Beyond weight loss: current perspectives on the impact of calorie restriction on healthspan and lifespan

ABSTRACT

Introduction: Changes to mental, physical, and physiological functions drive the complex processes underlying the variable progression of human aging. Nutritional interventions are one of the most promising non-pharmacological therapeutics to attenuate aging in humans. This narrative review aims to describe the implications of moderate and prolonged calorie restriction (CR) in healthy adults without obesity that occur beyond weight loss.

Areas covered: Findings from CR studies, such as the CALERIE (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy) trials, the most rigorous trials to date examining a prolonged 25% CR, are described. The main areas covered include; changes to anthropometrics, energy metabolism, cardiometabolic health, inflammation and immune function, physical fitness, health behaviors, and mental health in response to weight loss (1-year) and weight loss maintenance (2-year).

Expert opinion: CR presents a novel and effective therapeutic approach for improving healthspan and biomarkers of lifespan. To date, scientific evidence suggests that continued CR, under medical supervision, is accompanied with persistent and beneficial effects on health outcomes independent of weight loss. Mechanisms are yet to be fully elucidated, and novel dietary approaches that may similarly attenuate aging-related conditions should be explored and compared to traditional CR.

KEYWORDS:

• Caloric restriction
• cardiovascular diseases
• energy metabolism
• health behavior
• inflammation
• longevity
• mental health
• physical fitness
• weight loss

Article highlights

• Calorie restriction (CR) is an effective dietary intervention to promote healthspan and biomarkers of lifespan.

• Moderate CR results in beneficial changes to adiposity, energy metabolism, oxidative stress, blood pressure and lipid profile, glycemic markers, the inflammatory milieu, growth factors, physical fitness, eating behaviors, psychological measures of general health, sexual drive, and sexual relationship.

• CR is not approved as a self-administered therapeutic and should be implemented under direct medical supervision and as part of a multidisciplinary healthcare approach.

• Sustaining moderate CR can be difficult. Novel dietary approaches that may equally or more practically mimic the health benefits of CR are needed and imminent.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This work was supported in part by National Institutes of Health grants (R01DK124806 and R01NR017644).