Enhancing the Benefits of Blueberry Polyphenols With Protein

Enhancing the Benefits of Blueberry Polyphenols With Plant and Whey Proteins

The purpose of this randomized crossover trial is determine whether acute consumption of blueberries with different proteins from plants (hemp or pea) or dairy (whey) impact the absorption of blueberry phytochemicals, which could impact the health benefits of blueberries. A secondary purpose is to understand the role that the gut microbiome may play, as well as the impact on urine polyphenol metabolites and potential implications for cardiometabolic health. Researchers will compare four arms: 1) Blueberries; 2) Blueberries + whey protein; 3) Blueberries + pea protein; and 4) Blueberries + hemp protein.

Study Overview

• Status: Completed
• Conditions: Healthy Adults
• Intervention / Treatment: Dietary supplement: Blueberries; Dietary supplement: Blueberries and Whey Protein; Dietary supplement: Blueberries and Pea Protein; Dietary supplement: Blueberries and Hemp Protein

Detailed Description

Polyphenols are a structurally diverse class of secondary metabolites found in plants, with numerous documented benefits for human health including, but not limited to, anti-inflammatory, antioxidative and cardiovascular-protective effects. Dietary intake of polyphenols in the United States is low in comparison to other developed countries due to low intake of fruits and vegetables. Recent studies suggest fruit and vegetable intake should be increased by incorporating those foods into snacks and mixed meals as ingredients rather than standalone food items. Presently, berries comprise 10% of the total fruit intake and 7% of the total polyphenol intake of American adults. As a versatile food ingredient, berries can easily be added to foods like smoothies and yogurts as an ingredient to increase intake.

Low polyphenol intake is an issue exacerbated by poor bioavailability. Consumption does not necessarily mean that these beneficial compounds are delivered to body tissues, as evidenced by low levels of detection in blood and accumulation in the lower gastrointestinal tract after feeding. Bioavailability can be enhanced through the complexation of polyphenols with proteins, a phenomenon which occurs naturally in complex mixtures including both classes of nutrients. It has been shown that the complexation of polyphenols with proteins in cow's milk, known as a "matrix effect", enhances the polyphenol stability and uptake throughout digestion. The incorporation of berries into complex food mixtures may not only be an opportunity for improved health outcomes due to increased polyphenol intake, but also an effective strategy for ensuring that consumers receive the benefits of the nutrients they consume.

It is unknown whether the beneficial matrix effects observed when polyphenols interact with dairy proteins are exclusive to dairy proteins due to characteristics of high digestibility or structures which favor phenolic interaction, or if similar effects would be observed with proteins from other sources. Increasing consumer demand for alternative protein sources for reasons pertaining to human health and environmental sustainability has introduced a variety of novel plant-based proteins to the American diet, which may elicit similarly advantageous matrix effects on the bioavailability of polyphenols depending on their digestibility and structural characteristics. Understanding protein-polyphenol interactions in novel food matrices is necessary for the development of food products that promote polyphenol consumption and bioavailability with the aim to improve human health.

• Study Type: Interventional
• Enrollment (Actual): 19
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Colorado
    • Fort Collins, Colorado, United States, 80523-1571
      • Food and Nutrition Clinical Research Laboratory - CSU Gifford Building

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Aged 18 years or older

Exclusion Criteria:

• • Blood levels of HbA1c ≥ 6.5%, total cholesterol ≥ 240 mg/dL, LDL cholesterol ≥ 130 mg/dL, triglycerides ≥ 200 mg/dL

  • Are anemic (hemoglobin less than 13.5 g/dL in men and 12.0 g/dL in women)
  • Have an average blood pressure greater than or equal to 130/80 mmHg, or have diagnosed hypertension, hyperlipidemia, cardiovascular disease, diabetes, cancer, kidney, liver, gastrointestinal or pancreatic disease
  • Taking blood pressure-, lipid- or glucose-lowering, or hormone replacement medications
  • Are pregnant or are trying to become pregnant
  • Have a body mass index < 18.5 or > 30 kg/m2
  • >3 days/week vigorous exercise
  • Are not willing to maintain your normal eating/drinking and exercise habits over the duration of the study
  • History of smoking cigarettes in past 12 months
  • Binge and/or heavy drinker (>3 drinks on any given occasion and/or >7 drinks/week for women, and >4 drinks on any given occasion and/or >14 drinks/week for men)
  • Have allergies or contraindication to study treatments, procedures, or procedure supplies
  • Unable to attend study visits.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Blueberries; Freeze-dried blueberry powder	Dietary supplement: Blueberries; 22 g freeze-dried blueberry powder mixed with water
Active Comparator: Blueberries and Whey Protein; Freeze-dried blueberry powder and whey protein	Dietary supplement: Blueberries and Whey Protein; 22 g freeze-dried blueberry powder mixed with whey protein and water
Active Comparator: Blueberries and Pea Protein; Freeze-dried blueberry powder and pea protein	Dietary supplement: Blueberries and Pea Protein; 22 g freeze-dried blueberry powder mixed with pea protein and water
Active Comparator: Blueberries and Hemp Protein; Freeze-dried blueberry powder and hemp protein	Dietary supplement: Blueberries and Hemp Protein; 22 g freeze-dried blueberry powder mixed with hemp protein and water

