Nuts and Olestra for Persistent Organic Pollutant Reduction (NO-POPs) Trial (NO-POPs)

July 2, 2019 updated by: Jose R Suarez, University of California, San Diego

Nuts and Olestra for Persistent Organic Pollutant Reduction (NO-POPs) Trial: A Pilot Investigation

Persistent organic pollutants (POPs) are mostly fat-soluble halogenated chemicals with very long half-lives. POPs are endocrine disruptors, associated with increased risk for diabetes, alterations in thyroid function, and cardiovascular disease in humans. POPs concentrations increase with age because of their persistence, bioaccumulation and poor excretion. The almost ubiquitous presence of endocrine disrupting POPs in US adults is a substantial public health concern, particularly because there is no established treatment to reduce body concentrations of POPs. Most POPs are excreted in bile due to their lipophilic nature. However, a substantial amount is reabsorbed in the small intestine and returns to the blood stream (entero-hepatic circulation). The objective of this pilot study is to conduct a 6-month randomized controlled trial of Nuts and Olestra to enhance the excretion of POPs among 45 healthy adults aged 45 to 70 years with BMIs between 18-30 kg/m2. This study has 3 treatment arms: A) Whole nuts with high fat content (almonds and walnuts; 110g total/day, n=15), B) Olestra: Fat Free PringlesTM potato chips (≈29 crisps, 18g of Olestra/day; n=15), C) Vegetable oil: Original PringlesTM potato chips (≈29 crisps, 17.4g of oil/day; n=15). The investigators aim to measure change in concentrations of 24 POPs in feces after 4 days of treatment and in blood at 6 months.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Persistent organic pollutants (POPs) are mostly fat-soluble halogenated chemicals with very long half-lives. POPs are endocrine disruptors, and have been associated with increased risk for diabetes, alterations in thyroid function, hypertension, dyslipidemia and neurobehavioral alterations in studies of children, and adults including the elderly. Some of the most prevalent POPs include organochlorine pesticides, polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs).

Most POPs are excreted in bile due to their lipophilic nature. However, a substantial amount is reabsorbed in the small intestine and returns to the blood stream (entero-hepatic circulation). Two small clinical trials found that bile acid sequestrants (cholestyramine, cholestimide) enhanced the fecal excretion of organochlorines after 2-3 days of treatment and significantly lowered their blood concentrations at 6 months. One pilot trial reported decreases in blood PCB concentrations in adults after a 1 year treatment with fat-free potato crisps made with olestra, a non-absorbable synthetic fat, versus standard potato crisps. POPs were thought to bind to olestra and be excreted in the feces. Replication of this finding is needed. Nuts, could yield similar effects. Nuts are foods with high-fat content which are incompletely absorbed in the intestine (21-24% of calorie not absorbed).

As people age, the body burdens of POPs increase. The almost ubiquitous presence of endocrine disrupting POPs in US adults is a substantial public health concern, particularly because there is no established treatment to reduce body concentrations of POPs. There is potential for dietary interventions to have an important role in the reduction of POPs at a population level due to their and low cost and wide use.

The investigators aim to measure 24 POPs (9 OC pesticides, 10 PCBs, 5 PBDEs) in blood (all participants) and in stool samples (only in a subset of 10 participants per treatment arm) before and during the treatment period. The specific aims of this pilot study are to:

  1. Assess the effectiveness of recruitment strategies, acceptance and compliance of the treatment arms, and establishing the feasibility of conducting a larger trial.
  2. Conduct preliminary testing of the hypotheses: Consumption of olestra (fat free Pringles): A) increases the fecal content (excretion) of POPs, and B) decreases blood levels of POPs, compared to the control arm (standard crisps).
  3. Conduct preliminary testing of the hypotheses: Consumption of nuts: A) increases the fecal content (excretion) of POPs, and B) decreases blood levels of POPs, compared to the control arm (standard crisps).

Study Type

Interventional

Enrollment (Actual)

45

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • California
      • La Jolla, California, United States, 92093
        • UCSD Moores Cancer Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

45 years to 70 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Reside in the San Diego area
  • BMI ≥18.0 kg/m2 and ≤30 kg/m2
  • Non-smoker
  • Willing and able to participate in clinic visits, bi-monthly supply pick-up, telephone and Internet communications at specified intervals
  • Able to provide data through questionnaires and by telephone
  • Willing to maintain contact with the investigators for 6 months
  • Willing to allow blood collections
  • Willing to provide stool samples
  • No known allergy to tree nuts
  • No digestive issues with olestra, chips, or nuts

Exclusion Criteria:

  • Nut allergies
  • Smoker
  • Diabetes, kidney disease or liver disease
  • Concurrent acute or chronic gastro-intestinal conditions (e.g. inflammatory bowel disease, irritable bowel syndrome, concurrent diarrhea from any cause)
  • Familial hypercholesterolemia
  • Clotting problems or use of Coumadin,
  • Inability to participate in physical activity because of severe disability
  • History or presence of a co-morbid diseases for which diet modification may be contraindicated
  • Self-reported pregnancy or breastfeeding or planning a pregnancy within the next year
  • Currently actively involved in another diet intervention study or a weight loss program
  • A history or presence of a significant psychiatric disorder or any other condition that, in the investigator's judgement, would interfere with participation in the trial

