Diet and Systemic Inflammation — DASI  

Obesity Clinical Trial

Official title: Diet and Systemic Inflammation

Status Completed

Clinical Trial Summary

People with chronic low-grade inflammation have a higher risk for certain diseases such as cardiovascular disease or type 2 diabetes. While it is known that obese people are more likely to show signs of low-grade inflammation than lean individuals, it is unclear what causes this inflammation. In the proposed study, the investigators will examine whether the sugar fructose, when consumed in a sweetened beverage, triggers low-grade inflammation in healthy men and women compared with other caloric sweeteners.

Clinical Trial Description

The objective of this proposal is to investigate whether fructose-sweetened beverages trigger low-grade systemic inflammation in healthy men and women. Low-grade systemic inflammation, specifically elevated plasma concentrations of C-reactive protein (CRP), is a risk factor for cardiovascular disease (CVD). While it is known that obesity is associated with inflammation, the causes of low-grade inflammation in humans are not well understood. In a pilot study, the consumption of large amounts of fructose-, but not glucose- or aspartame-sweetened beverages potently induced low-grade inflammation in healthy, lean, young men and women in as little as 8 days. The investigators propose to extend these findings by (a) enrolling a greater number of subjects, (b) enrolling obese as well as non-obese subjects, and (c) including a beverage that is sweetened with high fructose corn syrup (HFCS). HFCS is one of the primary sugars consumed in the United States, and a major source of dietary fructose. Our primary specific aim is to assess whether the consumption of fructose- or HFCS-sweetened beverages promotes systemic low-grade inflammation, as measured by plasma concentrations of CRP and IL-6. The investigators hypothesize that plasma CRP and IL-6 concentrations will be elevated after consumption of fructose-containing beverages (fructose and HFCS) when compared to a glucose-sweetened beverage. Our secondary specific aim is to assess whether the consumption of fructose- or HFCS-sweetened beverages lowers plasma adiponectin concentrations. Specifically, the investigators hypothesize that total and high molecular weight (HMW)-adiponectin concentrations in fasting plasma will be lower after subjects have consumed the fructose- or HFCS-sweetened beverages, compared to a glucose-sweetened beverage.

The investigators will recruit 12 overweight/obese (BMI between 25.0 and 40 kg/m2) and 12 normal weight (BMI between 20 and 24.9 kg/m2) men and women who are free of chronic inflammatory or metabolic disease. In a double-blind, randomized cross-over design, each subject will complete three 8-day standardized dietary periods that will differ only in the type of sweetened beverage administered. Specifically, subjects will be asked to drink four servings of a beverage each day that is sweetened with glucose, fructose, or HFCS (55% fructose, 45% glucose). All solid food will be provided for each of the three 8-day diet periods, and will be consumed ad libitum. Following each dietary period, the investigators will collect fasting blood to measure markers of systemic inflammation and plasma concentrations of total and HMW-adiponectin. We will also assess changes in adipose tissue inflammation and intestinal permeability as potential mechanisms by which fructose-sweetened beverages may trigger systemic inflammation. This study has the potential to identify a dietary trigger of low-grade inflammation, a likely contributor to CVD and metabolic diseases. The public health impact of this project might be considerable given that the consumption of fructose in the population is pervasive, and is modifiable on an individual as well as a population level. ;

Study Design

Allocation: Randomized, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Cardiovascular Disease
• Cardiovascular Diseases
• Diabetes Mellitus
• Diabetes Mellitus, Type 2
• Inflammation
• Intestinal Permeability
• Low-grade Chronic Inflammation
• Obesity
• Type 2 Diabetes Mellitus

• NCT number: NCT01424306
• Study type: Interventional
• Source: Fred Hutchinson Cancer Research Center
• Status: Completed
• Phase: N/A
• Start date: October 2011
• Completion date: April 2014