Do Flavonoid Intakes of Postmenopausal Women With Breast Cancer Vary on Very Low Fat Diets?

Abstract

In the Women's Intervention Nutrition Study (WINS), a very low-fat eating pattern decreased breast cancer recurrence. We assessed whether the women's flavonoid intakes varied on the very low fat diet. A total of 550 randomly selected WINS participants who had been treated with conventional therapy (surgery, chemotherapy, and/or radiation) for primary breast cancer were randomized to either a very low fat diet (15% of calories from fat, N = 218) or their usual diets (30% calories from fat, N = 332). We compared their intakes of total flavonoids and 6 flavonoid classes (isoflavones, flavones, flavanones, flavonols, flavan-3-ols, and anthocyanins) for these 2 groups using the U.S. Department of Agriculture food flavonoid database and a flavonoid dietary supplement database on three 24-h dietary recalls at baseline and 12 mo after randomization. At baseline, neither mean fat intakes (31.7% +/- 6.8 SD of calories, n = 332 in the usual diet group and 31.6% +/- 6.8 SD of calories, n = 218 in the very low fat diet group; P = NS) nor flavonoid intakes (218 +/- 283 SD mg/day, n = 332 in the usual diet group and 236 +/- 393 SD mg/day, n = 218 in the very low fat diet group; P = NS) differed. Over half of the women's flavonoid intakes were from the flavan-3-ols. After 12 months of intervention, with 39 participants lost to follow-up, dietary fat intakes were 30.7 +/- 8.4 SD calories (n = 316) among those on their usual diets but were significantly lower among those on the very low fat diet intervention: 21.4 +/- 8.3 SD calories (n = 195), P = <0.05. However, flavonoid intakes remained similar in both groups (201 +/- 252 SD mg/day, n = 316 in the usual diet group vs. 235 +/- 425 SD mg/day, n = 195 in the very low fat group; P = NS). In this random sample of WINS participants, neither total flavonoid intakes nor intakes of subclasses of flavonoids differed between those who had dramatically decreased their fat intakes and those who had not. Flavonoid intakes are therefore unlikely to account for WINS results on differences between the groups in cancer recurrence.

Flavonoid intake and cardiovascular disease mortality in a prospective cohort of US adults

“…For example, dark chocolate and herbs such as peppermint and parsley were not included on the current questionnaire, but consumption is assumed to have been relatively low in the United States at the time of this survey. We believe that the majority of important flavonoid sources in the US diet were captured because total estimates (mean: 268 mg/d; median: 202 mg/d) were intermediate between estimates derived from the 2003 USDA database [for 6 (54,55) or 7 (14) flavonoid classes] and from the 2007 USDA database (in health professionals) (15). Due to multiple associations examined, some of our significant findings would be expected by chance.…”

The role of diet and physical activity in breast, colorectal, and prostate cancer survivorship: a review of the literature

“…The early contradictory findings from the large-scale WINS and WHEL trials in the 1990s and their subsequent secondary analysis studies (Khaodhiar et al , 2003; Chlebowski et al , 2006, 2008; Pierce et al , 2007; Thomson et al , 2007; Dwyer et al , 2008; Gold et al , 2009; Caan et al , 2011) established a strong focus on the role of fat reduction and significant changes in diet (including fat reduction) as important factors for breast cancer prognosis. This was especially so for post-menopausal breast cancer survivors.…”

“…In evaluating the impact of diet and physical activity on cancer progression and survival, evidence from prospective observational studies suggests that physical activity and diet may be associated with improved cancer progression and recurrence (Khaodhiar et al , 2003; Holmes et al , 2005; Chlebowski et al , 2006, 2008; Pierce et al , 2007; Thomson et al , 2007; Dwyer et al , 2008; Holick et al , 2008; Irwin et al , 2008, 2009; Gold et al , 2009; Goodwin et al , 2009; Belle et al , 2011; Caan et al , 2011; Chen et al , 2011). In particular, the evidence suggests that a low-fat, high-fibre diet might be protective against breast, colorectal and prostate cancer recurrence and progression.…”

Dietary flavonoid intake in older adults: how many days of dietary assessment are required and what is the impact of seasonality?

“…For example, a Food Frequency Questionnaire (FFQ) and a 24 h diet recall would produce fundamentally different estimates of flavonoid intake, given the inherent differences in the recall and reporting periods of each tool. When assessing flavonoid intake, the majority of studies have applied a FFQ [ 26 – 28 ] to capture habitual intake, while fewer studies have utilised either single [ 29 , 30 ] or multiple 24 h recalls [ 31 ], diet history methods [ 32 ] and food records [ 33 ]. The use of FFQs to determine flavonoid intake has limitations, as often a retrospective secondary analysis of flavonoid intake is conducted [ 34 ] from a FFQ tool that has not specifically been designed to assess flavonoid intake.…”