Lyric Waiwiri-Smith is a 22-year-old culture reporter for Stuff, where this story was originally published.

This summer, standing in a thrift store changing room with my eyes on the brink of tears and a pile of clothes on the floor, I came to a realisation: my body is no longer something I recognise.

My thighs have taken me up two clothing sizes and my chest and hips have grown in only a way I can assume has been orchestrated by my biological clock to prepare me for motherhood (my brain seems to have missed the memo that I had stopped being a child and was ready to raise one instead) – what happened to the smaller figure I had last summer?

I left that changing room empty-handed and defeated, filled with the level of confusion and self-loathing only a nightmarish shopping trip can achieve – was my body supposed to be changing so fast?

The confusion of it all led me to a trend social media users referred to as the “second puberty,” where women confide in each other the drastically changing state of their body from teenagehood to their adult years.

The phrase is particularly popular on TikTok, where women share their stories of dramatic weight fluctuations, sudden chest and hip growth, and frustrating breakouts of adult acne, among other unexpected bodily changes.

Although “second puberty” is not an official medical term but more-so an internet colloquialism, the phrase has garnered popularity for being a simple way to describe the changes your body experiences as you age through your 20s, 30s, and 40s.

TikTok’s takeover of the social media realm has become a catch-22, allowing not only a space for those dealing with negative body image to find support, but also becoming a breeding ground for fatphobic and anti-ageing rhetoric, often presented under the guise of being pro-wellness or sold through fear-mongering, capitalising on young women’s insecurity with the natural process of growing older.

Videos of women outlining their often obsessive attempts to control the natural processes of their bodies garner hundreds of thousands of views on TikTok and across other social media platforms, where the idea that the body can always be optimised and there is always a higher, healthier, slimmer self to become to festers like a disease.

Perhaps one of TikTok’s worst trends in terms of promoting negative body image is ‘body checking’, wherein slender women will show off their bodies for the hyper fixation of their audiences.

Many users go crazy for this kind of content, a succubus whose fuel is low self-esteem, with young girls posting self-loathing comments such as “body tutorial?”, as if naturally slim figures come with a one-size-fits-all routine that can transform anyone into supermodel Bella Hadid.

Gaining weight in your 20s is a common life change, with many of us transitioning from the energetic lifestyles in our youth to desk jobs and lifestyles that make prioritising (and often affording) eating healthy wholefoods difficult to manage.

I’m not trying to achieve a body positive relationship with myself – I am personally more inclined to the idea of body neutrality, where I don’t have to be led by feelings of hate or love for my body, but treating it more as something I can respect and appreciate for its abilities (this isn’t to say the body positivity movement, which has provided solace for many plus-size and disabled people, is the wrong relationship to have with your body).

As an able-bodied person in their early 20s, I have very little to complain about, but the grief of growing older and losing a part of myself I had spent so long waging a war with before realising it was perfectly fine the way it was has been mentally ravaging.

I know the expectation that my body should remain the same from my teenage years into my early adulthood is ridiculous, but it doesn’t take away the grief I feel.

Recently, a friend told me she was expecting a baby, a surprising piece of news which has reduced me to joyous tears on multiple occasions since finding out.

Her pregnancy, in all of its beauty, has reminded me of the magnificence of the human body – our ancestors had been regarding the body as beautiful and sacred long before celebrities and influencers were selling us the lie that we should fear it.

I wish I could trade back all the time I had spent denying myself appreciation and respect and instead fill it with this wonder. My body may not look the same as it did when I was a teenager, but I think I’m happy I’ve allowed it to change.‍

If you want to discuss body image issues, check out these resources

1737, Need to talk? Free call or text 1737 to talk to a trained counsellor.

Mental Health Foundation 09 623 4812, click here to access its free resource and information service.

thelowdown.co.nz Web chat, email chat or free text 5626

What's Up 0800 942 8787 (for 5 to 18-year-olds). Phone counselling available Monday-Friday, noon-11pm and weekends, 3pm-11pm. Online chat is available 3pm-10pm daily.

Youthline 0800 376 633, free text 234, email talk@youthline.co.nz, or find online chat and other support options here.