The Who, What, Where, When and Sometimes, Why.

Body weight and breast cancer risk

This summary table contains detailed information about research studies. Summary tables are a useful way to look at the science behind many breast cancer guidelines and recommendations. However, to get the most out of the tables, it’s important to understand some key concepts. Learn how to read a research table.

Introduction: Body weight affects breast cancer risk differently for premenopausal and postmenopausal women.

  • Before menopause, being overweight or obese modestly decreases breast cancer risk.
  • After menopause, being overweight or obese increases breast cancer risk.

Learn more about body weight and breast cancer risk.

Learn about body weight and breast cancer survival.

Learn about the strengths and weaknesses of different types of studies.

See how this risk factor compares with other risk factors for breast cancer.

Study selection criteria: Prospective cohort studies with at least 1,000 breast cancer cases and at least 5 years of follow-up, pooled analyses and meta-analyses

Table notes: In the studies below, researchers use a measure called body mass index (BMI) to estimate body fat. BMI takes into account height and weight. Calculate your BMI.

For people ages 20 and older, weight status categories are:

BMI

Body weight status

18.5 to 24.9

Normal

25.0 to 29.9

Overweight

30.0 and greater

Obese

Relative risk above 1 indicates increased risk. Relative risk below 1 indicates decreased risk.

Women who use menopausal hormone therapy (MHT) have an increased risk of breast cancer. This increased risk may mask an increased risk from body weight. For this reason, many studies report findings by MHT use. MHT may also be called postmenopausal hormone therapy or hormone replacement therapy (HRT).

Learn more about MHT and breast cancer risk.

 

Study

Study Population
(number of participants)

Follow-up
(years)

Comparisons of Body Mass Index (BMI)

Relative Risk of Breast Cancer in Heavier Women Compared to Leaner Women, by Menopausal Status
RR (95% CI)

Before
Menopause

After
Menopause

Prospective cohort studies

Breast Cancer Surveillance Consortium [1]

1,279,443
(18,576 cases)

8

25-29.9
vs.
18.5-24.9

For estrogen receptor-positive (ER-positive) tumors:
1.08
(1.03-1.14)

For estrogen receptor-negative (ER-negative) tumors:
1.28
(1.14-1.44)

 

For ER-positive tumors:
1.28
(1.21-1.35)†

For ER-negative tumors:
1.17
(1.06-1.30)†

 

 

 

 

30-34.9
vs.
18.5-24.9

 

For ER-positive tumors:
1.15
(1.06-1.25)

For ER-negative tumors:
1.48
(1.25-1.77)

 

 

For ER-positive tumors:
1.53
(1.41-1.66)†

For ER-negative tumors:
1.38
(1.16-1.63)†

 

Akinyemiju et al. [2]

189,742
(12,698 cases)

16-17

24.9-30
vs.
18.5-25

 

1.08
(1.05-1.10)‡

Tretli et al. [3]

567,333
(8,427 cases)

18

Very small differences in BMI

0.84
(0.74-0.95)

1.16
(1.09-1.23)

Million Women Study (UK) [4]

1,222,630
(6,808 cases)

5

30 or more
vs.
Less than 23

0.79
(0.68-0.92)

1.29
(1.22-1.36)

Korean Cancer Prevention Study [5]

443,273
(3,973 cases)

11

25-29.9
vs.
23-24.9

 

1.18
(1.04-1.34)§

 

 

 

30 or more
vs.
23-24.9

 

1.13
(0.84-1.53)§

California Teachers Study [6]

109,862
(3,844 cases)

13-14

25 or more 
vs.
Less than 25

0.94
(0.71-1.24)||

1.21
(1.07-1.37)||,¶

Women’s Health Initiative [7]

67,142
(3,388 cases)

13

25-29.9
vs.
23-24.9

 

1.17
(1.06-1.29)**

   

30-34.9
vs.
23-24.9

 

1.37
(1.23-1.53)**

Multiethnic Cohort Study [8]

82,971
(3,080 cases)

8-11

25-29.9
vs.
20-24.9

 

1.35
(1.17-1.57)††

   

30 or more
vs.
20-24.9

 

1.60
(1.36-1.87)††

UK Biobank [9]

162,691
(2,913 cases)

6

27-29.9
vs.
15-24

 

1.32
(1.18-1.47)

 

 

 

30 or more 
vs.
15-24

 

1.52
(1.36-1.70)

Nurses’ Health Study [10]

95,256
(2,517 cases)

16

More than 31 vs.
20 or less

0.62
(0.45-0.86)

1.59
(1.09-2.32)¶

PLCO Cancer Screening Trial [11]

70,575
(2,063 cases)

5

25-29.9
vs.
18.5-24.9

 

1.06
(0.95-1.17)

   

 30-34.9
vs.
18.5-24.9

 

1.10
(0.97-1.26)

   

35 or more
vs.
18.5-24.9

 

1.21
(1.02-1.43)

Canadian National Breast Screening Study [12]

40,318
(1,673 cases)

16

30 or more
vs.
Less than 25

1.01
(0.74-1.37)

1.26
(0.95-1.67)

Lundqvist et al. [13]

