Over the past few decades, the role of nutrition as a vital element of health has gained significant recognition. Both the quality and quantity of dietary intake play a pivotal role in preventing age-associated diseases, such as cardiovascular conditions, neurodegenerative disorders, metabolic syndromes, and cancer. Adequate nutrition can improve the condition of cancer patients, who are often malnourished, by enhancing their response to anti-tumor therapies and reducing drug side effects, thereby improving their quality of life. Calorie restriction and periodic fasting have recently been the focus of extensive preclinical research due to their potential to extend lifespan and enhance the efficacy of anti-tumor therapies in mouse models. These dietary interventions have garnered significant attention on social media and in the media, gaining public support despite the lack of clinical validation.
In this review, we examine clinical studies on dietary restriction within the contexts of oncology and longevity, with the aim of clarifying the concrete advantages these interventions may offer. As anticipated in our previous analyses, the results of clinical studies have been disappointing, as these interventions fail to provide significant benefits. This highlights the challenges associated with translating successful outcomes from animal models to human applications. However, the promotion of these dietary interventions in the mass media and on social media continues to spread alleged benefits that are not supported by clinical data.