Nutrigenomic strategy for identifying food components after ingestion of milk products in humans and their impact on heath parameters

The health promoting benefits of the fermented milk, yoghurt, are well-established. Moreover this product with or without the addition of probiotic bacterial strains has recently been proposed to modulate parameters of metabolic health. Multiple mechanisms may explain these effects including the bacterial action on the release of bioactive metabolites from milk (during the process of fermentation and digestion in the gut), as well as direct interaction of bacteria with the intestinal microflora.

A pilot clinical study was selected for this project as an appropriate initial approach to enable a detailed evaluation of the described relationship between yoghurt and metabolic health. Using a double blinded cross-over design, this study aims to test the response of fourteen healthy male volunteers to a liquid yoghurt containing a known probiotic (Lactobacillus rhamnosus GG) versus a control product (an acidified non-fermented milk). Both products are tested after a single dose (800ml) and after two weeks of daily consumption (400ml/day). In the first single dose test, the post-prandial response to the product is evaluated over six hours. In the second test, the effect of daily consumption of each product on fasting analyses is evaluated as well as the postprandial response to a high fat meal known to induce a transient inflammatory response.

An extensive approach of evaluation is planned to establish the metabolic response to ingestion of the probiotic yoghurt. Nutrikinetic assessments in the postprandial phase of ingestion will primarily address the immediate impact of the food metabolome on the serum metabolome. Conversely, nutridynamic assessments will consider the chronic effect of the product on parameters of metabolic health, intestinal microflora changes, response to inflammatory stress and fasting serum metabolome. The identification of specific biomarkers and metabolic pathways that are regulated by probiotic yoghurt intake may enable a more targeted selection of probiotic strains to increase the efficacy of probiotic yoghurt in improving the metabolic health.