36,490
(1,637 cases)

26

30 or more
vs.
18.5-25

0.8
(0.4-1.3)

1.3
(1.0-1.7)

E3N Women’s Cohort Study—France [14]

94,805
(1,522 cases)

10

30 or more
vs.
18.5-25

0.66
(0.40-1.10)

1.17
(0.89-1.57)¶

Tornberg et al. [15]

47,003
(1,466 cases)

25

28 or more
vs.
Less than 22

0.41Sig

1.13Sig

Nurses’ Health Study II [16]

113,130
(1,398 cases)

14

30 or more
vs.
Less than 20

0.81
(0.68-0.96)

 

Swedish Mammography Screening Cohort [17]

51,823
(1,188 cases)

8

30 or more
vs.
18.5-24.9

 

1.38
(1.07-1.77)¶

Shanghai Women’s Health Study [18]

68,253
(1,162 cases)

15

30 or more
vs.
185-22.9

0.98
(0.62-1.57)

2.43
(1.73-3.40)

Cancer Prevention Study-II (CPS-II) [19]

28,965
(1,088 cases)

12

25-29.9
vs.
Less than 25

 

1.26
(1.07-1.48)

 

 

 

30 or more
vs.
Less than 25

 

1.40
(1.10-1.78)

Black Women’s Health Study [20]

52,080
(1,062 cases)

10

35 or more
vs.
Less than 25

1.35
(0.53-3.47)

0.78
(0.58-1.05)

Vorarlberg Health Monitoring and Promotion Program-Austria [21]

78,484
(1,045 cases)

10

35 or more
vs.
18.5-24.9

 

1.01
(0.72-1.42)‡‡

Pooled and meta-analyses

van den Brandt et al. [22]

337,819
(4,385 cases)

 

30 or more
vs.
Less than 21

0.58
(0.34-1.00)

1.27
(1.03-1.55)

Research Group for the Development and Evaluation of Cancer Prevention Strategies in Japan [23]

183,940
(1,783 cases, studies of Japanese women only)

 

30 or more
vs.
23-24.9

1.80
(0.81-3.99)

1.26
(0.92-1.72)

Chen et al. [24]

18 studies

 

Highest BMI
vs.
Lowest BMI

0.94
(0.81-1.11)

 

 

26 studies

 

Highest BMI
vs. 
Lowest BMI

 

1.33
(1.20-1.48)

Cheraghi et al. [25]

8 studies

 

25-29.9
vs.
18.5-24.9

1.01
(0.77-1.31)

1.12
(1.06-1.18)

   

30 or more
vs.
18.5-24.9

0.91
(0.71-1.18)

1.16
(1.08-1.25)

Suzuki et al. [26]

4 studies

 

Highest BMI vs.
Average BMI

 

For hormone receptor-positive tumors:
1.74
(1.34-2.25)

For hormone receptor-negative tumors:
0.90
(0.53-1.52)

Sig = Results were statistically significant.

† Relative risk for women not currently using MHT. Among MHT users, those with a higher BMI had an increased risk of ER-positive breast cancer, but not ER-negative breast cancer.

‡ Relative risk for all postmenopausal women. Among African-American women, relative risk was 1.05 (0.94-1.17) and among white women, relative risk was 1.07 (1.04-1.09).

§ Includes pre- and postmenopausal women.

|| All breast cancers were estrogen receptor-positive.

¶ Relative risk for women who never used MHT. Among MHT users, there was no increase in risk.

** Relative risk for all women. Among women who never used MHT (estrogen plus progestin) or who used MHT in the past, there was no increase in risk. Among current MHT users, there was an increase in risk for overweight and obese women.

†† Relative risk for women who never used MHT. Relative risks among former MHT users were similar. Among current MHT users, there was no increase in risk.

‡‡ Combined premenopausal and postmenopausal breast cancer risk. For women 65 and older, the relative risk for BMI 30-34.9 vs. 18.5-24.9 was 1.48 (1.12-1.95).  

