Will I see any noticeable results from an internal bra?

I understand you are struggling with your weight. As a 48DD, undergoing surgery with your BMI is risky. Please seek the help of a dietitian, weight loss clinic, or your primary care physician before moving forward with your breast lift. An internal bra has been described to mean many things. However, in The Horndeski Method/Bellesoma Method it is a proprietary technique that uses your own tissues to anchor, shape, and lift your breasts higher on your chest to achiever upper pole fullness and actually raise the entire breast footprint (unlike most lifting techniques). THM does not use any type of foreign material that might cause complications. This technique was developed to achieve maximum lift without a vertical scar and without implants. I have attached an example of what this technique can achieve. Best wishes,

An internal bra is a technique to help stabilize and raise, if necessary, an implant internally.  That does not address the breast itself.  If your breasts are saggy already, then a formal external lift ( mastopexy) is what would be needed.  The external lift allows you to raise and reshape the breast tissue and skin as needed.  I recommend going for a few consultations with board certified plastic surgeons and see what will work best for you.  I hope this helps.