NCT01297738

Diet, Insulin Sensitivity And the Brain

The Effect of Dietary Patterns and Diet Composition on Insulin Sensitivity and Cerebral Dopamine- and Serotonin Transporters

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 39 (actual)
• Sponsor: Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA) · Academic / Other
• Sex: Male
• Age: 18 Years – 40 Years
• Healthy volunteers: Accepted

Summary

Obesity and insulin resistance may be in part explained by an altered reward system with changes in the serotonin/dopamine system. These changes might be caused by changes in dietary habits, especially by an increased intake of liquid sugar and an increase in meal frequency. The investigators hypothesize that increasing meal frequency compared to increasing meal size and when consuming a hypercaloric high-sugar diet (HS) compared to a hypercaloric high-fat-high-sugar diet (HFHS) will result in a reduction in cerebral serotonin and dopamine transporters and in a more prominent increase in insulin resistance. In addition, the investigators hypothesize that the changes in insulin sensitivity will be independent of changes in abdominal (visceral) and liver fat and that changes in insulin sensitivity due to the dietary manipulation will co-occur with changes in insulin signaling pathways in peripheral fat and muscle tissue.

Detailed description

Lean, healthy, young men will follow a hypercaloric HF- or HFHS diet for 6 weeks. Before and after the dietary intervention, the investigators will perform a SPECT-scan for serotonin and dopamine transporters with the radioligand \[123I\]FP-CIT, administered intravenously. The investigators will also perform a structural MRI for localization. Furthermore the investigators will perform a liver MRS and abdominal MRI for liver fat- and abdominal visceral fat measurement. The investigators will also perform a euglycemic, hyperinsulinemic clamp to measure insulin sensitivity and muscle- and fat biopsies to examine changes in insulin signaling pathways and fat metabolism. After the hypercaloric diet subjects will follow a hypocaloric diet until their weight is back to baseline.

Conditions

• Obesity
• Diabetes Mellitus Type 2

Interventions

Type	Name	Description
OTHER	Meal size increase with HFHS	On top of a healthy, eucaloric diet, study subjects consume a 40% calory surplus by consuming a high-fat, high-sugar liquid medical food supplement (Nutridrink®). Subjects consume the Nutridrink® with their meals, which results in an increase in meal size.
OTHER	Meal size increase with HS	On top of a healthy, eucaloric diet, study subjects consume a 40% calory surplus by consuming commercially available sugar-sweetened beverages. Subjects consume these sugar-sweetened beverages with their meals, which results in an increase in meal size.
OTHER	Meal frequency increase with HFHS	On top of a healthy, eucaloric diet, study subjects consume a 40% calory surplus by consuming a high-fat, high-sugar liquid medical food supplement (Nutridrink®). Subjects consume the Nutridrink® 3 times a day in between meals, which results in an increase in meal frequency.
OTHER	Meal frequency increase with HS	On top of a healthy, eucaloric diet, study subjects consume a 40% calory surplus by consuming commercially available sugar-sweetened beverages. Subjects consume these sugar-sweetened beverages 3 times a day in between meals, which results in an increase in meal frequency.

Timeline

• Start date: 2011-02-01
• Primary completion: 2012-07-01
• Completion: 2012-07-01
• First posted: 2011-02-17
• Last updated: 2013-01-24

Locations

1 site across 1 country: Netherlands