Obesity not linked to breast cancer in Mexican-American women

Nov 08, 2010

Obesity was not associated with breast cancer risk in Mexican-American women, even when measured at numerous ages throughout a woman's lifetime, according to data presented at the Ninth Annual AACR Frontiers in Cancer Prevention Research Conference, held here Nov. 7-10, 2010.

However, data did show that weight gain during adulthood seemed to reduce , regardless of menopausal status.

"We found that for every 5 kg of weight gain there was a significant 8 percent decrease in the risk for breast cancer," said Krystal Sexton, Ph.D., a Susan G. Komen Fellow in breast cancer disparities research at The University of Texas Health Science Center at Houston School of Public Health. "However, it is important that we do not send a message that gaining weight prevents breast cancer."

Instead, Sexton and colleagues in the department of epidemiology at The University of Texas MD Anderson Cancer Center, are hypothesizing that the reduced risk for breast cancer among overweight and obese Mexican-American women may be due to a shorter lifetime exposure to estrogen, which is associated with breast cancer.

Previous research has shown that in Mexican-American women there is an association between obesity and earlier age of menopause.

"Women in our study who did not have breast cancer were actually experiencing menopause at an earlier age — especially women who were overweight and obese — compared with women who were overweight and obese and did have breast cancer," Sexton said.

This earlier onset of menopause exposed overweight and obese women to two fewer years of estrogen throughout their lifetimes, possibly putting them at a lower risk for breast cancer, according to Sexton.

The researchers identified 155 Mexican-American women with breast cancer and compared them with 333 women of similar ages without breast cancer. Patients reported their weights at ages 15, 30 and at cancer diagnosis. They also reported between age 15 and diagnosis.

Unlike research in non-Hispanic white women, which has shown an increased risk for breast cancer in obese postmenopausal women, there was no association between body mass index and breast cancer in Mexican-American women, regardless of menopausal status.

"We know that Hispanic women have a lower incidence of , but they continue to be diagnosed with breast cancers that have larger tumor sizes, more advanced cancer stages and poorer prognostic factors, leading to lower survival rates compared to non-Hispanic white women," Sexton said. "There is a real need to continue to try to understand why these disparities exist."

Explore further: Six percent of colorectal cancer found to be interval tumors

add to favorites email to friend print save as pdf

Related Stories

Weight gain increases breast cancer risk

Jul 13, 2006

Women who gain weight as young adults have a greater risk of developing breast cancer after menopause than women who maintain or lose weight, a study says.

Breast cancer more aggressive among obese women

Mar 14, 2008

Women with breast cancer have more aggressive disease and lower survival rates if they are overweight or obese, according to findings published in the March 15 issue of Clinical Cancer Research, a journal of the American Associ ...

Breast cancer risk factors differ among races

Apr 26, 2010

A new study finds that factors known to increase the risk of breast cancer among white women have less influence in Hispanic women. Published early online in Cancer, a peer-reviewed journal of the American Cancer Societ ...

Recommended for you

Unraveling the 'black ribbon' around lung cancer

3 hours ago

It's not uncommon these days to find a colored ribbon representing a disease. A pink ribbon is well known to signify breast cancer. But what color ribbon does one think of with lung cancer?

Survival hope for melanoma patients thanks to new vaccine

8 hours ago

(Medical Xpress)—University of Adelaide researchers have discovered that a new trial vaccine offers the most promising treatment to date for melanoma that has spread, with increased patient survival rates and improved ability ...

User comments : 0

More news stories

Turning off depression in the brain

Scientists have traced vulnerability to depression-like behaviors in mice to out-of-balance electrical activity inside neurons of the brain's reward circuit and experimentally reversed it – but there's ...

Is Parkinson's an autoimmune disease?

The cause of neuronal death in Parkinson's disease is still unknown, but a new study proposes that neurons may be mistaken for foreign invaders and killed by the person's own immune system, similar to the ...