The YouTube sensation, who has racked up more than 919,000 subscribers to her channel, is a rheumatologist specialist from Canada.
“A normal healthy tongue is pink with little bumps,” Dr Deshauer told her viewers.
“But if your tongue looks red and smooth (we call this glossitis), it can be from a nutritional deficiency.”
Dr Deshauer added: “If your tongue suddenly gets bigger, it’s probably an allergic reaction or an infection.
“But if this is happening slowly over time and your tongue is continuing to grow, [it might be] hypothyroidism.”
Hypothyroidism (an underactive thyroid) is when the “body isn’t making enough thyroid hormone”.
Alternatively, a growing tongue could be a sign of “acromegaly, which is when it’s making too much growth hormone”.
Dr Deshauer said: “It could also be amyloidosis, where amyloid proteins get deposited into your organs, including the tongue, which would make it grow.”
As for a white coating on the tongue, which is considered normal, it’s only problematic if it doesn’t go away after brushing.
Dr Deshauer elaborated: “If you brush your tongue, the white coating should go away.
“But if it doesn’t, it may mean you have thrush, or oral candidiasis – a yeast infection.”
Oral thrush could be caused by taking antibiotics that “changes the bacteria in your mouth and gives yeast an opportunity to grow”.
Yet, if you have white lesions that are “more flat and hard”, it could be leukoplakia.
The painless condition could heighten your risk of mouth cancer, the NHS warned, so do get it checked out by a dentist if it remains for two weeks or more.
Two risk factors for developing leukoplakia include smoking and drinking alcohol.
“It’s important to keep track of this because the patches can develop into cancer, so talk to your dentist or doctor if you notice something like this,” emphasised Dr Deshauer.