Body fat levels linked to breast cancer risk in post-menopausal women

Older women with excess body fat, even if they have what's considered a normal body-mass index, could be at ...

Posted: Dec 11, 2018 2:27 AM
Updated: Dec 11, 2018 2:27 AM

Older women with excess body fat, even if they have what's considered a normal body-mass index, could be at greater risk for breast cancer, according to a study published Thursday in the medical journal JAMA Oncology.

"We do find that excess body fat in those who are post-menopausal with a normal body mass index is associated with about a doubling in the risk of estrogen-dependent breast cancer," said Dr. Andrew Dannenberg, one of the study's authors and director of cancer prevention at the Sandra and Edward Meyer Cancer Center at Weill Cornell Medicine.

Breast cancer

Cancer

Diseases and disorders

Health and medical

Medical fields and specialties

Oncology

Diet and nutrition

Diet, nutrition and fitness

Obesity

Health and health care (by demographic group)

Menopause

Women's health

The American Cancer Society says estrogen-dependent cancers, called ER-positive breast cancer in the study, occur when the receptor proteins in or on cells attach to the hormone estrogen and rely on it to grow.

The researchers studied 3,460 American women between the ages of 50 and 79 who had gone through menopause. The women were part of the Women's Health Initiative and had their body composition measured at the beginning of that program, Dannenberg said. Of those women, 146 developed ER-positive breast cancer, and the researchers looked for a relationship between excess body fat and the development of this cancer.

They found that a 5-kilogram (11-pound) increase in whole-body fat mass was associated with a 35% increased risk of this kind of breast cancer. A 5-kilogram increase in fat mass of the trunk was associated with a 56% increase in risk.

Trunk fat is "defined by the fat contained in the torso apart from head and limbs," according to the study.

The study also found that for invasive breast cancer, which has spread into the surrounding breast tissue, a 5-kilogram increase in whole-body fat mass was related to a 28% risk increase. The same increase in trunk fat was tied to a 46% increase in the risk of invasive breast cancer.

"The main takeaway is that having excess body fat, even when you have a normal body mass index, is associated with an increased risk for breast cancer," Dannenberg said.

A person's BMI is calculated through a formula involving their height and weight; a "normal" BMI is considered to be between 18.5 and 24.9, according to the study.

The researchers also looked at blood data taken at the start of the Women's Health Initiative for other factors that are known to play a part in the development of breast cancer, such as elevation of insulin molecules.

The results "highlight the importance of research differentiating the contributions of body size, body composition, and metabolic profiles to breast cancer risk," Drs. Isabel Pimentel, Ana Elisa Lohmann and Pamela J. Goodwin wrote in an editorial published alongside the study.

The editorial authors also point out that other researchers have looked into the subject with differing results and note that "these observations suggest that components of metabolic health, rather than the presence of full metabolic syndrome, may contribute to breast cancer risk."

A particular strength of the research for Hoda Anton-Culver, distinguished professor in the Department of Medicine at the University of California, Irvine, was the analysis of the location on the body of the fat levels.

"I think it's a good step forward that takes us from looking at the BMI as an indicator of obesity to really looking at the particular site of the fat concentration in the body," said Anton-Culver, who was not involved in the research.

Scientists have known that there was an association between obesity and cancer, but Anton-Culver says the new study moves the research beyond that general association.

"They say it correctly in the summary, that obesity is associated with breast cancer, but more specifically, obesity around the abdomen is more specific for that association," she said.

Although Anton-Culver thinks the research is strong, she pointed out that it looked only at a specific cancer.

"I don't know if we look at the same issues with other cancers as the outcome, what it's going to be, is it specific to breast cancer?" she said. "We need to ask that question next, because obesity is a risk factor for other cancers."

Mississippi Coronavirus Cases

Data is updated nightly.

Cases: 296154

Reported Deaths: 6764
CountyCasesDeaths
DeSoto19700230
Hinds18851392
Harrison16736281
Rankin12757265
Jackson12623228
Lee9694161
Madison9480203
Jones7990147
Forrest7234138
Lauderdale6837226
Lowndes6032140
Lamar589680
Lafayette5740113
Washington5220130
Bolivar4616124
Oktibbeha441593
Panola431995
Pearl River4178131
Warren4134115
Pontotoc410571
Marshall403592
Monroe3990127
Union396174
Neshoba3817169
Lincoln3552104
Hancock348975
Leflore3380118
Sunflower318986
Tate303174
Pike301296
Scott294570
Alcorn292263
Yazoo290565
Itawamba290175
Coahoma281169
Tippah279265
Copiah278758
Simpson276280
Prentiss270258
Wayne254341
Leake252871
Marion252778
Covington249580
Grenada247878
Adams234678
George232145
Newton230852
Winston221877
Jasper213645
Tishomingo212665
Attala206669
Chickasaw201453
Holmes182370
Clay179251
Stone172429
Tallahatchie171239
Clarke169371
Calhoun158028
Smith153033
Yalobusha145036
Greene127833
Walthall124340
Noxubee122831
Montgomery122639
Perry122135
Lawrence120321
Carroll118625
Amite111734
Webster110832
Jefferson Davis102231
Tunica99323
Claiborne98829
Benton93824
Humphreys92927
Kemper90323
Quitman77414
Franklin76119
Choctaw69817
Jefferson62727
Wilkinson62426
Sharkey49117
Issaquena1676
Unassigned00

Alabama Coronavirus Cases

Cases: 497154

Reported Deaths: 10029
CountyCasesDeaths
Jefferson714001387
Mobile36252736
Madison32573462
Tuscaloosa24289414
Montgomery22708519
Shelby22112215
Baldwin19856285
Lee15021155
Calhoun13755288
Morgan13742252
Etowah13379320
Marshall11439210
Houston10110262
Elmore9451185
Limestone9413136
St. Clair9003225
Cullman8979182
Lauderdale8610212
DeKalb8486175
Talladega7582165
Walker6571259
Jackson6542103
Autauga631391
Blount6229127
Colbert5998120
Coffee5259103
Dale4657107
Russell406433
Franklin399778
Covington3989106
Chilton3891100
Escambia378772
Tallapoosa3613143
Clarke343953
Chambers3423111
Dallas3419142
Pike293372
Marion288895
Lawrence284683
Winston258668
Bibb245960
Geneva240270
Marengo238357
Pickens225055
Barbour212951
Hale211969
Fayette201357
Butler201166
Henry182941
Cherokee177739
Monroe166639
Randolph164640
Washington156635
Macon147243
Crenshaw146254
Clay145554
Cleburne139741
Lamar133733
Lowndes132551
Wilcox122525
Bullock117236
Conecuh107024
Perry105927
Sumter99432
Coosa89624
Greene88532
Choctaw55123
Out of AL00
Unassigned00
Tupelo
Clear
62° wxIcon
Hi: 72° Lo: 36°
Feels Like: 62°
Columbus
Clear
60° wxIcon
Hi: 71° Lo: 36°
Feels Like: 60°
Oxford
Clear
54° wxIcon
Hi: 72° Lo: 33°
Feels Like: 54°
Starkville
Clear
52° wxIcon
Hi: 71° Lo: 35°
Feels Like: 52°
WTVA Radar
WTVA Temperatures
WTVA Severe Weather