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Whole nuts
Participants will be advised on maintaining an iso-caloric diet by a Registered Dietitian. During the 6-month intervention, study subjects will consume a combination of whole almonds and walnut pieces, a total of 110 g per day. Participants will pick up supplies and be weighed 1-2 times per month for six months. Participants will also maintain a diary of their intake using an automated system. Walnuts and almonds will be provided to participants for the duration of the study.
Other: Whole Nuts
Participants will be advised on maintaining an iso-caloric diet. Aside consuming nuts, the remaining composition of the prescribed diet will be based on individual preferences. During the 6-month intervention, study subjects will meet with study staff every 2-3 weeks to weigh in, pick up food supplies and complete a questionnaire on compliance. All participants will have contact with the project coordinator/study dietitian a minimum of every 1-2 weeks either in-person, telephone, email and text message contacts for support, behavioral guidance and strategies. Both walnuts and almonds will be provided to participants in the whole nut study arm.
Experimental: Olestra: Fat Free Pringles
Participants will be advised on maintaining an iso-caloric diet by a Registered Dietitian. During the 6-month intervention, study subjects will consume 29 potato crisps per day, which is approximately 18 g olestra/day. Participants will pick up supplies and be weighed 1-2 times per month for six months. Participants will also maintain a diary of their intake using an automated system. Fat free Pringles will be provided to participants for the duration of the study.
Other: Olestra: Fat Free Pringles
Participants will be advised on maintaining an iso-caloric diet. Aside consuming fat free potato crisps, the remaining composition of the prescribed diet will be based on individual preferences. During the 6-month intervention, study subjects will meet with study staff every 2-3 weeks to weigh in, pick up food supplies and complete a questionnaire on compliance. All participants will have contact with the project coordinator/study dietitian a minimum of every 1-2 weeks either in-person, telephone, email and text message contacts for support, behavioral guidance and strategies. Fat Free Pringles will be provided to participants in the olestra study arm.
Placebo Comparator: Vegetable Oil: Original Pringles
Participants will be advised on maintaining an iso-caloric diet by a Registered Dietitian. During the 6-month intervention, study subjects will consume 29 potato crisps per day, which is approximately 17.4 g oil/day. Participants will pick up supplies and be weighed 1-2 times per month for six months. Participants will also maintain a diary of their intake using an automated system. Original Pringles will be provided to participants for the duration of the study.
Other: Vegetable Oil: Original Pringles
Participants will be advised on maintaining an iso-caloric diet. Aside consuming potato crisps, the remaining composition of the prescribed diet will be based on individual preferences. During the 6-month intervention, study subjects will meet with study staff every 2-3 weeks to weigh in, pick up food supplies and complete a questionnaire on compliance. All participants will have contact with the project coordinator/study dietitian a minimum of every 1-2 weeks either in-person, telephone, email and text message contacts for support, behavioral guidance and strategies. Original Pringles will be provided to participants in the vegetable oil study arm.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Change in blood levels of persistent organic pollutants (POPS) in response to being assigned an olestra -enriched diet (fat-free Pringles) compared to a diet enriched with vegetable oil (original Pringles) over a 6-month period
Time Frame: 6 months
6 months
Change in fecal excretion of persistent organic pollutants (POPS) in response to being assigned an olestra -enriched diet (fat-free Pringles) compared to a diet enriched with vegetable oil (original Pringles) over a 6-month period
Time Frame: 6 months
6 months

Secondary Outcome Measures

Outcome Measure
Time Frame
Change in blood levels of persistent organic pollutants (POPS) in response to being assigned a nut-enriched diet compared to a diet enriched with vegetable oil (original Pringles) over a 6-month period
Time Frame: 6 months
6 months
Change in fecal excretion of persistent organic pollutants (POPS) in response to being assigned a nut-enriched diet compared to a diet enriched with vegetable oil (original Pringles) over a 6-month period
Time Frame: 6 months
6 months

Other Outcome Measures

Outcome Measure
Time Frame
Change in blood lipids in response to being assigned an olestra -enriched diet (fat-free Pringles), a vegetable oil-enriched diet (original Pringles) or a nut-enriched diet over a 6-month period, as an exploratory aim.
Time Frame: 6 months
6 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of California, San Diego

Collaborators

San Diego State University

Investigators

  • Principal Investigator: Jose R Suarez, MPH, MD, PhD, University of California, San Diego

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

March 1, 2016

Primary Completion (Actual)

February 1, 2017

Study Completion (Actual)

April 1, 2019

Study Registration Dates

First Submitted

January 28, 2016

First Submitted That Met QC Criteria

February 2, 2016

First Posted (Estimate)

February 5, 2016

Study Record Updates

Last Update Posted (Actual)

July 5, 2019

Last Update Submitted That Met QC Criteria

July 2, 2019

Last Verified

July 1, 2019

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 160096

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Endocrine Disrupting Chemicals

Clinical Trials on Whole Nuts

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Norway

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe