This summary table contains detailed information about research studies. While viewing summary tables offers an informative glimpse at the science behind many breast cancer guidelines and recommendations, they should be viewed with some caution. There are a number of concepts you must understand to be able to successfully read and interpret research tables. To get some background information about understanding research tables, please see How to Read a Research Table.
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Introduction: Carotenoids are natural orange-red food pigments. Many carotenoids are antioxidants that can be converted into vitamin A. Beta-carotene is one example of a carotenoid. As the studies below show, there is some evidence from cohort and case-control studies that a high intake of carotenoids may protect against breast cancer. Studies have also looked at the link between blood levels of carotenoids (is a marker for the amount of carotenoids consumed) and breast cancer risk. Though the results are not completely consistent, most studies on blood levels of carotenoids suggest that a high intake of carotenoids decreases risk of breast cancer.
It is worth noting, though, that eating too much of certain carotenoids may have some risk. Several studies have found that taking a daily supplement of the carotenoid beta-carotene can increase the risk of both lung cancer and premature death in smokers [1,2]. In general, fruits and vegetables are the best sources of carotenoids and are part of a healthy diet.
Find more information on 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: For dietary intake studies: All available prospective cohort studies, nested case-control studies and case-control studies with at least 400 breast cancer cases. For blood level studies: All available nested case-control studies with at least 100 cases.
Table note: Relative risk above 1 indicates increased risk. Relative risk below 1 indicates decreased risk.
Study
|
Study Population
(number of participants)
|
Follow-up
(years)
|
Relative Risk of Breast Cancer in Women With a High Intake of Beta-Carotene Compared to Women With a Low Intake,
RR (95% CI)
|
DIETARY INTAKE OF CAROTENOIDS
|
Prospective cohort studies
|
Women’s Health Initiative Observational Study [3]
|
84,805
(2,879 cases)
|
7.6 |
0.86 (0.75-0.99) |
| Nurses' Health Study [4] |
83,234
(2,697 cases)
|
14 |
0.83 (0.66-1.04)* |
Swedish Mammography Screening Cohort [5]
|
59,036
(1,271 cases)
|
10 |
1.01 (0.84-1.22) |
| Iowa Women's Health Study [6] |
34,387
(879 cases)
|
6 |
1.17 (0.87-1.56) |
Nurses' Health Study II [7]
|
90,655
(714 cases)
|
8
|
0.96 (0.75-1.22)
|
Nested case-control studies
|
| |
Cases
|
Controls
|
|
|
Canadian National Breast Screening Study [8]
|
1,452
|
5,239
|
9.5
|
1.01 (0.70-1.33)
|
Netherlands Cohort Study [9]
|
650
|
1,066
|
4.3
|
1.01 (0.72-1.42)
|
Case-control studies
|
Bohlke et al. [10]
|
820
|
1,548
|
NA
|
0.67 (0.49-0.91)
|
Potischman et al. [11]
|
568
|
1,451
|
NA
|
0.96 (0.70-1.30)
|
Rohan et al. [12]
|
451
|
326
|
NA
|
0.76 (0.50-1.18)
|
Graham et al. [13]
|
439
|
494
|
NA
|
0.56 (0.38-0.82)†
|
Nkondjock & Ghadirian [14]
|
414
|
429
|
NA
|
0.99 (0.67-1.48)‡
|
BLOOD LEVELS OF CAROTENOIDS
|
Nested case-control studies
|
| |
Cases
|
Controls
|
|
|
Nurses' Health Study [15]
|
969
|
969
|
22
|
0.73 (0.53-1.02)§
|
Women's Health Study [16]
|
508
|
508
|
9.9
|
1.36 (0.79-2.33)
|
Sato et al. [17]
|
295
|
295
|
4.3
|
0.41 (0.22-0.79)
|
New York University Women's Health Study [18]
|
270
|
270
|
up to 10
|
0.45 (0.26-0.77)
|
Hulten et al. [19]
|
201
|
290
|
up to 10
|
0.8 (0.5-1.4)
|
Dorgan et al. [20]
|
105
|
203
|
2.7
|
1.1 (0.5-2.4)
|
NA = Not applicable.
* Premenopausal women only.
† Postmenopausal women only.
‡ Highest vs. lowest level of total carotenoid intake also did not significantly reduce breast cancer risk (0.96 (0.65-1.43)).
§ While highest vs. lowest level of total carotenoid intake also did not significantly reduce breast cancer risk (0.76 (0.55-1.05)), there was a significant trend of decreasing breast cancer risk with increasing levels of both beta-carotene intake and total carotenoid intake.
