth.

'It's like a little plug in a faucet,' Dr. Lee says as she uses tweezers to remove it.

And unlike the fans who helped the clip generate 12.3 million views, the octogenarian declined to see the pea-sized blackhead after it was taken from her back.

In the video's caption, Dr. Lee explained that the dilated pore that was left empty after the removal will shrink a but, but it won't go away entirely.

'If it tends to fill again, we can excise the enlarged pore, and place a couple stitches, so that she replaces the "hole" with a fine line scar,' she added.

Difficult to see: Dr. Lee said this woman's blackhead looks like a 'little disk' underneath the skin on top of her lip. The video of its removal, which was posted in January 2016, has received 8.7 million views

Under there: Dr. Lee showed viewers where the blackhead was located under the woman's lip

Down under: The dermatologist used a scalpel to slice into her skin (L) before squeezing out the blackhead, which was the size of a pebble (R)

PEBBLE-LIKE BLACKHEAD REMOVED FROM WOMAN'S UPPER LIP: 8.7 MILLION VIEWS

One of Dr. Lee's most watched videos features a woman who has a blackhead above her lip that looks like a 'little disk' under her skin. The blackhead is so deep down that Dr. Lee has to use a scalpel to slice open the area.

After widening the incision, Dr. Lee gives the skin a little squeeze and a hard blackhead the size of a pebble pops out, earning the clip more than 8.7 million views since it was posted in January.

Blackhead removal tend to be the most popular videos on Dr. Lee's channels, but she explained that her videos tend to fall into two categories 'soft pop' and hard 'pop'.

'Most people who watch pimple popping like or at least appreciate the soft pops,' she said. 'These are simple extractions of blackheads, whiteheads, [and] milia [and] may not require any local anesthesia, [have] very little to no blood, [and] minor trauma to an area.

'A hard pop is usually an excision or an incision and drainage. A surgery to remove a cyst, lipoma, or other growth that may pop from the skin, or an incision and drainage, which can be an inflamed cyst or abscess, which will have a lot of “goo”. [There is a] higher gross factor with hard pops. You essentially “graduate” to the hard pops. They are more “hardcore”.'

Trademark? Dr. Lee's videos featuring blackheads and whiteheads being removed tend to be the most popular

'Soft pops': This clip of her removing blackheads and whitehead from the face of a 90-year-old man in August has been viewed 7.9 million times

BLACKHEADS EXTRACTED FROM 90-YEAR-OLD MAN'S FACE: 7.9 MILLION VIEWS

Another one of her most popular videos, which has amassed 7.9 million views since it was posted in August 2015, sees her extracting both blackheads and whiteheads from the nose and face of a 'sweet man' who has been bringing his wife of 70 years to see her regarding the treatment of skin cancer on her face.

'He is not directly a patient of mine, but I couldn't help but notice that he has so many comedones on his nose,' she wrote in the caption. 'He tends to not pay much attention to himself, spending much of his energy and efforts making sure his wonderful wife is doing alright.

'She has more disabilities than he does, in fact he looks amazing for 90 years old!'

Dr. Lee told Daily Mail Online that most of the time she knows what videos will be very popular, but sometimes she is surprised, explaining: 'Essentially the favorites are the ones that have amazingly unexpected pops, and also may have a really interesting human story behind them.'

In the clip, Dr. Lee uses her trusty comedone extractor to carefully remove the blackheads and whiteheads from his forehead and nose.

'I just think that blackheads, or soft pops is where people start,' Dr. Lee noted. 'Many get a little braver and start realizing that they like the harder pops too. Blackheads are the basics of pimple popping.'

Before she became an internet sensation, Dr. Lee's YouTube channel only had a few thousand followers and was primarily used to share a selection of TV segments that she had appeared on.

However, it wasn't until she joined Instagram and started sharing short clips of herself treating patients in her dermatology office that she realized there is a prominent subculture of zit popping enthusiasts.

