Impact of Grape Powder Consumption on Eye Health and Glycemic Status in Singapore Older Adults

National University of Singapore

Status: Enrolling

Conditions: Aging; Advanced Glycation End Products; Macula; Degeneration

Treatments: Dietary Supplement: Freeze-dried table grape powder; Dietary Supplement: Placebo grape powder

Study type: Interventional

Funder types: Other

Identifiers

NCT06349304

S25

Details and patient eligibility

About

The purpose of this study is to understand the impacts of regular consumption of freeze-dried table grape powder on eye health and regulation of advanced glycation end products in Singapore older adults. The investigators hypothesize that regular consumption of freeze-dried table grape powder will promote improvements in eye health and lower levels of advanced glycation end products when compared to the placebo group.

Full description

The study will be a 16-week, double-blind, randomized, placebo-controlled trial using a parallel study design. 46 adults (aged 60 - 85) will be recruited and randomly assigned to the intervention or placebo group to investigate whether regular consumption of freeze-dried table grape powder (46g/d) can improve eye health parameters, blood/skin AGE and glycemic status, and reduce inflammation and oxidative stress. This study will consist of 1 screening visit and 5 study visits with 4-week intervals.

Enrollment: 46 estimated patients

Sex: All

Ages: 60 to 85 years old

Volunteers: Accepts Healthy Volunteers

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

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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46 participants in 2 patient groups, including a placebo group

Freeze-dried table grape powder

Experimental group

Description:

Subjects in this group will be given pouches, each containing 46 g of freeze-dried table grape powder, with an instruction sheet on how to prepare the powder into a drink for consumption.They will consume one pouch a day.

Treatment:

Dietary Supplement: Freeze-dried table grape powder

Placebo table grape powder

Placebo Comparator group

Description:

Subjects in this group will be given pouches, each containing 46 g of placebo grape powder, with an instruction sheet on how to prepare the powder into a drink for consumption.They will consume one pouch a day.

Treatment:

Dietary Supplement: Placebo grape powder