My girlfriend used to be fat and her boobs & nipples shrink after a lose weight surgery, is it normal? (photos)

Breasts change all the time, especially with weight loss or weight gain.  The areolas may change as well in diameter/color.  As women age, or have children, their bodies change as well.  Any weight loss or gain for female or male can affect his or her body.  If there are any major concerns, it is best to do a follow up appointment with the surgeon.  I also agree with the Dr. Gary ross, about any comments or concerns regarding your girlfriends breasts.

Weight loss and gain can affect the appearance of the breasts as can other changes, such as pregnancy. If your girlfriend has concerns I encourage her to meet with her doctor to discuss them. I sincerely hope she has granted you permission to post these photos.

It is perfectly normal for a woman's breasts to reduce in size with moderate weight loss.  The breasts can also drop lower with weight loss or after child birth.  She can consider a breast lift (which will address the size of the areolas, but not the color) or a combination of a breast augmentation (implant) and lift.

Yes these changes to your breasts are normal after significant weight loss. A breast lift with augmentation would help for the breast ptosis(droopiness) and breast shape (more superior cleavage). The color of the areola will most likely not change. Hope this helps!

It is common for the breasts to get smaller after weight loss and the areola will shrink a bit.  This is normal.  If there are other concerns speak to your surgeon.

I'm not sure whether your girlfriend is aware that you are posting her pictures and has given consent for this. I am also not sure whether the terminology of "fat" is something she would use to describe herself. I think it would be best if she were to ask for advice is she is troubled by this.Weight loss often reduces volume in the breast and with age breast size and shape change. Furthermore areola colour can change. 

The changes that you describe in your girlfriend are not unusual following weight loss.  Areola expansion with breast augmentation can also occur.  Please consult a board certified plastic surgeon.