Bioavailability of Carotenoids – Impact of High Mineral Concentrations

Study Objective

Post prandial study to test the impact of high calcium intake on the bioavailability of dietary carotenoids.

The main endpoint of this study is to measure the post prandial Area-Under-the-Curve (AUC) and concentration of circulating carotenoids in the plasma triglyceride-rich lipoprotein (TRL) fraction, a fraction representing newly absorbed carotenoids(Bohn et al. 2011).

Additionally the investigators would like to detect and measure epoxycarotenoid conversion products such as neochrome, luteoxanthin and auroxanthin or additional degradation products in the plasma TRL fraction and to investigate the impact of minerals on their absorption. These epoxycarotenoids constitute a significant part of the consumed daily carotenoids, ca. 15% (Biehler et al. 2012), but their metabolism remains unclear, despite the fact that some of their conversion products are well taken up by the intestinal mucosa (Biehler et al., 2011).

The predicted individual duration of the study will be 4 weeks for the participants (see schedule in Figure 3).

Participants’ schedule during the trial
• Two screening visits are planned:
1st at the enrolment phase,
2nd at the beginning of the trial, each lasting no more than a couple of hours/or half a day 
• Three study visits are foreseen: each lasting a whole day (ca. 11 hours)
For their participation, participants will receive a total of 350€ as a compensation for blood samples and visits.

Participation conditions

Inclusion criteria

o healthy and free living;
o men;
o ages between 19 and 50 years old;
o Body-Mass-Index (BMI) between 18.5 and 25;
o non-smokers (abstinent for more than 2 years).

Exclusion criteria

o suffering from any metabolic disease that may cause digestive disturbances (such as Crohn’s disease or colitis);
o malabsorption disorders;
o BMI over 30 or below 18.5;
o hyperlipidaemia (triglycerides and/or total cholesterol over 200 mg/dl);
o any individuals following a special diet that is not compatible with wash-out periods or test meals (vegetarian, gluten-free or diabetic);
o regular consumption of more than 5 portions (80-100 g) of fruits and vegetables per day;
o being on medical treatment or consuming any medication for chronic conditions or recent illness (e.g. antibiotics);
o consuming regularly dietary supplements;
o abnormally high or low values of plasma circulating carotenoids;
o tobacco smoking;
o frequent alcohol consumption (over 2 glasses per day);
o food allergies or intolerances that are not compatible with test meals (e.g. gluten or milk intolerance);
o daily practice of intense physical activity of 150 min or more.

No special population group such as prisoners, children, the mentally disabled or groups whose ability to give voluntary informed consent may be in question, will be recruited for this study.

CIEC (Centre d’Investigation et d’Epidémiologie Clinique), CRP-Santé
CRP – Gabriel Lippmann (Centre de Recherche Publique Gabriel Lippmann)