Use of Stable Carbon And Nitrogen Isotopes to Improve Dietary Assessment for Cardiovascular Disease

NCT ID: NCT04933656

Last Updated: 2026-01-26

Basic Information

• Recruitment Status: WITHDRAWN
• Clinical Phase: NA
• Study Classification: INTERVENTIONAL
• Study Start Date: 2021-08-31
• Study Completion Date: 2022-02-28

Brief Summary

In this research study, the investigators will use a novel approach to measure what people eat. The goal is to find out whether stable isotopes that can be measured in blood, hair, and fingernails are better at measuring what people eat than the surveys that are currently used. To meet the goal, the investigators will do three things. First, the investigators will feed study participants known amounts of foods and nutrients. Second, after study participants have eaten the food, the investigators will measure stable isotopes in samples of study participants' blood, hair, and fingernails. Third, the investigators will determine how well these samples reflect what was eaten. The investigators will also give surveys to study participants to determine how well the surveys reflect what was eaten. This will allow the investigators to do a relative comparison of the measurements from isotopes and surveys.

Detailed Description

This is a controlled feeding study in which the relative validity of stable carbon and nitrogen isotope ratio analysis as a biomarker of dietary intake is compared to controlled feedings and multiple 24-hour recalls. Participants will be randomly assigned to a sequence of diets to be fed on four occasions. Participants will undergo 24 hours of controlled feeding on four non-consecutive days over a month-long period. On the day after feeding, participants will complete 24-hour dietary recalls, and provide blood, hair, and fingernail samples for isotope ratio analyses. The investigators will use a crossover design and the diets will be either high or low in C4 plants (i.e., corn and cane products). A 24-hour urine collection will be done at home during each 24-hour feeding period. Participants will have height and weight measured at the screening visit. Weight will also be measured at each study visit. Additionally, data will be collected via questionnaires administered at each study visit.

Conditions

Healthy Adults

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: HEALTH_SERVICES_RESEARCH
• Blinding Strategy: DOUBLE

Study Groups

50g added sugar

Crossover design and each participant receives all 4 experimental arms/doses in random order

Group Type: EXPERIMENTAL

one 24 hr cycle of meals at a 2000 kcal level

Intervention Type: DIETARY_SUPPLEMENT

50g added sugar

90g added sugar

Crossover design and each participant receives all 4 experimental arms/doses in random order

Group Type: EXPERIMENTAL

one 24 hr cycle of meals at a 2000 kcal level + one serving sugar sweetened beverage

Intervention Type: DIETARY_SUPPLEMENT

90 grams added sugar

130g added sugar

Crossover design and each participant receives all 4 experimental arms/doses in random order

Group Type: EXPERIMENTAL

one 24 hr cycle of meals at a 2000 kcal level + two servings sugar sweetened beverage

Intervention Type: DIETARY_SUPPLEMENT

130 grams added sugar

170g added sugar

Crossover design and each participant receives all 4 experimental arms/doses in random order

Group Type: EXPERIMENTAL

one 24 hr cycle of meals at a 2000 kcal level + three serving sugar sweetened beverage

Intervention Type: DIETARY_SUPPLEMENT

170 grams added sugar

Interventions

one 24 hr cycle of meals at a 2000 kcal level

50g added sugar

Intervention Type: DIETARY_SUPPLEMENT

one 24 hr cycle of meals at a 2000 kcal level + one serving sugar sweetened beverage

90 grams added sugar

Intervention Type: DIETARY_SUPPLEMENT

one 24 hr cycle of meals at a 2000 kcal level + two servings sugar sweetened beverage

130 grams added sugar

Intervention Type: DIETARY_SUPPLEMENT

one 24 hr cycle of meals at a 2000 kcal level + three serving sugar sweetened beverage

170 grams added sugar

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

Inclusion Criteria

• men and women;
• aged 21 and 74 years;
• no history of chronic disease and in general good health;
• able to provide primary study outcome; and
• willing to tolerate study diets designed for controlled feeding.

Exclusion Criteria

• recent dietary changes, restrictions, allergies or preferences;
• health conditions that require management beyond the scope of the study (e.g. heart failure, kidney disease, liver disease, gastrointestinal disorder);
• history of drug or alcohol abuse;
• plans to leave the San Diego area before study completion; and
• lack of suitability per investigators' discretion.

• Minimum Eligible Age: 21 Years
• Maximum Eligible Age: 74 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of California, San Diego

OTHER

Sponsor Role: lead

Responsible Party

Cheryl A. Anderson, MPH, PhD

Professor, Interim Chair

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Cheryl A. Anderson, PhD

Role: PRINCIPAL_INVESTIGATOR

University of California, San Diego

Locations

University of California, San Diego

San Diego, California, United States

Countries

United States

Other Identifiers

16IRG27770080

Identifier Type: -

Identifier Source: org_study_id