One of Dr. Lee's first full-lengh clips shared on YouTube in December 2014 shows her extracting blackheads from the nose of a widower named 'Pops' who had recently lost his wife to a chronic illness. The clip, which Dr. Lee calls one of her 'wonderful classics', has been viewed more than 1.5 million times, and over the course of a year, Dr, Lee's channel has amassed hundreds of thousands of followers.

'Hard pops': Dr. Lee thought this cyst was a blackhead before she extracted it. The clip of her removing the cyst from a woman's lower back in October has been viewed more than 3.8 million times

The result: The California resident has never shied away from sharing the most gruesome aspects of her job

EPIDERMOID CYST REMOVED FROM WOMAN'S LOWER BACK: 3.8 MILLION VIEWS

Although they aren't quite as popular as her videos of blackheads, Dr. Lee's clips featuring cysts still attract millions of viewers.

A video of her extracting an epidermoid cyst that she first believed was an oversized blackhead on a woman's back has earned more than 3.8 million views since it was posted in October 2015.

'It was flattened and disc-shaped because it's in a very tight area of the back, and it couldn't grow down or up easily, so it spread out very flatly, which makes it look more like a large blackhead,' she explained in the video's caption.

In the clip, Dr. Lee slices through the lump before squeezing it until it pops, pointing out that the cyst has a little sac that needs to be removed or it can grow back.

The woman admitted that she had the lump for three years, and it eventually got bigger and bigger.

After using forceps to get the entire sac out, Dr. Lee gave her patient a couple of sutures on her back to close the small wound.

Painful to watch? This clip of Dr. Lee draining an inflamed cyst on a woman's chest in February 2016 has already earned 2.6 million views

INCISION AND DRAINAGE OF INFLAMED CYST: 2.6 MILLION VIEWS

Another clip of her draining an inflamed cyst last month boasts an impressive 2.6 million views, despite the gruesome puss that was removed.

Dr. Lee explained in the caption that her patient had the cyst on her chest for awhile, but it recently became irritated.

'She has an inflamed cyst. Many people may call it an abscess, or an "infected" cyst,' she said. 'I put “infected” in quotes, because technically this is not an infection. When an epidermoid cyst ruptures, it creates a vigorous foreign body inflammatory response. This skin becomes warm, tender, painful, and swells, simulating an abscess.'

The doctor went on to say that 'when the cheesy material is evacuated' it 'often leads to rapid resolution of symptoms'.

Dr. Lee's patient admitted she was grossed out by the contents of the cyst, which had broken down and liquefied.

'Every time, I come here I get filmed,' her patient noted, and Dr. Lee said she was going to ask her fans to guess who she is.

After the incision and drainage, Dr. Lee prescribed her antibiotics because the area was so red and inflamed.

Family business: Dr Lee can be seen with her husband Dr Jeffrey Rebish, who is also a dermatologist

TV star: Dr. Lee snapped this selfie in October 2015 while shooting a segment on the talk show The Doctors

Fan memorabilia: Dr. Lee, who is pictured with her son and a friend, also sells hats and baby onesies featuring her YouTube name

Dr. Lee said she has been a dermatologist for a decade but before she started sharing her videos on YouTube, she never had the urge to pop her patients blackheads or cysts, explaining that like other physicians in her field, she tended to avoid them because they are benign growths that aren't covered by insurance.

'I will confess that I am a “born again popaholic”,' she said, noting that she now understands the 'hypnotic obsessive pull' pimple popping has.

While she said she enjoys removing 'great blackheads' and cysts the most, she likes abscesses the least because 'they are under pressure'.

'They can “squirt” you, and they are just an ooey gooey mess that can sometimes smell,' she revealed.

Dr. Lee revealed that her footage has gotten so popular that in one single day she had a total of three patients from Michigan, New Orleans, and San Francisco travel to see her because they have been watching her videos.

'On a daily basis now I’ll get someone who traveled from far so I can look at their skin,' she said. 'And if they have a pop that is “video worthy”, they are so excited.