Stretch marks while losing weight, and the aftermath
 

I'm in my late-teens, and have been heavy literally all my life. Sitting at about 30-35 pounds over my goal weight, i'm at least proud of the 15 I've so far lost.
My arms have shrunk, and begun to tone, and my face is notably thinner and far more defined. But, I'm struggling to drop weight off my stomach and thighs. Instead, i'm just seeing a battery of stretch marks on my inner thighs, beneath my stomach and on the tops of my breasts.
I'm naturally curvy and have large breasts, however I have never seen this happen before; The lines seem to come and go. Being totally gone one week, and back to their blue, angry selves the next. I'm currently using avocado oil as a 'remedy', and it does seem to help some.
I should also note that I have some tiny white 'spider web' stretch marks on my hips from a weight spike many years ago, which are 'flat' and 'smooth' but still visible on my ghost-white skin.

To anyone who this sounds familiar to: Is it normal to suddenly begin having stretch marks as you lose weight? Is it possibly hormonal and, importantly, at my age should I be concerned about this possibly being something that will need legitimate treatment in the future?

Also, is it normal for stretch marks to disappear and reappear repeatedly, despite weight loss being slow and not yo-yoing?

All of this sounds completely normal and can happen to not overweight and even underweight individuals as they go through puberty and their body changes quickly (eg get quickly get boobs, rounder thighs, hips etc).

Hormones definitely play a part - in puberty you can produce less collagen and elastin in the skin dermis, making it more difficult for the skin to with stand changes

it is common for stretch marks to appear and disappear. When they disappear they are not truly gone, just very pale. The color changes are due to blood flow changes.

My tips:
My favourite cream is shea butter/cocoa butter.
To help with their appearance make sure you do resistance work as you lose weight, whether it be weights, pilates or body weight exercises. I think long term this will help more than any cream. Also make sure you stay hydrated to help with collagen production. You may also want to look into taking a collagen supplement

In terms of worrying about the future, as your weightloss settles overtime, the stretchmarks are likely to go silver/white and pale. They can go very pale so they are barely visible. Saggy skin would have more potential of being along term issue, but even that firms up over time.

You are not really very far from your weight goal. As some so young and your body will probably respond really well to weightloss - you have already lost 15 pounds and have noticed positive changes in your body, that is exciting and means more should come as you continue on as you are.

Good luck

I second what the previous member said. Most teen girls develop stretch marks on thighs, buns, belly, and breasts. The good news is...they fade as you get older! Or, at least mine did.

While you're trying to lose weight, make sure you keep your skin moisturized! I also like cocoa butter. It moisturizes REALLY well.