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Carotenoid Absorption and Metabolism From Green-leafy Vegetable Matrices

Not Applicable
Terminated
Conditions
Ileostomy; Functional Disturbance
Healthy
Interventions
Dietary Supplement: Spinach - Whole leaf (10 mg lutein)
Dietary Supplement: Spinach - Minced (10 mg/lutein)
Registration Number
NCT02450227
Lead Sponsor
University of Copenhagen
Brief Summary

Absorption and metabolism of carotenoids from two types of spinach preparations will be investigated in two study groups, short bowel/ileostomy and healthy, respectively.

The study will be conducted as a randomised, controlled, 2-way crossover study in 24 participants (12 in each group), randomized to two sequences (1-2, 2-1) of interventions with a more and a less bio-accessible spinach preparation. The serum, chylomicron and fecal/effluent levels of lutein and beta-carotene will be determined.

Detailed Description

Absorption and metabolism of carotenoids from two types of spinach preparations will be investigated in two study groups, short bowel/ileostomy and healthy, respectively.

The study will be conducted as a randomised, controlled, 2-way crossover study. Twenty four participants (12 in each group) will be randomized to two sequences (1-2, 2-1) of interventions with a more and a less bio-accessible spinach preparation (differentiates only on the basis of particle size).

The intervention period is sub-divided into three parts: run-in period (48 hours) with a standardized low-carotenoid diet, 0-24 hours (follow-up period 1 (FP1)) and 24 hours - 2 weeks (FP2). The intervention periods will be separated by a wash-out period of at least 14 days.

At start of each intervention, the intervention meal (breakfast) is served, followed by standardized, carotenoid-free meals in the following 24 hours. Participants will in FP1 and FP2 receive an intervention meal every second day. Participants will otherwise keep their habitual diets during these follow-up periods.

Study participants are asked to collect urine during 24 hours before and after the first intervention meal in each period. They will also collect feces/ileostomy efflux for 24 hours before and after initiation of the intervention for short bowel/ileostomy patients and for 48 periods in the healthy volunteers, respectively. Overnight-fasting serum samples are drawn at day 1, 7 and 15 of each intervention period. On day 1 plasma samples are drawn at 0,1, 3, 4, 6, 7, 9 and 24 hours post first intervention meal.

Plasma and effluent levels of lutein and beta-carotene will be determined and chylomicrons are also separated from these samples for determination of carotenoids.

Volunteers also have their macula examined for density of the yellow spot before and after the intervention. Plasma and effluent levels of other carotenoids as well as fat-soluble vitamins are also determined. The samples will also be subjected to metabolic profiling for further exploration and hypothesis generation.

Recruitment & Eligibility

Status
TERMINATED
Sex
All
Target Recruitment
22
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Spinach - Minced (10 mg lutein)Spinach - Whole leaf (10 mg lutein)2-1: Group given minced spinach as first intervention Minced spinach (10 mg lutein) given every second day for a 15 days period. Followed by: Whole leaf spinach (10 mg lutein) given every second day for a 15 days period.
Spinach - Whole leaf (10 mg lutein)Spinach - Whole leaf (10 mg lutein)1-2: Group given whole leaf as first intervention Whole leaf spinach (10 mg lutein) given every second day for a 15 days period. Followed by: Minced spinach (10 mg lutein) given every second day for a 15 days period.
Spinach - Whole leaf (10 mg lutein)Spinach - Minced (10 mg/lutein)1-2: Group given whole leaf as first intervention Whole leaf spinach (10 mg lutein) given every second day for a 15 days period. Followed by: Minced spinach (10 mg lutein) given every second day for a 15 days period.
Spinach - Minced (10 mg lutein)Spinach - Minced (10 mg/lutein)2-1: Group given minced spinach as first intervention Minced spinach (10 mg lutein) given every second day for a 15 days period. Followed by: Whole leaf spinach (10 mg lutein) given every second day for a 15 days period.
Primary Outcome Measures
NameTimeMethod
Serum concentration of lutein and beta-carotene15 days

Difference in serum concentration of lutein and beta-carotene between baseline and the end of each intervention period.

Secondary Outcome Measures
NameTimeMethod
Concentration of lutein and beta-carotene in the chylomicron/TLR fraction24 hours

Changes in concentration of lutein and beta-carotene in the chylomicron/TLR fraction (area under the curve, AUC) 24 hours post first intervention meal in each intervention periods.

Concentration of other carotenoids in the chylomicron/TLR fraction24 hours

Changes in concentration of other carotenoids in the chylomicron/TLR fraction (area under the curve, AUC) 24 hours post first intervention meal in each intervention periods.

Level of optical density of the macula luteaBaseline

Level of optical density in the macula lutea (MPOD), in the spectra where xanthophyll pigment is absorbing light.

Total lutein and beta-carotene sekretion with feces/ileostomy-efflux48/24 hours

Total lutein and beta-carotene sekretion with feces/ileostomy-efflux 48 and 24 hours postprandial, for healthy and ileostomy patients, respectively.

Serum concentration of other carotenoids15 days

Difference in serum concentration of other carotenoids between baseline and the end of each intervention period.

Serum concentration of other fat-soluble vitamins15 days

Difference in serum concentration of other vitamins (A, E; D, K) between baseline and the end of each intervention period.

Changes in metabolic markers15 days

Changes in overall metabolic markers in serum at the end of each intervention period.

Trial Locations

Locations (2)

Department of Nutrition, Exercise and Sports, University of Copenhagen

🇩🇰

Frederiksberg C, Denmark

Rigshospitalet, Department of Gastroenterology, CA-2121

🇩🇰

Copenhagen Ø, Denmark

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