Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by the onset of symptoms, typically occurring later in life, and significant deficits in cognitive functions including learning, memory, speech, and behavior. Ongoing research endeavors seek to explore methods for preventing and treating AD, as well as delving into the molecular mechanisms underlying existing and novel therapeutic approaches encompassing exercise, diet, and drug regimens for individuals with AD or those at risk of developing AD. Among these interventions, dietary interventions have garnered increasing attention due to their potential in addressing the disease. Eating is among the most fundamental of human daily activities, and controlled dietary practices, such as fasting, have gained prominence as essential clinical methods for disease prevention and treatment. Research findings indicate that fasting holds promise in effectively alleviating and improving the cognitive decline associated with age or as consequence of disease. The clinical efficacy of fasting in addressing AD and related disorders might be grounded in its influence on various molecular mechanisms, including neuroinflammation, glial cell activation, insulin resistance, autophagy regulation, nerve regeneration, the gut microbiome, and accumulations of amyloid-\beta and tau proteins. The present study reviews possible molecular mechanisms underpinning the therapeutic effects of fasting in patients with AD, as well as in models of the disorder, to establish a theoretical basis for using fasting as a viable approach to treat AD.