Nuts and Olestra for Persistent Organic Pollutant Reduction (NO-POPs) Trial
Condition: Persistent Organic Pollutants; Endocrine Disrupting Chemicals; Endocrine Disruptor Effects
Study type: Interventional

Summary: 
      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.
    

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).
    

Intervention name(s): Whole Nuts; Olestra: Fat Free Pringles; Vegetable Oil: Original Pringles
Intervention type(s): Other; Other; Other
Intervention description(s): 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.; 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.; 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.
Intervention MeSH terms: Sucrose polyester
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment