Obesity
Conditions
Keywords
sweeteners, glucose metabolism, taste receptors, sucralose
Brief summary
Data from several studies show that consuming a diet high in low-calorie sweeteners (LCS), mainly in diet sodas, is linked to the same metabolic disorders as consuming a diet high in added sugars, including an increased risk of developing type 2 diabetes. Sweet taste receptors, once thought to be unique to the mouth, have now been discovered in other parts of the body, including the intestine and the pancreas, where they play a role in blood sugar control. These newly identified receptors provide new avenues to explore how LCS may affect metabolism and health. This project is designed to examine the role of sweet taste signaling, both in the mouth and in the gut, on blood sugar control and how habitual consumption of LCS may affect sweet taste signaling and metabolism in people with obesity.
Detailed description
The overall goal of this research is to assess the role of oral and gut sweetness signaling in postprandial glucose metabolism and to determine how acute and chronic low-calorie sweetener (LCS) consumption may affect this signaling in people with obesity. The aims will determine the independent and combined contributions of pharmacological inhibition (Aim 1) or extra stimulation (Aim 2) of sweet taste signaling in the gut, mouth, or both on hormonal responses to an oral glucose tolerance test (OGTT) in two groups of subjects with obesity: habitual and non-habitual LCS consumers. Validated sensory evaluation techniques will also ascertain subjects' taste perception (Aim 3) to test the hypotheses that habitual consumption of LCS blunts perception of sweetness and, in turn, affects postprandial glucose regulation.
Interventions
OTHERControl - Inhibition
Taste and spit up water 10 minutes before drinking a glucose load
OTHERExperimental I- Inhibition
Taste and spit up water 10 minutes before drinking a glucose load mixed with lactisole
OTHERExperimental II- Inhibition
Taste and spit up sucralose 10 minutes before drinking a glucose load mixed with lactisole
OTHERControl- Stimulation
Taste and spit up water 10 minutes before drinking a glucose load
OTHERExperimental I- Stimulation
Taste and spit up sucralose 10 minutes before drinking a glucose load
OTHERExperimental II- Stimulation
Drink sucralose 10 minutes before drinking a glucose load
OTHERSensory Evaluation
Taste different solutions to evaluate sweet taste preference, suprathreshold intensity and detection threshold
Sponsors
Washington University School of Medicine
University of Illinois at Urbana-Champaign
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
21 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
* All races/ethnicities * Habitual (\> 5 diet sodas per week) and non-habitual (≤1 diet soda or 1 packet of LCS per week) LCS consumers * 30 ≤ BMI \<40 kg/m2 * Not severely insulin resistant (HOMA-IR2 \< 2.6)
Exclusion criteria
* BMI \< 30 and 40\< BMI kg/m2 * HOMA-IR2\>2.6 * Irregular LCS consumers (\>1 diet sodas or packets of LCS per week but \<5) * Current smokers or quit smoking nicotine cigarettes for less than 6 months ago * Pregnant, breastfeeding, menopausal * Presence of anemia : \<12g/dl for women and \<13g/dl for men * Blood donation in the past 8 weeks * Presence of malabsorption syndrome * History of bariatric surgery * Presence of inflammatory intestinal disease, liver or kidney disease * Have diabetes (fasting glucose level \>126mg/dl or plasma glucose level 2h after glucose challenge \>200 mg/dl) * Taking any medication that might affect glucose metabolism or the results of our study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Plasma Glucose | Up to 5 hours after drinking a glucose load | Blood samples will be collected before and for 5 hours after drinking a glucose load to determine plasma glucose concentration |
| Plasma Insulin | Up to 5 hours after drinking a glucose load | Blood samples will be collected before and for 5 hours after drinking a glucose load to determine plasma insulin concentration |
| Plasma C-Peptide | Up to 5 hours after drinking a glucose load | Blood samples will be collected before and for 5 hours after drinking a glucose load to determine plasma C-peptide concentration |
| Sensory Evaluation | Up to 2 hours | Participants will be tasting solutions containing different concentrations of glucose, sucrose and sucralose (some of the solutions will also have lactisole) to assess their detection threshold, sweet taste intensity and preference. They will have to rate the intensity of the solution on a general Labeled Magnitude Scale (gLMS) ranging from no sensation (0) to strongest imaginable sensation (100) and choose the solutions they prefer. |
Countries
United States
Contacts
Primary ContactMarta Y Pepino, PhD
Backup ContactClara Salame, MSc, RD
Outcome results
None listed