Short-term time-restricted feeding is safe and feasible in non-obese healthy midlife and older adults.

Chronic calorie restriction (CR) improves cardiovascular function and several other physiological markers of healthspan. However, CR is impractical in non-obese older humans due to potential loss of lean mass and bone density, poor adherence, and risk of malnutrition. Time-restricted feeding (TRF), which limits the daily feeding period without requiring a reduction in calorie intake, may be a promising alternative healthspan-extending strategy for midlife and older adults; however, there is limited evidence for its feasibility and efficacy in humans.

Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD in healthy middle-aged and older adults.

Nicotinamide adenine dinucleotide (NAD) has emerged as a critical co-substrate for enzymes involved in the beneficial effects of regular calorie restriction on healthspan. As such, the use of NAD precursors to augment NAD bioavailability has been proposed as a strategy for improving cardiovascular and other physiological functions with aging in humans. Here we provide the evidence in a 2 × 6-week randomized, double-blind, placebo-controlled, crossover clinical trial that chronic supplementation with the NAD precursor vitamin, nicotinamide riboside (NR), is well tolerated and effectively stimulates NAD metabolism in healthy middle-aged and older adults.