Effect of Apples on cardioVascular Risk And Gut Health (AVAG)

Effect of Apples Consumption on Blood Lipid Levels,Vascular Function and Gut Health in Moderate Hypercholesterolemic Subjects

There is now considerable scientific evidence that a diet rich in fruits and vegetables could improve human health. Apples are among the most frequently consumed fruits in the world. Epidemiological studies have linked frequent apple consumption with several health benefits including a reduced risk of cardiovascular disease. Apples are an important source of polyphenols and fiber and their beneficial effects could be attributed to this content; however, their impact on our health is not clear. Although, there are some studies that have reported cholesterol lowering effects the results are inconsistent. Furthermore, few studies have explored the impact on vascular function and gut microbiota. The objective of the current study is to assess whether a regular apple consumption, reduces total cholesterol levels, improves vascular function and gut microbiota profile in mildly hypercholesterolemic subjects compared with a control, sugar matched commercial clear apple juice squash.

Study Overview

• Status: Completed
• Conditions: Mild Hypercholesterolemia
• Intervention / Treatment: Dietary supplement: whole apples (WA); Dietary supplement: apple juice (AJ)

• Study Type: Interventional
• Enrollment (Actual): 40
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Berkshire
    • Reading, Berkshire, United Kingdom, RG6 6AP
      • Department of Food and Nutritional Sciences, University of Reading

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 23 years to 69 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Mildly hypercholesterolemic: TC>5.2 and <7.9 mmol/L
• BMI: 20-35
• Age: 23-69
• Normal liver and kidney function

Exclusion Criteria:

• Drug treatment for hyperlipidaemia, hypertension, inflammation and hypercoagulation.
• Vegetarians.
• Smoking.
• History of alcohol misuse.
• History of food allergy (e.g. apples, sulphites).
• Taking antibiotics for the previous 3 months.
• Taking phytochemical, antioxidant, fish oil supplements, or prebiotic/probiotic preparations unless willing to stop for the study period and after a 4 week wash out period (8 weeks for fish oil).
• Females who are pregnant, lactating, or if of reproductive age and not using a reliable form of contraception (including abstinence).
• Medical history of cardiovascular disease including coronary heart disease (angina and heart attack) and stroke (in the past 12 months).
• Family history of cardiovascular disease (their father or brother was under 55 or their mother or sister was under 65 when they were diagnosed with cardiovascular disease).
• Diabetes mellitus.
• Kidney, liver, pancreas or gastrointestinal diseases.
• Hematologic disorders (i.e. anaemia; men:haemoglobin<13.8g/dl (8.56mmol/L) and women<12.1 g/dl (5.51mmol/L)).
• Planning a weight reducing regime.
• Parallel participation in another dietary intervention study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: whole apples; Subjects are asked to consume 2 apples a day for 8 weeks in addition to their habitual diet	Dietary supplement: whole apples (WA)
OTHER: apple juice squash; Subjects are asked to consume 100 ml of apple juice squash (recommended dilution with water up to 500 ml) for 8 weeks in addition to their habitual diet. The apple juice is used as a sugar matched control.	Dietary supplement: apple juice (AJ)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Changes in blood lipid levels	Baseline and assessment at 8 weeks for each intervention arm including a 4 week wash out period.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evaluation of endothelial function by using laser doppler iontophoresis (LDI)		Baseline and assessment at 8 weeks for each intervention arm.
Changes in vascular stiffness by pulse wave analysis (PWA)		Baseline and assessment at 8 weeks for each intervention arm
Changes in faecal bacterial population		Baseline and assessment at 8 weeks for each intervention arm
Ambulatory blood pressure	Blood pressure will be recorded for 30 minutes at baseline and at 8 weeks for each intervention arm	Baseline and assessment at 8 weeks for each intervention arm
Changes in inflammatory, endothelial function and oxidative stress markers		Baseline and assessment at 8 weeks for each intervention arm
Changes in insulin resistance and gut hormones		Baseline and assessment at 8 weeks for each intervention arm
Metabolomic analysis for the determination of the low molecular weight metabolite profiles in the biological fluids (blood, urine and faecal sample).		Baseline and assessment at 8 weeks for each intervention arm

Collaborators and Investigators

• Sponsor: University of Reading
• Collaborators: Fondazione Edmund Mach di San Michele all'Adige
• Investigators: Principal Investigator: Julie A Lovegrove, BSc, PhD, RNutr, University of Reading; Principal Investigator: Kieran Tuohy, Dr, FEM-IASMA Research and Innovation centre

Publications and helpful links

General Publications

• Koutsos A, Riccadonna S, Ulaszewska MM, Franceschi P, Trost K, Galvin A, Braune T, Fava F, Perenzoni D, Mattivi F, Tuohy KM, Lovegrove JA. Two apples a day lower serum cholesterol and improve cardiometabolic biomarkers in mildly hypercholesterolemic adults: a randomized, controlled, crossover trial. Am J Clin Nutr. 2020 Feb 1;111(2):307-318. doi: 10.1093/ajcn/nqz282.

Study record dates

Study Major Dates

• Study Start: September 1, 2013
• Primary Completion (ACTUAL): October 1, 2014
• Study Completion (ACTUAL): November 1, 2014

Study Registration Dates

• First Submitted: October 10, 2013
• First Submitted That Met QC Criteria: November 11, 2013
• First Posted (ESTIMATE): November 20, 2013

Study Record Updates

• Last Update Posted (ESTIMATE): March 9, 2015
• Last Update Submitted That Met QC Criteria: March 6, 2015
• Last Verified: March 1, 2015

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Metabolic Diseases; Lipid Metabolism Disorders; Hyperlipidemias; Dyslipidemias; Hypercholesterolemia
• Other Study ID Numbers: 13/22; University of Reading (Other Identifier: Reading University)