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma polyphenol metabolites	Plasma polyphenol metabolite analysis using mass spectrometry	Change from 0 hours (pre-treatment consumption) to 1 hour post-treatment consumption
Plasma polyphenol metabolites	Plasma polyphenol metabolite analysis using mass spectrometry	Change from 0 hours (pre-treatment consumption) to 2 hours post-treatment consumption
Plasma polyphenol metabolites	Plasma polyphenol metabolite analysis using mass spectrometry	Change from 0 hours (pre-treatment consumption) to 4 hours post-treatment consumption
Plasma polyphenol metabolites	Plasma polyphenol metabolite analysis using mass spectrometry	Change from 0 hours (pre-treatment consumption) to 6 hours post-treatment consumption
Plasma polyphenol metabolites	Plasma polyphenol metabolite analysis using mass spectrometry	Change from 0 hours (pre-treatment consumption) to 24 hours post-treatment consumption

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Urine polyphenol metabolites	Urine polyphenol metabolite analysis using mass spectrometry	0 hours (pre-treatment consumption) and 24 hours post-treatment consumption

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gut microbial analysis	16S rRNA gene sequencing	0 hours (pre-treatment consumption) and 24 hours post-treatment consumption
Blood pressure	Brachial blood pressure parameters (systolic, diastolic, and pulse pressure)	0 hours (pre-treatment consumption) and 1, 2, 4, and 6 hours post-treatment consumption
Aortic pressure	Aortic pressure parameters (systolic pressure, aortic pressure, pulse pressure)	0 hours (pre-treatment consumption) and 1, 2, 4, and 6 hours post-treatment consumption
Augmentation index	Augmentation index measured via SphygmoCor Xcel	0 hours (pre-treatment consumption) and 1, 2, 4, and 6 hours post-treatment consumption
Glucose	Blood glucose will be assessed using standard assays	0 hours (pre-treatment consumption) and 1, 2, 4, 6, and 24 hours post-treatment consumption
Insulin	Blood insulin will be assessed using standard assays	0 hours (pre-treatment consumption) and 1, 2, 4, 6, and 24 hours post-treatment consumption
Nitric oxide metabolites	Blood nitric oxide metabolites will be assessed using standard assays	0 hours (pre-treatment consumption) and 1, 2, 4, 6, and 24 hours post-treatment consumption

Collaborators and Investigators

• Sponsor: Colorado State University
• Collaborators: United States Department of Agriculture (USDA)
• Investigators: Principal Investigator: Sarah A Johnson, PhD, RDN, Colorado State University, Department of Food Science and Human Nutrition; Principal Investigator: Charlene Van Buiten, PhD, Colorado State University, Department of Food Science and Human Nutrition

Publications and helpful links

General Publications

• Chima B, Mathews P, Morgan S, Johnson SA, Van Buiten CB. Physicochemical Characterization of Interactions between Blueberry Polyphenols and Food Proteins from Dairy and Plant Sources. Foods. 2022 Sep 14;11(18):2846. doi: 10.3390/foods11182846.

Study record dates

Study Major Dates

• Study Start (Actual): March 9, 2023
• Primary Completion (Actual): July 26, 2023
• Study Completion (Actual): June 1, 2024

Study Registration Dates

• First Submitted: June 22, 2023
• First Submitted That Met QC Criteria: July 20, 2023
• First Posted (Actual): August 1, 2023

Study Record Updates

• Last Update Posted (Actual): June 6, 2024
• Last Update Submitted That Met QC Criteria: June 5, 2024
• Last Verified: June 1, 2024

More Information

Terms related to this study

• Keywords: Adults; Healthy; Bioavailability; Protein; Polyphenols; Blueberries
• Other Study ID Numbers: 3647

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No