Bread Daily Intake Enriched With Mix Fibers in Metabolic Subjects: Intestinal Microbiota and Metabolic Profile Impact (Breath)

Bread Daily Intake Enriched With Mix Fibers in Metabolic Subjects: Intestinal Microbiota and Metabolic Profile Impact

Study of the Impact of Daily Bread Consumption Enriched With a Fibre Mix on Intestinal Microbiota and Metabolic Profile in Subjects at Metabolic Risk

The level of fibre consumption in France is lower than the national and international recommendations (mean 18.8 g/d for men, 16.4 g/d for women (INCA 2007 Study) instead of 30g/d recommended). Fibre have beneficial effects on health and interact with the intestinal microbiota diversity: a diet fortified with different structure fibres increase of 25 % the dysbiotic intestinal microbiota in obese patient (Cotillard et al, Dietary intervention impact on gut microbial gene richness. Nature, August 2013). The study aim is to evaluate the impact of daily consumption of bread (150 g ) enriched with a mixture of fibres of different structure (15g) during two months on the intestinal microbiota composition in metabolic risk subjects (abdominal overweight or obese) and also, to assess the correlation between the microbiota change and their metabolic profile improvement.It is a mono centric study with a centre in LYON (Centre de Recherche en Nutrition Humaine Rhône-Alpes)

intestinal microbiota composition will be measured by metagenomic analysis before all interventions, and before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified)

Plasma glucose will be measured in the fasting state and in the post-meal period over 7 hours before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified)

Plasma insulin will be measured in the fasting state and in the post-meal period over 7 hours before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified)

Plasma triglycerides will be measured in the fasting state and in the post-meal period over 7 hours before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified)

Plasma non-esterified fatty acids will be measured in the fasting state and in the post-meal period over 7 hours before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified)

Change from baseline fasting plasma lipids (cholesterol total, cholesterol HDL and LDL) at eight weeks

Fasting plasma lipids will be measured before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified)

CRPus will be measured before and after each eight weeks, consumption sequences (fiber-fortified bread vs unfortified)

MDA will be measured before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified)

Acylated ghrelin will be measured in the fasting state and postprandial period (at 0 and 240 min) before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified)

Satiety response will be measured using subjective perceptions of hunger, fullness, satisfaction, and prospective food intake evaluated by previously validated visual analogue scales (VAS) (on a 90mm horizontal line; from no sensation of satiety (minimal) to strong sensation of satiety (maximum).

Body composition will be measured with bio-impedancemetry before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified)

Resting Energy Expenditure will be measured with indirect calorimetry before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified).

Substrate oxydation (in the postprandial period over 7 hours) will be measured with indirect calorimetry before and after each eight weeks consumption sequence (fibre-fortified bread vs unfortified).

Subjective ratings of bloating, nausea, vomiting, abdominal cramping and flatulence will be measured using visual analogue scale (VAS) score (on a 90mm horizontal line; from no symptom (minimal) to serious symptom (maximum).

Inclusion Criteria: Body Mass Index of 25 to 35 kg/m2 Waist circumference greater than 80 cm for women and than 96 cm for men Low level of fibre intake (<20 g /d) and low level of fibre nature diversity Daily bread consumption Exclusion Criteria: Bread products allergy or intolerance Digestive surgery history except appendicectomy Metabolic or gastrointestinal disease history Medication that could interfere with glucose and lipid metabolism or intestinal microbiota (for example, no antibiotics within the 3 months before the study) Smokers (5 cig/d or more)