The Effects of Added Sugar Intake on Brain Blood Flow and Hippocampal Function in Midlife Adults

Aging Clinical Trial

Official title:

The Effects of Added Sugar Intake on Brain Blood Flow and Hippocampal Function in Midlife Adults

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05211726
• Other study ID #: 1760500
• Secondary ID: P20GM113125
• Status: Completed
• Phase: N/A
• Start date: January 4, 2022
• Est. completion date: May 3, 2024

Study information

• Verified date: May 2024
• Source: University of Delaware
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study will focus on improving brain health through dietary modification of added sugars in middle aged adults (50- 64 years old). Participants will be fed two 10-day diets (one diet containing 5% of total energy from added sugars and one diet containing 25% of total energy from added sugars) and examine blood vessel function, hippocampus structure using a MRI, and memory performance.

Description:

Aging is the primary risk factor for Alzheimer's disease (AD) which is the most common form of dementia and among the fastest growing causes of morbidity and mortality in the United States. The risk factors for AD emerge during midlife and are similar to cardiovascular and cerebrovascular diseases. The impact of midlife peripheral vascular changes on cardiovascular risk are worsened by poor lifestyle habits, including eating a diet that contains a lot of added sugars (defined as all caloric sweeteners added to food during processing or preparation). One effect of eating a high added sugar diet is an elevation in blood triglycerides (TGs), which impairs blood vessel function by causing inflammation; however, it is not known whether eating a lot of added sugars affects the blood vessels in the brain. The purpose of this project is to determine if there is a link between added sugar intake and brain health in midlife adults. Our hypothesis is that eating excess added sugar impairs the structure and function of an area of the brain called the hippocampus by increasing plasma TGs and systemic inflammation. To test this, we will have people eat a high and low sugar diet for 10 days each (in a random order) and test how each diet affects their blood vessel function, the structure of their hippocampus, and their memory performance. We expect to show that eating a diet that contains a lot of added sugars worsens brain health compared to a diet that contains few added sugars. The data generated from this project will help us better understand risk factors for dementia and will be used to support a future grant proposal to the National Institutes of Health aimed at lowering added sugar intake in mid-life adults and individuals with mild cognitive impairment.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 39
• Est. completion date: May 3, 2024
• Est. primary completion date: May 3, 2024
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 50 Years to 64 Years

Eligibility

Inclusion Criteria:

• ability to provide informed consent;

• men and postmenopausal women aged 50-64 years;

• habitual intake of added sugars =15% of total calories;

• systolic BP < 130 mmHg; diastolic BP < 90 mmHg;

• body mass index (BMI) <30 kg/m2 and % body fat < 25% for men and < 33% for women;

• fasting triglycerides < 200 mg/dl (< 2.3 mmol/L);

• LDL cholesterol <160 mg/dl (4.14 mmol/L);

• fasting plasma glucose <126 mg/dl (<7.0 mmol/L) and hemoglobin A1C < 6.5% at screening;

• weight stable in the prior 6 months (= 2 kg weight change);

• blood chemistries indicative of normal liver enzymes and renal function (estimated glomerular filtration rate using the MDRD prediction equation must be >60 ml/min/1.73 m^2).

Exclusion Criteria:

• current use of medications or supplements known to lower blood triglycerides or cholesterol (e.g., fibrates, statins, high dose niacin, high dose omega-3 supplement);

• chronic clinical diseases (e.g., coronary artery/peripheral artery/cerebrovascular diseases, heart failure, diabetes, chronic kidney disease requiring dialysis, neurological or autoimmune conditions affecting cognition (e.g. Alzheimer's disease or other form of dementia, Parkinson's disease, epilepsy, multiple sclerosis, large vessel infarct);

• major psychiatric disorder (e.g. schizophrenia, bipolar disorder);

• major depressive disorder (PHQ-9 = 10);

• current or past (i.e., last 3 months) use of anti-hypertensive or other cardiovascular-acting medications known to influence vascular function and/or arterial stiffness;

• current medication use likely to affect CNS functions (e.g. long active benzodiazepines);

• concussion within last 2 years and = 3 lifetime concussions;

• heavy alcohol consumption (defined by the CDC and USDA as =8 drinks/week for women and =15 drinks/week for men).

• claustrophobia, metal implants, pacemaker or other factors affecting feasibility and/or safety of MRI scanning;

• recent major change in health status within previous 6 months (i.e., surgery, significant infection or illness);

• current smoking within the past 3 months;

• High degree of physical activity as defined by = 25 leisure MET-hours/week, within the past 3 months.

Related Conditions & MeSH terms

• Aging
• Healthy Diet

Intervention

Other:
• Low Added Sugar Diet
Consumption of 10 days of a diet low in added sugars (5% of total caloric intake)
• High Added Sugar Diet
Consumption of 10 days of a diet high in added sugars (25% of total caloric intake)

Locations

Country	Name	City	State
United States	University of Delaware	Newark	Delaware

Sponsors (2)

Lead Sponsor	Collaborator
University of Delaware	National Institute of General Medical Sciences (NIGMS)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change from baseline in systolic blood pressure at the end of each diet	24-hour ambulatory blood pressure	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Primary	Change from baseline in arterial compliance at the end of each diet	Carotid artery compliance will be calculated as the change in cross sectional area of the carotid artery for a given change in carotid pressure using transcutaneous tonometry coupled with duplex ultrasound	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Primary	Change from baseline in cerebrovascular reactivity at the end of each diet	Total cerebral perfusion measured using pseudo-continuous arterial spin labeling in response to 3-minutes of hypercapnia (+9 mmHg increase in PETCO2)	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Primary	Change from baseline in hippocampal stiffness at the end of each diet	Magnetic Resonance Imaging (MRI) of the brain to collect structural T1- and T2-weighted images	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Primary	Change from baseline in hippocampal damping ratio at the end of each diet	Magnetic Resonance Elastography (MRE) of the brain to collect microstructural integrity while the head will be vibrated using the resoundant acoustic driver system	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Primary	Change from baseline in delayed recall memory (e.g.words) at the end of each diet	Administration of the Hopkins Verbal Learning Test (HVLT-R)	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Primary	Change from baseline in delayed recall memory (e.g. pictures) at the end of each diet	Administration of the Brief Visuospatial Memory Test (BVMT-R)	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Secondary	Change from baseline in pulse wave velocity at the end of each diet	Pulse wave velocity measured using transcutaneous tonometry	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Secondary	Change from baseline in cognitive domain (e.g. processing speed) at the end of each diet	Administration of the NIH Toolbox Pattern Comparison test	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Secondary	Change from baseline in cognitive domain (e.g. inhibition) at the end of each diet	Administration of the NIH Toolbox Flanker test	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Secondary	Change from baseline in lipid profile at the end of each diet	Blood biomarkers of lipid profile (e.g. cholesterol, triglycerides, HDL, LDL, and VLDL)	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Secondary	Change from baseline in inflammation at the end of each diet	Blood biomarkers of inflammation (e.g. cytokines and interleukins)	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Secondary	Change from baseline in oxidative stress at the end of each diet	Blood biomarkers of oxidative stress (e.g. superoxide)	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period
Secondary	Change from baseline in sleep quality compared to each diet	Sleep quality will be continuously measured for 10 days using an Actiwatch.	Over 1.5 months. Once at baseline and again at the end of each 10 day diet (low and high added sugar), separated by a 2 week washout period