A new study suggests that increased breast size by the age of 20 may signify a higher risk for diabetes in mid-life. Data was gathered from Nurses Health Study 11 to show that the correlation does exist. The relationship between breast size and diabetes can be explained as follows: too much fat might elevate the estrogen level, resulting in breast size increase. Therefore the solution to the problem might be a hormonal level check. And the first change that needs to take place is weight loss.