If you care about your health, then do not wear a bra. Research shows that wearing bras is a leading cause of breast disease, including cysts, pain, and cancer. It also causes the breasts to droop, since the artificial support of the bra causes the natural suspensory ligaments in the breasts to weaken and atrophy from non-use, similar to how putting your arm in a sling makes your shoulder muscles weaken. In general, don’t wearing any tight clothing, since this can interfere with circulation. Bras are too tight if they cause red marks or indentations in the skin. If you do choose to wear one, do not wear it for more than 12 hours daily, massage your breasts after removing it, and never sleep in it. Avoid underwires, push-up bras, and synthetic fabrics.
I also suggest you ask yourself why you would want to wear a bra. There is no biological reason for wearing one, since the breasts were not designed by nature with some flaw that requires 20th Century lingerie for support. It’s only about fashion, and fashions can be unhealthy. Fortunately, being bra-free is now fashionable, too. Women are questioning why they need to hide their nipples and bind their breasts, while men are free to be themselves. When you add the health risks of constricting the breasts with a bra, the question is why any woman would want to subject herself to the discomfort and hazards of bras.
By the way, breast size is not really an issue. In cultures where there are no bras, there are women with large breasts that are healthy, perky, and without any cysts, pain, or lumps. And breast cancer in bra-free cultures is a rarity.
Large breasts do not cause back pain—that pain is caused by the weight of the breasts being transferred to the bra. Notice how large breasted women have deep grooves in their shoulders from the weight of the breasts pulling down on the bra’s shoulder straps. Research has shown this can cause numbness and tingling in the hands from nerve compression. It also causes headaches, hunched back, shoulder pain, and back pain. Of course, if you have been wearing a bra and you have large breasts, then your body may be reliant on the bra for support, making you feel uncomfortable without a bra. It takes a little time to wean yourself off of the bra, but women who have done this feel healthier and their breasts lift and tone. Keep in mind, too, that the bra causes the breasts to feel heavier and more painful because of the fluid accumulation from lymphatic impairment. This, too, goes away once the constriction ends.