Effects of Milk Chocolate Versus Dark Chocolate on Biomarkers of Inflammation and Bone Metabolism During Weight Loss

Recipient Organization
VIRGINIA POLYTECHNIC INSTITUTE
(N/A)
BLACKSBURG,VA 24061

Performing Department
HUMAN NUTRITION & FOODS

Non Technical Summary
Weight loss often results in loss of bone mineral. This project evaluates changes in biomarkers of inflammation and bone metabolism as well as bone mineral in overweight premenopausal women who lose weight.

Animal Health Component

100%

Research Effort Categories

Basic

(N/A)

Applied

100%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
702	6010	1010	100%

Knowledge Area
702 - Requirements and Function of Nutrients and Other Food Components;

Subject Of Investigation
6010 - Individuals;

Field Of Science
1010 - Nutrition and metabolism;

Keywords

bone mineral

bone turnover

inflammation

low fat, high carbohydrate

Goals / Objectives
The primary aim of this study is to evaluate the changes in biomarkers of inflammation and bone metabolism as well as bone mineral density (BMD) in overweight premenopausal women who follow a low-fat, high-carbohydrate diet with a daily milk chocolate snack compared to a low-fat, high-carbohydrate diet with a daily dark chocolate snack designed to induced weight loss. To achieve Specific Aim #1, four objectives will be met. During an 18-week diet intervention period: (1) changes in biochemical markers of inflammation, including tumor necrosis factor-alpha, interleukin-1, interleukin-6, and C-reactive protein will be measured; (2) changes in biomarkers of bone turnover, including bone formation (serum osteocalcin) and bone resorption (serum N-telopeptide) will be measured; (3) changes in biomarkers of mineral metabolism (serum and urinary calcium and phosphorus) will be measured; (4) BMD of the total body, lumbar spine, total proximal femur (hip), and total forearm will be measured. The secondary aim of this study is to compare changes in blood lipid profiles among overweight premenopausal women who follow a low-fat, high-carbohydrate diet with a daily milk chocolate snack compared to a low-fat, high-carbohydrate diet with a daily dark chocolate snack designed to induce weight loss. To achieve Specific Aim #2, one objective will be met. During an 18-week diet intervention period: (5)changes in serum total cholesterol, high-density lipoprotein, low-density lipoprotein, and triglycerides will be measured.

Project Methods
Thirty premenopausal women, aged 30 to 45 years, will participate in this 18-week study. A randomized, controlled trial of weight loss will be conducted. The base diet will include a low-fat, high-carbohydrate approach. Women will follow a weight loss diet that incorporates milk chocolate or dark chocolate into the food intake plan or will follow a weight loss diet that does not include chocolate (control diet). Women will engage in weekly nutrition education and motivation sessions. They will complete 4-day dietary intake records at intervals throughout the study. Four testing sessions will take place: baseline and weeks 6, 12, and 18. During each testing session, women will have their body weights and waist and hip circumferences measured; will provide blood and urine samples; and will have body composition, including bone mineral, measured. From blood samples, serum tumor necrosis factor-alpha, interleukin-1, interleukin-6, C-reactive protein, N-telopeptide, and osteocalcin will be measured. In addition, serum calcium and phosphorus will be determined as will serum total cholesterol, high-density lipoprotein, low-density lipoprotein, and triglycerides. Urinary calcium and phosphorus will be determined. Dual-energy X-ray absorptiometry will be used to measure bone mineral density of the total body, lumbar spine, hip, and forearm in women as they lose weight. From the total body data, body lean mass and fat mass will be determined.

Progress 04/01/06 to 09/30/06

Outputs
During the period April 1, 2006 through September 30, 2006, subject recruitment, development of dietary guidelines and nutrition education sessions for diet treatment groups, and laboratory preparation activities were conducted. Seventy-one women contacted the Principal Investigator (PI) with interest in participation in the study. Twenty-four women completed and returned study screening forms. Of these women, three met the criteria for inclusion. A dietetic intern, under the guidance of the PI, prepared six sets of menus for participants in the two diet treatment groups. In addition, five lesson plans for nutrition education and food intake monitoring were prepared for use with dietary education of study participants. Basic laboratory supplies were secured, and the laboratory was prepared for baseline testing of study subjects.

Impacts
Relevance: Weight loss may contribute to the risk of developing osteoporosis, a disease that impacts over 10 million individuals in the United States and costs more than $15 billion to treat. The Virginia Tech College of Agriculture and Life Sciences has identified food, nutrition, and health as a primary area of discovery. Response: Recruitment and preparatory steps for a weight loss study were initiated to investigate the bone responses in overweight women who follow a low-fat, high-carbohydrate diet with a daily milk chocolate snack compared to a low-fat, high-carbohydrate diet with a daily dark chocolate snack. Results: Subject recruitment was initiated. Dietary treatment plans and nutrition education sessions specific to dietary interventions were developed. Laboratory preparations were completed.

Publications

No publications reported this period