Fruit and vegetable consumption and incident breast cancer: a systematic review and meta-analysis of prospective studies

Abstract

Background: We conducted a systematic review and meta-analysis of prospective studies to clarify the relation of fruit and vegetable consumption with incident breast cancer.

Methods: We searched systematically PubMed and EMBASE databases up to November 2020 to include prospective studies that reported the association of fruit and vegetable consumption with incident breast cancer. The pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated for the highest versus the lowest category of total fruit and vegetable, total fruit and total vegetable consumption, as well as fruit juice and subgroups of vegetables in relation to breast cancer incidence, using a random-effect model.

Results: Total fruit and vegetable consumption was associated with lower overall (RR = 0.91, 95% CI = 0.87-0.95) and postmenopausal breast cancer risk (RR = 0.88, 95% CI = 0.79-0.99). Total fruit consumption was associated with lower overall (RR = 0.93, 95% CI = 0.88-0.99) and postmenopausal breast cancer risk (RR = 0.93, 95% CI = 0.87-0.99). Total fruit and vegetable intake were associated with 11% and 26% lower risk of oestrogen- and progesterone-receptor-positive (ER+/PR+) and -negative (ER-/PR-) breast cancer, respectively. Total vegetable consumption was associated with 27% lower risk of ER-/PR- breast cancer. Fruit juice consumption was associated with increased overall breast cancer risk (RR = 1.04, 95% CI = 1.01-1.07). We did not find significant associations for subgroups of vegetable intake and breast cancer risk.

Conclusions: These findings suggest that high total fruit and vegetable consumption are associated with reduced risk of overall, postmenopausal, ER+/PR+ and ER-/PR- breast cancer.

Fig. 1. Flowchart of study selection.

Search, screening and selection process of prospective studies of fruit, vegetable and fruit juice intake and breast cancer incidence.

Fig. 2. Associations of total fruit and vegetable intake and risk of breast cancer.

a Overall, b Premenopausal and c Postmenopausal. Forest plot shows relative risks and 95% confidence intervals comparing highest category versus lowest category, using random-effect models. BWHS Black Women’s Health Study, EPIC European Prospective Investigation into Cancer and Nutrition, JPHC Japan Public Health Center-based Prospective Study, LWS Leisure World Study, NHEFS National Health Epidemiologic Follow-up Study, NHS Nurses’ Health Study, NHSII Nurses’ Health Study II, WLH Swedish Women’s Lifestyle and Health Study.

Fig. 3. Associations of total fruit intake and risk of breast cancer.

a Overall, b Premenopausal and c Postmenopausal. Forest plot shows relative risks and 95% confidence intervals comparing highest category versus lowest category, using random-effect models. BWHS Black Women’s Health Study, CNBSS Canadian National Breast Screening Study, EPIC European Prospective Investigation into Cancer and Nutrition, FRiCaM Risk Factors for Breast Cancer: Fattori di Rischio per il Carcinoma della Mammella, JPHC Japan Public Health Center-based Prospective Study, KNCC Korean National Cancer Center Cohort, LSS The Radiation Effects Research Foundation’s Life Span Study, LWS Leisure World Study, MWS Million Women Study, NHS Nurses’ Health Study, NHSII Nurses’ Health Study II, NIH-AARP National Institute of Health-AARP Diet and Health Study, NLCS The Netherlands Cohort Study, SCHS the Singapore Chinese Health Study, UKWCS UK Women’s Cohort Study, VITAL VITamins And Lifestyle Cohort.

Fig. 4. Associations of fruit juice intake and risk of overall breast cancer.

Forest plot shows relative risks and 95% confidence intervals comparing highest category versus lowest category, using random-effect models. EPIC European Prospective Investigation into Cancer and Nutrition, FOS Framingham Offspring Study, MWS Million Women Study, NHS Nurses’ Health Study, NHSII Nurses’ Health Study II, SU.VI.MAX SUpplémental en VItamines et Minéraux AntioXydants, UKWCS UK Women’s Cohort Study.

Fig. 5. Associations of total vegetable intake and risk of breast cancer.

a Overall, b Premenopausal and c Postmenopausal. Forest plot shows relative risks and 95% confidence intervals comparing highest category versus lowest category, using random-effect models. BWHS Black Women’s Health Study, CNBSS Canadian National Breast Screening Study, EPIC European Prospective Investigation into Cancer and Nutrition, FRiCaM Risk Factors for Breast Cancer: Fattori di Rischio per il Carcinoma della Mammella, JPHC Japan Public Health Center-based Prospective Study, KC Karunagappally Cohort, LWS Leisure World Study, MWS Million Women Study, NHS Nurses’ Health Study, NHSII Nurses’ Health Study II, NIH-AARP National Institute of Health-AARP Diet and Health Study, NLCS the Netherlands Cohort Study, SCHS the Singapore Chinese Health Study, UKWCS UK Women’s Cohort Study, VITAL VITamins And Lifestyle Cohort, WLH Swedish Women’s Lifestyle and Health Study.

Fig. 6. Associations of total fruit and vegetable, total fruit and total vegetable intake and risk of overall breast cancer.

a Total fruits and vegetables, b Total fruits and c Total vegetables. Forest plot shows relative risks and 95% confidence intervals of each 200 g per day intake of total fruits and vegetables, total fruits and total vegetables, using random-effect models. BWHS Black Women’s Health Study, CNBSS Canadian National Breast Screening Study, EPIC European Prospective Investigation into Cancer and Nutrition, FRiCaM Risk Factors for Breast Cancer, Fattori di Rischio per il Carcinoma della Mammella, JPHC Japan Public Health Center-based Prospective Study, LSS The Radiation Effects Research Foundation’s Life Span Study, MWS Million Women Study, NHS Nurses’ Health Study, NHSII Nurses’ Health Study II, NLCS The Netherlands Cohort Study, UKWCS UK Women’s Cohort Study, VITAL VITamins And Lifestyle Cohort, WLH Swedish Women’s Lifestyle and Health Study.

Fig. 7. Associations of total fruit and vegetable, total fruit and total vegetable intake and risk of breast cancer based on hormone-receptor status.

a1 Total fruits and vegetables and ER+/PR+, a2 Total fruits and ER+/PR+, a3 Total vegetables and ER+/PR+, b1 Total fruits and vegetables and ER−/PR−, b2 Total fruits and ER−/PR− and b3 Total vegetables and ER−/PR−. Forest plot shows relative risks and 95% CIs comparing highest category versus lowest category, using random-effect models. BWHS Black Women’s Health Study, EPIC European Prospective Investigation into Cancer and Nutrition, JPHC Japan Public Health Center-based Prospective Study, NHS Nurses’ Health Study, NHSII Nurses’ Health Study II.