Intermittent Fasting (IF), a dietary modification through time-restricted feeding, has gained significant attention in the past few years owing to its advantages in metabolic health and weight management. Available evidence suggests that IF can improve insulin sensitivity; lower the levels of blood glucose and fat; prevent body fat accumulation; and reduce the risk of obesity-related chronic disease by mitigating oxidative damage and affecting the activity of antioxidant enzymes. However, a number of gaps in knowledge remain regarding IF, especially its long-term safety and the generalisability of IF. This paper discussed the effects of IF on metabolism and body health through the mechanism of high-intensity, nutrient-strong IF. It mentioned that IF led to improved insulin sensitivity, lower blood lipid levels and inhibition of body fat accumulation, and was easier to stick to than daily calorie restriction. Other clinical studies with longer intervals and durations also reported significant effects of IF on weight loss and body health. Long term strict IF is unfavorable for some patients – in particular the elderly and the chronically ill – due to the potential for nutritional and metabolic problems. This study serves as an important reference for the use of IF in health and weight loss management, and offers potential directions for future research. Even though IF showed clear benefits, its safety in the long term and applicability across different populations still need to be validated. Future investigations may look into the long-term effects of IF in different populations, and its potential application in various health conditions.