Along with being accused of using steroids (which just so happened to be true), people have speculated LK's washboard abs were actually a result of implants.

In hopes of putting an end to all the speculation, Liver King -- real name Brian Johnson -- hit up Dr. Daniel Barrett, a Beverly Hills plastic surgeon, to administer a series of tests.

"I have an obligation to my tribe (you)... to take massive goddam action and do whatever it takes to earn back your trust," Johnson wrote on Instagram about the visit to the doc.

In LK's video, you see Dr. Barrett prodding at LK's abs with his fingers and a machine ... and eventually, he concludes that based on his expertise and what he sees and feels, there's no indication Liver King has ab implants.

Remember, Johnson, who was already a millionaire long before the viral Liver King persona was created, had to come clean about his steroid use after YouTuber More Plates More Dates exposed the "ancestral lifestyle" influencer.

Liver King's entire sales pitch was built on his "9 ancestral tenets" that he credited for his incredible physique -- but after he got exposed, many questioned if it was all a huge lie.

For what it's worth ... once he got caught, Brian admitted that he used steroids ... saying that he "f***ed up" and that he "misled a lot of people."

Recently, Johnson said on "TMZ Live" he fully expects his company's sales to be affected by his lies ... but what's most important to him, as he tries to regain the trust of his supporters, is that they're eating and living the right way.

All that being said, the tests don't confirm whether or not LK has had any ab etching done ... which is a procedure that sucks unwanted fat from the tummy to showcase the muscles more clearly.