Jack Osbourne has declared he is "perfectly healthy" and slammed speculation over his weight loss as "f****** insane."

The Osbournes star, has slimmed down over the last few years and dropped extra pounds during his appearance on UK TV show I'm a Celebrity... Get Me Out of Here! last year and he's now spoken out to shut off critics who express concern over his weight loss.

In a video posted on TikTok, Jack said, "I cannot believe I’m having to actually make this f****** video. If I see one more article written about me saying how I’m sick, I’m grossly underweight.”

"What’s going on? It’s f****** insane. I have lost no weight since I got out of the jungle doing I’m A Celebrity, what? Six months ago?” he exclaimed.

"I’ve been the same f****** weight. The only difference is I shaved my beard and opted for a creepy moustache. That’s the only f****** difference,” Jack explained further.

He went on to speak about his weight loss journey insisting he has been dropping pounds slowly over a number of years.

The TV personality continued, "Now if we want to back up and we want to get real f****** personal, I’ve been consistently but slowly losing weight for the last three and a half years.”

"I shot up to about 220 pounds three and a half years ago and decided that I wanted to make some changes. So I did. What’s the big f****** deal?” Jack expressed.

"I’m five foot eight and a half and a 155 pounds (around 11 stone). It is perfectly healthy."

It comes after Jack's sister Kelly Osbourne called out her body-shamers who made fun of her appearance at the BRIT Awards earlier this year when she took to the stage with her mother Sharon to honour her late dad Ozzy Osbourne.

In a post on Instagram, she wrote, "There is a special kind of cruelty in harming someone who is clearly going through something. Kicking me while I'm down, doubting my pain, spreading my struggles as gossip, and turning your back when I need support and love the most.”

"None of it proves strength; it only reveals a profound absence of compassion and character. I'm currently going through the hardest time in my life I should not even have to defend myself. "But I won't sit here and allow myself to be dehumanized in such a way,” Kelly Osbourne wrote at that time as she detailed how much she was struggling to cope with her father, Ozzy’s death.