Breastfeeding cuts breast cancer risk
26 July 2002
The longer women breastfeed and the more children they have, the less likely they are to develop breast cancer, a UK study has confirmed.
'The relative risk of breast cancer is reduced by 4.3 per cent for each year that a woman breastfeeds, in addition to a reduction of 7 per cent for each birth,' the researchers wrote in The Lancet (2002; 360: 187-95).
Relative risk is the ratio of risk of disease among people exposed to a risk factor (for example, breastfeeding) to the risk among people not exposed to the risk factor.
Data from 50,302 women with invasive breast cancer and 96,973 healthy women were collected from 30 countries.
Confounding factors (those that may also have an effect and confuse the issue), including family history, age of starting periods (menarche), body mass index, the use of hormonal contraceptives, and alcohol or tobacco use did not alter the breastfeeding effect on the relative risk of breast cancer, the researchers said.
But they said there was no distinction between exclusive breastfeeding and breastfeeding with supplementary feeds.
Last Reviewed: 26 July 2002
- 1. Medical Observer Weekly 26/7/02
