Inclusion Criteria:  ability to provide informed consent; men and postmenopausal women aged 50-64 years; habitual intake of added sugars between 12-15% of total calories; systolic BP < 130 mmHg; diastolic BP < 90 mmHg; body mass index (BMI) <30 kg/m^2 and % body fat < 25% for men and < 33% for women fasting triglycerides < 150 mg/dl (< 1.7 mmol/L); total cholesterol <240 mg/dl (<6.2 mmol/L); fasting plasma glucose <100 mg/dl (<5.1 mmol/L) and hemoglobin A1C < 5.7% at screening; weight stable in the prior 6 months (≤ 2 kg weight change); blood and urine 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); Currently taking hormone replacement therapy; 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.