Date of Award

Fall 11-17-2018

Document Type


Degree Name

Master of Science (MS)


Human Ecology

First Advisor

Mary Fontenot


This study evaluated the role of phytonutrient intake on body composition. Both the quantity and types of phytonutrients in diets were analyzed. Fifty (50) subjects (15 males; 35 females) from Thibodaux, Louisiana, were randomly selected to participate. All participants completed three 24-hour food recalls to gather intake data (food and calorie intake). The phytonutrient index (PI) was an established formula used to calculate the percentage (%) of the diet comprised of phytonutrient rich foods. Three different body assessment tools were used to determine body adiposity (body mass index [BMI], waist circumference, and fat percentage).

Participants who met healthy standards for BMI, waist circumference, and fat percentage all averaged much higher PI scores compared to those who were classified as obese/overweight. The data showed a strong inverse relationship between PI and BMI (r = -0.753, p = 0.00), waist circumference (r = -0.730, p = 0.00), and body fat percentage (r = -0.701, p = 0.00).

Each participant was administered a food frequency questionnaire to assess the intakes of the specific phytonutrients based on color identity (green colored plants are chlorophyll-rich; reddish-purple foods are anthocyanin-rich; and orange-yellowish foods are carotenoid rich). Individuals with higher weekly intakes of chlorophyll, carotenoid, and anthocyanin rich foods had better body composition in comparison to those who consumed less (p<0.05).

These results suggest a strong correlation between higher phytonutrient intake and improved body composition, regardless of the type of phytonutrients consumed. Overall diet quality seems to make the most difference, but the phytonutrients in fruits/vegetables are thought to be a key reason for those benefits.