Sex Hormones in Women With Elevated Breast Cancer Risk Undergoing Weight Loss

Abstract

Sedentary lifestyles and obesity are known risk factors for breast cancer. Elevated estrogen levels correlate with obesity and, independently, with increased breast cancer risk. Lifestyle interventions that reduce obesity may mitigate this risk, potentially via estrogen pathways. In a 6-month lifestyle intervention, overweight/obese women with high breast cancer risk were randomized to control (n = 7) or intervention (n = 6) and analyzed for sex hormone levels. Serum and urine hormones were evaluated by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and sex hormone binding globulin (SHBG) by enzyme-linked immunosorbent assay (ELISA). Serum estrone (E1) and estradiol (E2) were reduced by 12.1% and 50.8%, respectively, at 9 months in the intervention group, which differed from controls (p = .043 and .020). This contrasted with a 73.3% increase in urine E1 at 6 months in the intervention group (p = .035). These results suggest that a lifestyle intervention led to a favorable estrogen profile in relation to breast cancer risk.

Trial registration: ClinicalTrials.gov NCT01874184.

Keywords: breast neoplasms; estrogens; mindfulness; public health; weight loss.

Conflict of interest statement

Declaration of Conflicting Interests

The Authors declare that there is no conflict of interest.

Figures

Figure 1.. Theoretical framework for the Biobehavioral Study of the DEEM intervention based on Social Cognitive Theory (Bandura, 2011).

Note. DEEM = Diet, Exercise, Emotional, and Mindfulness.

Figure 2.

(a) Consolidate Standards of Reporting Trials (CONSORT) Flow Diagram and (b) DEEM intervention study design (Han et al., 2018).

Figure 3.. Changes in body composition and serum and urine estrogens in the intervention and control groups.

E1 = estrone; E2 = estradiol; * indicates statistically significant differences in changes of each outcome variable between the intervention and control groups (p < 0.05).

Figure 4.. Relationship between the change in estrone excretion and adiposity loss at 6 months.

A statistically significant negative correlation (r = −0.592, N = 13, p = 0.032) was found between the change in urinary estrone excretion and change in adiposity at 6 months.