References

  1. Kerlikowske K, Gard CC, Tice JA, et al. for the Breast Cancer Surveillance Consortium. Risk factors that increase risk of estrogen receptor-positive and -negative breast cancer. J Natl Cancer Inst. 109(5):djw276, 2017.
  2. Akinyemiju T, Wiener H, Pisu M. Cancer-related risk factors and incidence of major cancers by race, gender and region; analysis of the NIH-AARP diet and health study. BMC Cancer. 17(1):597, 2017. 
  3. Tretli S. Height and weight in relation to breast cancer morbidity and mortality. A prospective study of 570,000 women in Norway. Int J Cancer. 44:23-30, 1989.
  4. Reeves GK, Pirie K, Beral V, Green J, Spencer E, Bull D. Cancer incidence and mortality in relation to body mass index in the Million Women Study: cohort study. BMJ. 335(7630):1134, 2007.
  5. Jee SH, Yun JE, Park EJ, et al. Body mass index and cancer risk in Korean men and women. Int J Cancer. 123(8):1892-6, 2008.
  6. Horn-Ross PL, Canchola AJ, Bernstein L, Neuhausen SL, Nelson DO, Reynolds P. Lifetime body size and estrogen-receptor-positive breast cancer risk in the California Teachers Study cohort. Breast Cancer Res. 18(1):132, 2016.
  7. Neuhouser ML, Aragaki AK, Prentice RL, et al. Overweight, obesity, and postmenopausal invasive breast cancer risk: a secondary analysis of the Women’s Health Initiative randomized clinical trials. JAMA Oncol. 1(5):611-21, 2015.
  8. White KK, Park SY, Kolonel LN, Henderson BE, Wilkens LR. Body size and breast cancer risk: The multiethnic cohort. Int J Cancer. 131(5):E705-16, 2012.
  9. Guo W, Key TJ, Reeves GK. Adiposity and breast cancer risk in postmenopausal women: results from the UK Biobank prospective cohort. Int J Cancer. 143(5):1037-1046, 2018.
  10. Huang Z, Hankinson SE, Colditz GA, et al. Dual effects of weight and weight gain on breast cancer risk. JAMA. 278(17):1407-1411, 1997.
  11. Lacey JV Jr, Kreimer AR, Buys SS, et al. for the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial Project Team. Breast cancer epidemiology according to recognized breast cancer risk factors in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial Cohort. BMC Cancer. 9:84, 2009.
  12. Silvera SAN, Jain M, Howe GR, et al. Energy balance and breast cancer risk: a prospective cohort study. Breast Cancer Res Treat. 97(1):97-106, 2006.
  13. Lundqvist E, Kaprio J, Verkasalo PK, et al. Co-twin control and cohort analyses of body mass index and height in relation to breast, prostate, ovarian, corpus uteri, colon and rectal cancer among Swedish and Finnish twins. Int J Cancer. 121(4):810-8, 2007.
  14. Tehard B, Lahmann PH, Riboli E, Clavel-Chapelon F. Anthropometry, breast cancer and menopausal status: Use of repeated measurements over 10 years of follow-up-results of the French E3N women’s cohort study. Int J Cancer. 111(2):264-9, 2004.
  15. Tornberg SA and Carstensen JM. Relationship between Quetelet’s Index and cancer of breast and female genital tract in 47,000 women followed for 25 years. Br J Cancer. 69:358-361, 1994.
  16. Michels K, Terry KL, Willett WC. Longitudinal study on the role of body size in premenopausal breast cancer. Arch Intern Med. 166(21):2395-402, 2006.
  17. Suzuki R, Rylander-Rudqvist T, Ye W, et al. Body weight and postmenopausal breast cancer risk defined by estrogen and progesterone receptor status among Swedish women: A prospective cohort study. Int J Cancer. 119(7):1683-9, 2006.
  18. Liu Y, Warren Andersen S, Wen W, et al. Prospective cohort study of general and central obesity, weight change trajectory, and risk of major cancers among Chinese women. Int J Cancer. 139(7):1461-70, 2016.
  19. Gaudet MM, Carter BD, Patel AV, Teras LR, Jacobs EJ, Gapstur SM. Waist circumference, body mass index, and postmenopausal breast cancer incidence in the Cancer Prevention Study-II Nutrition Cohort. Cancer Causes Control. 25(6):737-45, 2014.
  20. Palmer JR, Adams-Campbell LL, Boggs DA, Wise LA, Rosenberg L. A prospective study of body size and breast cancer in black women. Cancer Epidemiol Biomarkers Prev. 16(9):1795-802, 2007.
  21. Rapp K, Schroeder J, Klenk J, et al. Obesity and incidence of cancer: a large cohort study of over 145,000 adults in Austria. Br J Cancer. 93(9):1062-7, 2005.
  22. van den Brandt PA, Spiegelman D, Yaun S, et al. Pooled analysis of prospective cohort on height, weight, and breast cancer risk. Am J Epidemiol. 152(6):514-527, 2000.
  23. Wada K, Nagata C, Tamakoshi A, et al. for the Research Group for the Development and Evaluation of Cancer Prevention Strategies in Japan. Body mass index and breast cancer risk in Japan: a pooled analysis of eight population-based cohort studies. Ann Oncol. 25(2):519-24, 2014.
  24. Chen Y, Liu L, Zhou Q, et al. Body mass index had different effects on premenopausal and postmenopausal breast cancer risks: a dose-response meta-analysis with 3,318,796 subjects from 31 cohort studies. BMC Public Health. 17(1):936, 2017.
  25. Cheraghi Z, Poorolajal J, Hashem T, Esmailnasab N, Doosti Irani A. Effect of body mass index on breast cancer during premenopausal and postmenopausal periods: a meta-analysis. PLoS One. 7(12):e51446, 2012.
  26. Suzuki R, Orsini N, Saji S, Key TJ, Wolk A. Body weight and incidence of breast cancer defined by estrogen and progesterone receptor status–a meta-analysis. Int J Cancer. 124(3):698-712, 2009. 

 

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Komen Perspectives

Read Komen’s perspective on body weight and breast cancer risk.*

* Please note, the information provided within Komen Perspectives articles is only current as of the date of posting. Therefore, some information may be out of date at this time.    

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