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The Effect of Daily Consumption of Eggs on Cognitive Function in the Elderly

This study has been completed.
Information provided by (Responsible Party):
Tufts University Identifier:
First received: March 13, 2012
Last updated: April 24, 2017
Last verified: April 2017

Cognitive impairment is also a major risk factor for development of dementia later in life. Findings from our studies suggest that the carotenoids, lutein and zeaxanthin may be important in cognitive function in the elderly. The investigators have previously reported eggs to be a highly bioavailable source of lutein and zeaxanthin. Our study evaluates long-term egg intervention as a treatment strategy for age-related cognitive impairment which could possibly prevent the onset of dementia. The investigators have also shown that lutein supplementation significantly improved verbal fluency scores in healthy older women. Our studies have shown that egg interventions can significantly increase serum lutein concentrations in older adults. Based on the sum of our findings, the next logical step will be to investigate the ability of lutein and zeaxanthin contained in eggs to influence cognitive function in older adults. The investigators hypothesize that there will be a significant increase in cognitive function measures in older adults provided with meals containing 2 egg/day at the end of 6 months, while no significant improvements will be observed in older adults given daily meals containing egg substitute.

The proposed study is designed as a randomized, placebo controlled trial that tests the effects of 6 month supplementation with 2 eggs/day on cognitive function in older adults. Secondary analyses will determine whether baseline MP density predicts relative effectiveness of the intervention on cognitive function. Secondary outcomes include plasma biomarkers of oxidative stress and inflammation.

Condition Intervention Phase
Mild Cognitive Impairment
Other: eggs or egg whites
Early Phase 1

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: No masking
Primary Purpose: Prevention
Official Title: The Effect of Consumption of 2 Eggs or 4 oz of Egg Substitute Daily for 6 Months on Cognitive Function in Older Adults.

Further study details as provided by Tufts University:

Primary Outcome Measures:
  • cognition [ Time Frame: 6 months ]
    measures of attention, executive function, verbal fluency will be made using a sensitive computerized program

Secondary Outcome Measures:
  • inflammation [ Time Frame: 6 months ]
    markers of inflammation will be made in plasma

Enrollment: 44
Study Start Date: July 2012
Study Completion Date: August 2015
Primary Completion Date: August 2015 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: egg white (control)
egg whites, 4 ounces
Other: eggs or egg whites
2 eggs/day or 4 oz egg whites/day for 6 months
Experimental: eggs
eggs, 2 large
Other: eggs or egg whites
2 eggs/day or 4 oz egg whites/day for 6 months

Detailed Description:
The study is designed as a placebo controlled trial that tests the effects of 6 month supplementation with 2 eggs or 4 ounces of egg substitute a day on cognitive function in older adults. Subjects will be randomly assigned to one of the two groups. Secondary analyses will determine whether baseline macular pigment density (a non invasive measure of lutein and zeaxanthin in neural tissue) or choline status predicts relative effectiveness of the intervention on cognitive function. Secondary outcomes include plasma biomarkers of oxidative stress and inflammation, choline bioavailability, and genetic variants related to endogenous choline production. Participants will be recruited from community-dwelling men and women aged > 50 yr, and potential participants will be screened to meet cognitive and functional criteria. Participants will be pre-screened by telephone; those who appear to meet criteria will undergo further screening. The study will include baseline (0 month), 3 and 6 month visits for study procedures, and monthly telephone calls. Given that there is a visible difference between the two interventions (eggs, egg substitute), a blinded study is not possible.

Ages Eligible for Study:   50 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • men and women age > 50 years
  • BMI 19-30 kg/m2
  • lutein intake of < 3 mg/d
  • DHA (docosahexaehoic acid) intake < 250 mg/d (including supplements)
  • Mini mental state exam (MMSE) score > 24 (Appendix B)
  • macular pigment density < 0.5 at 0.5 degrees
  • Beck Depression Inventory < 20
  • free of known disease;
  • BMI 19-29 kg/m2
  • must be able to give written informed consent
  • have normal hematologic parameters
  • normal values of plasma albumin
  • normal values for liver and kidney function (Appendix A)
  • no use of carotenoid, n3 fatty acid, multivitamin/mineral, or choline supplements (> 3 months).
  Contacts and Locations
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Please refer to this study by its identifier: NCT01621646

United States, Massachusetts
Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University
Boston, Massachusetts, United States, 02111
Sponsors and Collaborators
Tufts University
Principal Investigator: Elizabeth J Johnson, PhD Tufts University
  More Information

Responsible Party: Tufts University Identifier: NCT01621646     History of Changes
Other Study ID Numbers: 001
Study First Received: March 13, 2012
Last Updated: April 24, 2017

Keywords provided by Tufts University:
mild cognitive impairment

Additional relevant MeSH terms:
Cognition Disorders
Mild Cognitive Impairment
Neurocognitive Disorders
Mental Disorders processed this record on May 23, 2017