WEIGHT GAIN

Theory:

The more weight a woman gains in adult life, the higher her risk of breast cancer after menopause. This is probably because fat tissue becomes your main source of oestrogen after you’ve been through the menopause; the more fat you have, the more oest rogen you produce.

Research has found that a woman of 5ft 4in who puts on just over 2st between the ages of 20 and 50 is almost twice as likely to develop the disease.
Expert Comment:

Keeping a healthy body weight is one of the best ways of reducing the risk of breast cancer. Fat is not inactive - it’s actually pumping out hormones and other chemicals that can affect your risk of disease.

Evidence for Link: STRONG