Having a sweet tooth may increase breast cancer risk

26 June 2014

Toronto -

A diet high in sweet foods and sugar-sweetened drinks is associated with increased breast density, according to a new study funded in part by the Canadian Cancer Society. Increased breast density is a well-established risk factor for breast cancer. Some studies have shown that women with dense breast tissue in 75% or more of their breasts have a 4 to 6 times greater risk of breast cancer than women with little or no dense breast tissue.

The study, which involved 776 premenopausal and 779 postmenopausal women, found that postmenopausal women with a high intake of sweet foods and premenopausal women with a high intake of sugar-sweetened beverages had higher breast density. The findings mark the first time a specific association has been studied between diets high in sweet foods and drinks, breast density and menopausal status.

“We know that the worldwide consumption of sugar has increased and the findings of this study show what effect that type of diet has on breast density, one of the strongest indicators for breast cancer risk,” says study lead author Dr Caroline Diorio, professor in the department of social and preventive medicine at Université Laval. “As this is an understudied area, we need more research to further understand the health implications of a diet high in sugar.”

In this study, breast density was measured through mammography screening. Women from both groups answered a questionnaire about the frequency of their consumption of sweet foods, such as chocolates, doughnuts, pies and pastries; sugar-sweetened beverages, such as carbonated drinks with sugar and sweetened fruit juice; and spoonfuls of sugar added to food or drinks.

The results of the questionnaire found an association between the consumption of sugar-sweetened beverages and breast density in premenopausal women. The same association with breast density was noted for sweet foods consumed by postmenopausal women. Women who had more than 3 servings of sugar-sweetened beverages in a week had a 3% difference in breast density compared to those who did not have this type of beverage, which could be considered a significant difference. The researchers suggest that this association may be greater in populations that consume more sugar.

Dense breasts have larger amounts of connective, gland and milk duct tissues than fatty tissue. Research suggests that the intake of sweet items could enhance cell growth and, therefore, density in breast tissues.

The study was published in the open-access journal BMC Public Health.

Through our generous donors and gold-standard peer-review process, the Canadian Cancer Society funds the best cancer research in Canada. Our funded researchers work in universities, hospitals and research centres across the country and are mapping new ways to change cancer forever. For more information, visit cancer.ca or call our toll-free, bilingual Cancer Information Service at 1-888-939-3333 (TTY 1-866-786-3934).

For more information, please contact:

Brooke Kelly

Communications Coordinator

Canadian Cancer Society

National office

Phone: 416-934-5321