Effects of grape powder on eye health and blood sugar in older adults

Impact of Regular Consumption of Grape on Eye Health and Regulation of Advanced Glycation End-products in Singapore Older Adults

Not applicable Interventional National University of Singapore · NCT06349304

This study is testing if eating freeze-dried grape powder can help improve eye health and blood sugar levels in older adults.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment46 (estimated)
Ages60 Years to 85 Years
SexAll
SponsorNational University of Singapore Academic / other
Locations1 site (Singapore)
Trial IDNCT06349304 on ClinicalTrials.gov

What this trial studies

This study investigates the effects of regular consumption of freeze-dried table grape powder on eye health and the regulation of advanced glycation end products in older adults in Singapore. It is a 16-week, double-blind, randomized, placebo-controlled trial involving 46 participants aged 60 to 85. Participants will be randomly assigned to either the grape powder or placebo group to assess improvements in eye health, glycemic status, and inflammation levels. The study includes multiple visits for screening and assessments throughout the trial period.

Who should consider this trial

Good fit: Ideal candidates are older adults aged 60 to 85 who are English-literate and can provide informed consent.

Not a fit: Patients with existing serious eye diseases, diabetes, or those on specific diets or medications may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to dietary recommendations that improve eye health and glycemic control in older adults.

How similar studies have performed: While there have been studies on dietary interventions for eye health, this specific approach using freeze-dried grape powder is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Male and female participants, aged between 60 and 85 years old inclusive
2. English-literate and able to give informed consent in English

Exclusion Criteria:

1. Smokers
2. Allergy to grapes or food dyes/additives, or had serious food allergies in the past
3. Known eye diseases (macular degeneration, cataracts, retinopathy or glaucoma), blindness in at least one eye or have had eye surgery
4. Unable to view bright lights or flashing lights
5. Has Type 1 or 2 diabetes, uremia, cardiovascular disease, abnormal kidney and liver function
6. Taking eye medication and/or dietary supplements for the eyes for the past 3 month
7. Taking supplements containing carotenoids (e.g. Vitamin A, lutein, zeaxanthin) for past 3 months
8. Currently on a specialised diet (e.g. vegetarian, vegan, weight loss diet, low fat diet
9. Consumes more than 2 alcoholic drinks per day i.e. one drink is defined as either 150ml of wine,340ml of beer/cider or 45ml of distilled spirit
10. Significant change in weight (≥ 3 kg body weight) in the past 3 months
11. Significant exercise pattern over the past 3 months defined as high-intensity exercise of more than 3 hours per week
12. Currently on anti-hypertensive, cholesterol-lowering or psychoactive drugs
13. Scored ≤ 7 on the abbreviated mental test
14. Poor peripheral venous access based on past experiences with blood draw
15. Participating in another clinical study

Where this trial is running

Singapore

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions MaculaDegenerationAgingAdvanced Glycation End ProductsVitis viniferaOlder adultsInflammationGlycemic status
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.