Dietary Phytochemical Index and the Risk of Breast Cancer: A Case Control Study in a Population of Iranian Women

Abstract

In this study we assessed the dietary phytochemical index in relation to the risk of breast cancer in women. This case-control study was conducted on 100 incident breast cancer cases and 175 healthy controls. Data regarding socio-demographic factors, medical history, medications, and anthropometric measurements were collected. Dietary data were obtained using a validated food frequency questionnaire and a energy-adjusted dietary phytochemical index (PI) was calculated. The odds ratios of breast cancer were assessed across energyadjusted PI quartile categories. The mean age of participants was 46.2±8.9 and 45.9±9.4 years in cases and controls, respectively. The mean PI across quartile categories was 13.9±2.6, 21.1±1.8, 26.7±2.1, 41.6±10.2 in the first, second, third and fourth quartiles, respectively. After adjustment for all potential confounders, the risk of breast cancer in the forth quartile of dietary PI was significantly decreased (OR=0.08, 95%CI=0.01-0.84). Higher intake of phytochemical-rich foods is associated with lower risk of breast cancer.

A Review of the Science of Colorful, Plant-Based Food and Practical Strategies for “Eating the Rainbow”

“…PI has been shown to be inversely associated with body mass index, waist circumference, waist-to-hip ratio, and plasma oxidative stress [31]. A higher dietary PI was shown to have favorable effects on prevention of weight gain and reduction of body adiposity in adults [32], along with improved lipids [33,34], and lowered risk of hypertension [35] and breast cancer [36].…”

Dietary phytochemical index and overweight/obesity in children: a cross-sectional study

“…Higher DPI was also accompanied by a better diet quality characterized by a higher intake of dietary fiber, vitamin C and potassium in the study population. Previous studies have reported an inverse link between dietary DPI and risk of chronic diseases such as insulin resistance [20], prediabetes [21], depressive symptoms, anxiety, and psychological distress [22], breast cancer [23], hypertension [24], hypertriglyceridemia [25]. To date, a limited number of studies have assessed the association between dietary DPI and obesity; however, all have been conducted in the adult population.…”

Increased fruit and vegetable intake among older adults participating in Kentucky’s congregate meal site program

“…However, the results of this study demonstrated that, with participants consuming less than 100% of meal components, the average meal PI score based on consumption was 26.9. Literature has shown that greater PI scores, particularly those between 29.8 and 41.6, have favorable effects on blood triglyceride levels, blood cholesterol levels, breast cancer risk, and weight loss (Bahadoran et al, 2013; Golzarand et al, 2014). Considering that participants from our study consumed a mean PI score of 26.9 from only one of the day's meals, there is the potential of reaching the ideal PI range if participants consumed similar nutritious meals throughout the day.…”

“…The PI score is a ratio calculation derived from the energy of high phytochemical-rich food in kilocalories (kcal) to the overall daily energy intake (kcal). Several studies have found PI scores ranging from 28.6 to 48.1 to be associated with positive health benefits such as weight loss, reduced risk of breast cancer, and improvement in triglyceride levels (Bahadoran, Karimi, Houshiar-rad, Mirzayi, & Rashidkhani, 2013; Golzarand, Mirmiran, Bahadoran, Alamdari, & Azizi, 2014; Vincent et al, 2010). …”