Condition category
Eye Diseases
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
There is a yellow pigment at the back of the eye (retina) called macular pigment which is believed to be important for improving visual performance and visual comfort. Macular pigment is of dietary origin, i.e. we are not born with macular pigment but we accumulate it
from eating certain fruits and vegetables. Eggs are also a major source of macular pigment. This study is designed to test the benefits of egg consumption on macular pigment levels and vision.

Who can participate?
Thirty healthy volunteers between the age of 18-60 years with normal cholesterol levels will be eligible to take part in this study.

What does the study involve?
Volunteers will be randomly allocated to one of five groups. Volunteers in the four intervention groups will be provided with eggs containing different amounts of the macular pigments, and volunteers in the control group will receive normal non-enriched eggs, to be taken daily for the duration of the study. Each volunteer will visit the study centre on two separate occasions: at the first visit at the start of the study and after two months of eating the eggs. Each study visit will last about two hours. They will be asked to eat a meal containing two eggs each day for eight weeks in total. During the study visit, a blood sample will be taken to measure macular pigment and cholesterol levels in the blood. They will be asked to complete a short questionnaire to gather information that might be important to the status of the eye. A picture of the back and front of the eye will be taken using a specialised camera. They will be asked to fill in a dietary questionnaire, which will find out the macular pigment levels in your diet. They will be required to undergo brain function testing by following simple on-screen instructions on a touch screen computer.

What are the possible benefits and risks of participating?
You will gain knowledge of your macular pigment level. It has been suggested that a person’s macular pigment level is a good indicator of overall eye health. This will be provided at the end of the study. Also, it is possible that society may gain from the results of this study. The brain function test is a non-invasive test and will be achieved using standardised and appropriate memory and reaction tests. We foresee no risks to the subjects participating in this study. However, eggs contain high amounts of cholesterol and therefore a high egg intake (such as in this study) may potentially have a negative impact on subjects with high levels of blood cholesterol. The eggs will be produced in accordance with appropriate food quality standards. However, in the unlikely event that you feel unwell as a result of having the egg at any stage of the study, we would ask you to contact the researcher listed below, who will then follow the appropriate procedures.

Where is the study run from?
The study is run from Carriganore House, West Campus, Waterford Institute of Technology, Ireland.

When is the study starting and how long is it expected to run for?
The study will commence in September 2013 and will be active for 3 months in total.

Who is funding the study?
This study is sponsored by Nutrasight Consultancy Ltd, a local research company located at Arclabs, Waterford Institute of Technology, Ireland.

Who is the main contact?
Ms Katie Meagher

Trial website

Contact information



Primary contact

Prof John Nolan


Contact details

Waterford Institute of Technology
Carriganore House
West Campus

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Egg Xanthophyll Interventional Trial: a randomised controlled study



Study hypothesis

The aim of this study is to measure serum, macular and cognitive responses to supplementation with lutein (L), zeaxanthin (Z) and meso-Z (MZ) fortified eggs.

Ethics approval

This trial was approved by the Waterford Institute of Technology Ethics committee.

Study design

Randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Age-related macular degeneration


Volunteers will be provided with eggs containing different amounts of the macular pigments, or a normal non-enriched egg, to be taken daily for the duration of the study. They are randomised to 5 groups. Fortified eggs will be used as supplements as follows:
Group 1: L fortified egg
Group 2: MZ fortified egg
Group 3: Egg with 1:1 ratio of MZ and L
Group 4: Z fortified egg
Group 5: Standard egg (control egg)

Intervention type



Not Applicable

Drug names

Primary outcome measures

Macular pigment response: measured using the Spectralis OCT (Heidelberg Engineering); cognitive function is measured using CANTAB interactive software (Cambridge Cognition). All measurements will be made for each study visit. Study visits will be completed at baseline and at the end of the trial (week 8).

Secondary outcome measures

Serum carotenoid response: measured using high performance liquid chromatography (HPLC)

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

Eligible subjects will have no ocular pathology, no history of cardiovascular disease, no allergy to egg-containing products, low cholesterol and non-smoking status.

Participant type


Age group




Target number of participants


Participant exclusion criteria

Subjects will only be eligible if they have no recent history of supplementation with the macular carotenoids, or cholesterol-lowering statins.

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Waterford Institute of Technology

Sponsor information


The Howard Foundation (UK)

Sponsor details

c/o HFH Group
PO Box 1187
CB22 5WB
United Kingdom

Sponsor type




Funder type


Funder name

The Howard Foundation, UK

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes