NCT01634841

Walnuts and Healthy Aging

Effect of Daily Ingestion of Walnuts for 2 Years on Age-related Cognitive Decline and Macular Degeneration in Healthy Elderly Subjects: A Randomized, Single Blind, Dual Center, Controlled Trial

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 708 (actual)
• Sponsor: Loma Linda University · Academic / Other
• Sex: All
• Age: 63 Years – 79 Years
• Healthy volunteers: Accepted

Summary

This will be a systematic investigation of the role of walnuts in preventing or slowing age related cognitive decline and age related macular degeneration. 700 subjects will be recruited between 2 sites, Loma Linda University in California, USA and Hospital Clinic in Barcelona, Spain. Participants will be randomly assigned to either the walnut group or the control group for a 2 year intervention. Baseline and annual data will be collected and analyzed.

Detailed description

Epidemiological studies suggest that nutrients such as n-3 polyunsaturated fatty acid, antioxidants and B-vitamins may protect against age related cognitive decline. Small human studies have shown beneficial effects of polyphenol rich foods on cognition and age related macular degeneration. Walnuts are a rich source of n-3 polyunsaturated fatty acid, alpha-linolenic acid, antioxidants, polyphenols and other bioactive compounds. A 2-year intervention will be conducted with healthy, elderly subjects to investigate the role of walnuts in preventing or slowing age related cognitive decline and age related macular degeneration. 350 subjects, age 63 to 79 years, will be recruited at each of 2 sites, Loma Linda University in California and Hospital Clinic in Barcelona. Participants will be randomly assigned to one of two groups: walnut group (habitual diet with 1 or 2 oz/d walnut supplement) or control group (habitual diet only). At baseline and yearly, cardiometabolic risk factors, red blood cell membrane fatty acids, urinary polyphenols and biomarkers of inflammation and oxidation will be measured. Eye exam, blood pressure and cognitive function tests will be measured at the beginning and end of 2 years. At the Barcelona site only, participants will be given a brain MRI and carotid ultrasound. Descriptive results will be reported as mean plus/minus standard deviation. Primary analysis will be carried out on the basis of groups as randomly assigned. Results will be presented as appropriate effect sizes with a measure of precision (95% CI). Analysis of covariates gender, age, educational status will be conducted.

Conditions

• Age Related Cognitive Decline
• Age Related Macular Degeneration

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Walnuts	30 to 60g (1 to 2 oz) per day of walnuts
OTHER	habitual diet	Dietary information will be provided

Timeline

• Start date: 2012-04-01
• Primary completion: 2016-05-01
• Completion: 2016-05-01
• First posted: 2012-07-06
• Last updated: 2021-06-24

Locations

2 sites across 2 countries: United States, Spain