References
1. The Alpha-Tocopherol, Beta Carotene Cancer Prevention Study Group. The effect of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers. N Engl J Med. 330:1029 –35, 1994.
2. Omenn GS, Goodman G, Thornquist M, et al. Chemoprevention of lung cancer: the beta-Carotene and Retinol Efficacy Trial (CARET) in high-risk smokers and asbestos-exposed workers. IARC Sci Publ: 67-85, 1996.
3. Cui Y, Shikany JM, Liu S, Shagufta Y, Rohan TE. Selected antioxidants and risk of hormone receptor-defined invasive breast cancers among postmenopausal women in the Women's Health Initiative Observational Study. Am J Clin Nutr. 87(4):1009-18, 2008.
4. Zhang S, Hunter DJ, Forman MR, et al. Dietary carotenoids and vitamins A, C and E, and risk of breast cancer. J Natl Cancer Inst. 91(6):547-56, 1999.
5. Michels KB, Holmberg L, Bergkvist L, et al. Dietary antioxidant vitamins, retinol, and breast cancer incidence in a cohort of Swedish women. Int J Cancer. 91(4):563-7, 2001.
6. Kushi LH, Fee RM, Sellers TA, et al. Intake of vitamins A, C, and E and postmenopausal breast cancer. The Iowa Women's Health Study. Am J Epidemiol. 144(2):165-74, 1996.
7. Cho E, Spiegelman D, Hunter DJ, Chen WY, Zhang SM, Colditz GA, Willett WC. Premenopausal intakes of vitamins A, C, and E, folate, and carotenoids, and risk of breast cancer. Cancer Epidemiol Biomarkers Prev. 12(8):713-20, 2003.
8. Terry P, Jain M, Miller AB, Howe GR, Rohan TE. Dietary carotenoids and risk of breast cancer. Am J Clin Nutr. 76(4);883-8, 2002.
9. Verhoeven DT, Assen N, Goldbohm RA, et al. Vitamins C and E, retinol, beta-carotene and dietary fibre in relation to breast cancer risk: a prospective cohort study. Br J Cancer. 75(1):149-55, 1997.
10. Bohlke K, Spiegelman D, Trichopoulou A, et al. Vitamins A, C and E, and the risk of breast cancer: results from a case-control study in Greece. Br J Cancer. 79(1):23-9, 1999.
11. Potischman N, Swanson CA, Coates RJ, et al. Intake of food groups and associated micronutrients in relation to risk of early-stage breast cancer. Int J Cancer. 82(3):315-21, 1999.
12. Rohan TE, McMichael AJ, Baghurst PA. A population-based case-control study of diet and breast cancer in Australia. American Journal of Epidemiology. 128(3):478-89, 1988.
13. Graham S, Hellmann R, Marshall J, et al. Nutritional epidemiology of postmenopausal breast cancer in Western New York. Am J Epidemiol. 134(6):552-66, 1991.
14. Nkondjock A, Ghadirian P. Intake of specific carotenoids and essential fatty acids and breast cancer risk in Montreal, Canada. Am J Clin Nutr. 79(5):857-64, 2004.
15. Tamimi RM, Hankinson SE, Campos H, et al. Plasma carotenoids, retinol, and tocopherols and risk of breast cancer. Am J Epidemiol. 161(2):153-60, 2005.
16. Sesso HD, Buring JE, Zhang SM, et al. Dietary and plasma lycopene and the risk of breast cancer. Cancer Epidemiol Biomarkers Prev. 14(5):1074-81, 2005.
17. Sato R, Helzlsouer KJ, Alberg AJ, et al. Prospective study of carotenoids, tocopherols, and retinoid concentrations and the risk of breast cancer. Cancer Epidemiol Biomarkers Prev. 11:451-457, 2002.
18. Toniolo P, Van Kappel AL, Akhmedkhanov A, et al. Serum carotenoids and breast cancer. Am J Epidemiol. 153(12):1142-7, 2001.
19. Hulten K, Van Kappel AL, Winkvist A, et al. Carotenoids, alpha-tocopherols, and retinol in plasma and breast cancer risk in northern Sweden. Cancer Causes Control. 12: 529-537, 2001.
20. Dorgan JF, Sowell A, Swanson CA, et al. Relationships of serum carotenoids, retinol, α-tocopherol, and selenium with breast cancer risk: results from a prospective study in Columbia, Missouri. Cancer Causes Control. 9: 89-97, 1998.
Updated 09/12/09
