Mastication, Nutrition
Conditions
Keywords
mastication, postprandial thermogenesis, autonomic nervous system, cephalic phase reflex, food texture
Brief summary
The objective of the study is to analyze the specific role of physical properties of food and mastication in the cephalic phase reflex of thermogenesis, and the involvement of the autonomic nervous system in the implementation of this reflex. The hypothesis of the study is that oral stimulation elicited by food properties during mastication can generate changes in the amplitude of variation of thermogenesis, and that these changes are distinct from those attributable to the thermal effect of food during digestion.
Detailed description
A group of 12 subjects presenting a normal weight and a group of 12 obese subjects, with a good general health and a good dental state will be constituted. They will participate to 5 different recording sessions during which they will be invited to chew and spit out foods and chewing gums of different hardness. During recording sessions with mastication and no-mastication periods, gas exchange (O2 concentration), cardiac activity (electrocardiography) and muscular activity of masticatory muscles (electromyography) will be recorded. Blood samples will be collected during one of the sessions to analyse the kinetic of appearance of some hormones in the blood compartment during or just after mastication. The selected hormones are involved in the eating behaviour and its regulation (ghrelin, peptide C, peptide YY and glucose-like peptide 1). From these recordings, energy expenditure, heart rate variability, intensity of masticatory muscle contraction, and hormone blood appearance will be analysed in link with the nature and hardness of the food chewed. Since the food bolus is spit out after mastication (without any swallowing = sham-feeding), the changes observed in theses variables will be directly attributed to sensory information coming from oral cavity during mastication. Food choice and sport activity of each volunteer will be taken into account to compare the results obtained for the two groups (normal weight and obese). The work will produce more data and evidence on the contribution of oral signals attributable to the food in the regulation of the energy balance. The results will also bring more knowledge on the involvement of the autonomic nervous system. Comparison of the results obtained for the two groups (normal weight and obese people), will bring some positive outcomes which could be useful in the fight against obesity.
Interventions
OTHERMastication
Simultaneous recordings of postprandial thermogenesis (gas exchange), cardiac activity (ECG), masticatory muscle contraction (EMG), and blood collection, during alternating periods of no-mastication or mastication of natural foods or chewing gums of different hardness
Sponsors
Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement
Centre de Recherche en Odontologie Clinique (CROC), Faculté Dentaire
CHU Saint Etienne Nord, Service de Physiologie Clinique et Exercice
University Hospital, Clermont-Ferrand
Study design
Allocation
RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Intervention model description
each volunteer will participate to the whole protocol, that is 5 recording sessions, which, except the first session, will be organized in a random order for each volunteer
Eligibility
Sex/Gender
MALE
Age
20 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
: 19 \< body mass index \< 25 kg/m2 for the normal weight group 30 \< body mass index \< 35 kg/m2 for the obese group Good general health
Exclusion criteria
: * sport activity * Smoking in the 6 months before the beginning of the study * Regular alcohol consumption (more than 4 unit/day) * Medication that may interfere with the results of the study (beta-blockers, corticoids, anti-inflammatories, thyroid hormone, insulin, antiarrhythmics) or that may have an effect on salivation or muscular activity * Oral or dental pathology (including pain), current oral care * Orthodontic treatment in the 3 years before the study * Weigh gain or weight loss of more than 10% in the 3 last months * Thyroid disturbance * High blood pressure * Cardiac activity anomaly * Anomaly for one of the biological elements : complete blood count, fasting blood glucose, glycated haemoglobin, thyroid hormone (TSH), sedimentation rate \> 8mm, CRP rate \> 10ml/L * Allergies, intolerance or disgust for one of the food tested
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Measure of energy expenditure by Indirect calorimetry | 1 hour 30 minutes | effect of mastication without swallowing on energy expenditure (kcal/24h) in normal weight and obese people. This will be measured by indirect calorimetry (Under Canopy of the system Fitmate) |
| Measure of cardiac activity | 1 hour 30 minutes | effect of mastication without swallowing on cardiac activity (R-R interval) in normal weight and obese people measured by electrocardiogram |
| Measure of masticatory muscle activity | 1 hour 30 minutes | effect of mastication without swallowing on masticatory muscle activity (microvolt.s in normal weight and obese people measured by electromyography |
| Estimate of the hormonal response | 1 hour 30 minutes | effect of mastication without swallowing on hormonal response in normal weight and obese people. This will be estimate by their concentration and their kinetic of appearance in the blood compartment, and by comparisons of concentration values with basal level, also expressed in area under the curve values. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| effect of sensory information from oral cavity on masticatory muscle activity | 1 hour 30 minutes | effect of various oral information coming from oral cavity during mastication (food hardness, type of food…) on masticatory muscle activity (microvolt.s) in normal weight and obese people. This will be measured by electromyography |
| cardiac activity while sleeping measured by electrocardiogram | 8-10 hours (night) | evaluation of the general tonus of the autonomic nervous system in normal weight and obese people (R-R interval measured by electrocardiogram) |
| global characterization of food choices | 4 consecutive days | evaluation of the mean energy expenditure in link with food choices and food habits (food portion, score), to have a global characterization of the volunteer. This will be done by the app WellBeNet wich contains NutriQuantic for food choices |
| global characterization of sport activity | 4 consecutive days | evaluation of the mean energy expenditure in link with physical activity (kcal/time unit) to have a global characterization of the volunteer. This will be done by the app WellBeNet wich contains eMouv for sport activities. |
| cardiac activity (frequency analysis) while sleeping measured by electrocardiogram | 8-10 hours (night) | evaluation of the general tonus of the autonomic nervous system in normal weight and obese people |
| effect of sensory information from oral cavity on energy expenditure by Indirect calorimetry | 1 hour 30 minutes | effect of various oral information coming from oral cavity during mastication (food hardness, type of food…) on energy expenditure (kcal/24h) in normal weight and obese people. This will be measured by indirect calorimetry (Under Canopy of the system Fitmate) |
| effect of sensory information from oral cavity on cardiac activity | 1 hour 30 minutes | effect of various oral information coming from oral cavity during mastication (food hardness, type of food…) on cardiac activity (R-R interval) in normal weight and obese people. This will be measured by electrocardiogram. |
| effect of sensory information from oral cavity on hormonal response | 1 hour 30 minutes | effect of various oral information coming from oral cavity during mastication (food hardness, type of food…) on hormonal response in normal weight and obese people. This will be estimate by their concentration and their kinetic of appearance in the blood compartment, and by comparisons of concentration values with basal level, also expressed in area under the curve values. |
Countries
France
Contacts
Primary ContactPatrick LACARIN
Outcome results
None listed