How to Lose Fat & Gain Muscle With Nutrition | Alan Aragon

In this evidence-based presentation, renowned nutrition researcher Alan Aragon delves into the key dietary principles for simultaneously losing body fat and building lean muscle. Grounded in peer-reviewed studies and his own meta-analyses, Aragon begins by framing energy balance—calories in versus calories out—as the primary driver of fat loss. He explains how a modest calorie deficit of roughly 10–20 percent below maintenance levels typically yields steady fat reduction while preserving performance and muscle tissue. Aragon emphasizes gradual adjustment of intake to prevent excessive metabolic slowdown or strength loss. The video then shifts to macronutrient distribution, highlighting protein as the most important macro for body recomposition. Aragon recommends 1.8 to 2.7 grams of protein per kilogram of body weight, citing research that higher protein intakes support muscle synthesis, improve satiety, and reduce lean mass loss during dieting. He also covers carbohydrate and fat targets, suggesting flexible ranges—25–40 percent of calories from fat and the balance from carbohydrates—tailored to individual preferences and activity levels. This flexible dieting approach prioritizes adherence and nutritional quality over rigid meal plans. Nutrient timing is addressed next, though Aragon cautions against overemphasizing exact meal windows. He notes that total daily intake remains paramount, but recommends distributing protein evenly across three to six meals to maintain amino acid availability. Pre- and post-workout nutrition are discussed briefly: consuming both protein and carbohydrates around training can modestly enhance recovery, but Aragon asserts that their impact is small relative to total intake. Beyond diet composition, the presenter underscores the vital role of resistance training and progressive overload in stimulating muscle growth. He reviews studies demonstrating that combining strength training with high-protein diets facilitates recomposition more effectively than either strategy alone. Additionally, he dispels myths around excessive cardio, noting that too much can impede muscle gains and increase recovery demands. A moderate approach—two to four cardio sessions per week—is recommended for cardiovascular health without undermining strength progress. Throughout the talk, Aragon integrates practical tips for real-world application: track your intake using reliable tools, adjust calories gradually based on weekly weight trends, and prioritize whole, nutrient-dense foods over ultraprocessed options. He closes by reminding viewers that consistency, patience, and evidence-based adjustments are the keys to long-term success in losing fat and gaining muscle.