Fasting ENHANCE Pilot Study

Inclusion Criteria: Age ≥ 65 years; Body Mass Index (BMI > 25 kg/m2) Normal age-, gender-, and education-adjusted performance on TICS-M (Telephone Interview for Cognitive Status) Responds yes to questions 1 (memory worse), 2 (word finding difficulties) or 3 (planning/organization difficulties) on the Subjective Cognitive Decline Questionnaire Reports onset of cognitive difficulties in past five years Reports they believe they are worse than others their age OR they have talked to a clinician about it. Provides informed consent and willing to be randomized to either intervention group. Exclusion Criteria: Failure to provide informed consent; Recent History or clinical manifestation of cardiovascular disease, diabetes, cholelithiasis, liver or renal disease, cancer, or progressive, degenerative neurologic disease (e.g., Parkinson's Disease, multiple sclerosis, ALS) Abnormal laboratory markers (e.g., renal or liver abnormalities, elevated potassium levels, or hemoglobin and hematocrit below the lower limit of normal) as determined by study physician. Significant cognitive impairment, defined as a scores below the cutoff for dementia on TICS-M Severe rheumatologic or orthopedic diseases (e.g., awaiting joint replacement, active inflammatory disease); Terminal illness with life expectancy less than 12 months, as determined by a physician; Other significant co-morbid disease (e.g. renal failure on hemodialysis) or severe psychiatric disorder (e.g. bipolar, schizophrenia); Current use of anabolic medications (i.e., growth hormones or testosterone), antidepressant medications, antipsychotic agents, monoamine oxidase inhibitors, anticholinesterase inhibitors (i.e., Aricept), anticoagulant therapies (aspirin use is permitted), or antibiotics; Excessive alcohol use (>14 drinks per week); History of drug or alcohol abuse (i.e., more than 5 drinks/day for males or more than 4 drinks/day for females); Planning to permanently leave the area in the next year; History of pulmonary disease, pneumonitis or interstitial lung disease; Current smoker or less than 3 years quit; Creatinine clearance < 30 ml/minute by estimated Glomerular Filtration Rate (eGFR); Fasting >12 hours per day Actively trying to lose weight by participating in formal weight loss program or significantly restricting calorie intake or weight loss > 5 lbs in the past month Resting heart rate of >120 beats per minute, systolic blood pressure > 180 mmHg or diastolic blood pressure of > 100 mmHg Unstable angina, heart attack or stroke in the past 3 months Continuous use of supplemental oxygen to manage a chronic pulmonary condition or heart failure Rheumatoid arthritis, Parkinson's disease or currently on dialysis Insulin dependent diabetes mellitus Taking medications that preclude fasting for 16 hours (e.g. must be taken with food at least 12 hours apart) Participating in another clinical trial or has received an investigational product within 30 days prior to screening/enrollment Any condition that in the opinion of the investigator would impair ability to participate in the trial.