Wearing a bra that doesn’t fit
This habit is more common that one would think. Most bras are made of flexible materials, and over time with normal wear, they will eventually stretch out. But the bra’s primary purpose is to give support. Wearing an ill-fitting bra can contribute to breast sagging as the more your breast bounce around, the more stressed breast skin and collagen become.
You need to figure out what your bra size is, so that the cups adequately hold your breasts. About 80% of women are wearing a bra that is not their perfect fit, so make sure you get measured, which can be easily done in a lingerie shop.
Smoking makes the skin lose its natural elasticity, which causes the breasts to drop. It reduces the amount of collagen in the skin and worsens the blood circulation. This makes the skin become weaker and age faster.