Nitrite Supplementation for Improving Physiological Function in Older Adults

Exclusion Criteria

• •• High dietary nitrate intake or current nitrite supplementation; hypersensitivity to nitrates or nitrites
• •* Glucose-6-phosphate dehydrogenase deficiency or blood methemoglobin \>2%
• •* Current smoking
• •* Having past or present alcohol dependence or abuse, as defined by the American Psychiatry Association, Diagnostic and Statistical Manual of Mental Disorders
• •* Body mass index (BMI) \>40 kg/m2 (FMD measurements can be inaccurate in severely obese patients)
• •* Chronic clinical diseases (e.g., coronary artery/peripheral artery/cerebrovascular diseases, diabetes, chronic kidney disease requiring dialysis, neurological disorders or diseases that may affect motor/cognitive functions \[multiple sclerosis, Parkinson's disease, polio, Alzheimer's disease, dementia or other brain diseases of aging\]), except hypertension and hyperlipidemia.
• •* Regular vigorous aerobic/endurance exercise (\>3 vigorous bouts/week)
• •* Not weight stable in the prior 3 months (\>2 kg weight change) or unwilling to remain weight stable throughout study (rationale: recent weight change or weight loss can influence vascular function and small metabolite signature(216))
• •* Current treatment or recent cessation (\< 3 mo) of hormone replacement therapy.
• •* Moderate or severe peripheral artery disease (ankle-brachial index \<0.7)(183)
• •* A graded exercise test will be performed by all subjects, if there is physician concern or an adverse event, the subject will not participate in a maximal oxygen consumption test (this will be determined in accordance with stated contraindications for exercise testing provided by the American Heart Association)(217)
• •* Claustrophobia, metal implants, etc., affecting feasibility and/or safety of the fMRI scanning.