Recent diet and breast cancer risk: The California Teachers Study (USA)

Northern California Cancer Center, Union City 94587, USA.
Cancer Causes and Control (Impact Factor: 2.74). 07/2002; 13(5):407-15. DOI: 10.1023/A:1015786030864
Source: PubMed


The impact, if any, on breast cancer risk of modifying adult dietary intake is an area of much interest. We take the opportunity to address the relationship between recent adult diet and breast cancer risk during the first two years of follow-up of the large California Teachers Study cohort.
Of the 111.526 at-risk cohort members who resided in California and completed a baseline dietary assessment, 711 were diagnosed with invasive breast cancer after joining the cohort and before January 1998. Average daily nutrient intake was computed based on a food-frequency questionnaire assessing usual dietary intake and portion size during the year prior to joining the cohort. Incident breast cancers were identified through the California Cancer Registry and follow-up for death and confirmation of continued California residence utilized a variety of data sources. Cox proportional hazards models were used to calculate relative hazards.
The following components of recent dietary intake were not associated with breast cancer risk: energy, fat, fiber, antioxidant vitamins, and phytoestrogens. Only recent average alcohol consumption of 20 or more grams per day (approximately two or more glasses of wine) was associated with increased risk (RR= 1.5, 95% CI: 1.2-2.0 compared to non-drinkers; P(trend) = 0.01 across quintiles).
With the exception of alcohol consumption, this study provides no evidence that recent macro- or micronutrient composition of adult diet is likely to have a direct effect on breast cancer risk. Some reduction of alcohol consumption among those consuming more than one drink per day may be beneficial.

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Available from: Pamela L Horn-Ross, Oct 05, 2015
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    • "Dietary isoflavone level has been investigated in epidemiological studies since 2001. So far, few studies have been conducted on the quantities of isoflavone intake in populations[22]-[25]. No research has been conducted in women with long-term consumption of such highly-processed soy supplements. "
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    01/2012; 26(1):44-52. DOI:10.1016/S1674-8301(12)60006-2
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    • "Epidemiological studies have evaluated intake of total fiber in relation to overall breast cancer risk in a pooled analysis of 12 case–control studies conducted before 1986 (Howe et al., 1990), 12 case–control studies published recently (Van't Veer et al., 1990; Graham et al., 1991; Baghurst and Rohan, 1994; Yuan et al., 1995; Franceschi et al., 1996; Freudenheim et al., 1996; De Stefani et al., 1997a; Potischman et al., 1999; Ronco et al., 1999; Adzersen et al., 2003; Bonilla-Fernandez et al., 2003; Shaham et al., 2006) and 17 cohort studies (Graham et al., 1992; Willett et al., 1992; Rohan et al., 1993; Kushi et al., 1995; Jarvinen et al., 1997; Verhoeven et al., 1997; Horn-Ross et al., 2002; Terry et al., 2002; Cho et al., 2003; Holmes et al., 2004; Mattisson et al., 2004; Giles et al., 2006; Cade et al., 2007; Lajous et al., 2008; Suzuki et al., 2008; Park et al., 2009; Wen et al., 2009); however, the results are inconsistent. Recent studies have raised the hypothesis that the association of dietary factors with breast cancer may differ by hormone receptor status (Colditz et al., 2004; Fung et al., 2005; Zhang et al., 2005). "
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