Intermittent fasting and lipid metabolism: Mechanisms, clinical evidence, and therapeutic implications

Intermittent fasting (IF) is a way of eating that can help the body burn fat more efficiently and lower the risk of heart disease. It leads to helpful changes in blood composition and in metabolism. Still, there are questions about how safe, practical, and effective IF is over the long term. Because of these unknowns, it is important to have clear guidelines for IF and to continue research in this area. Background & Aim: Common IF methods include alternate-day fasting (ADF), the 5:2 diet, time-restricted eating (TRE), and Ramadan fasting (RF). This review points out that we still do not fully understand how IF works in the body and highlights areas that need more study. The main aim is to show how dietary approaches can help manage metabolic diseases and support health, either on their own or alongside other treatments. Summary: IF consistently improves lipid profiles, insulin sensitivity, body weight, and indirectly, due to the above cardiometabolic risk factors in people with obesity, metabolic syndrome (MeS), and type 2 diabetes (T2D). However, its effects on high-density lipoprotein cholesterol (HDL-C) are mixed. When compared directly to continuous energy restriction (CER) with concomitant energy deficits, both approaches are similarly effective for improving lipid and weight outcomes. IF may provide additional benefits for short-term fat loss and adherence. Additionally, it may be a profitable alternative to or support of pharmacological therapy.