Determining the optimal daily intake of leucine is crucial for individuals seeking to maximise muscle protein synthesis and overall health. Leucine, an essential amino acid, plays a pivotal role in stimulating protein synthesis, making it particularly important for those engaged in regular exercise or aiming to maintain muscle mass[1].
To stimulate muscle growth, your body needs approximately 1,700–3,000 milligrams (mg) of leucine at any given time. This translates to 15-25 grams of whey protein powder[1].
However, individual needs may vary based on factors such as age[2], weight, level of physical activity, and overall dietary protein intake. Athletes or those engaged in intense resistance training may require higher leucine intake to support muscle repair and growth.
Foods rich in leucine include animal-based proteins such as meat, poultry, fish, eggs[3], and dairy products, as well as plant-based sources like legumes, nuts, seeds[4], and soy products. For those struggling to meet their leucine requirements through diet alone, supplementation may be considered under the guidance of a healthcare professional or registered dietitian.
It is important to note that while leucine plays a vital role in muscle protein synthesis[5], consuming excessive amounts beyond what is necessary may not provide additional benefits and could potentially lead to adverse effects. Therefore, focusing on a balanced diet that includes adequate protein and spreads leucine intake evenly throughout the day is key to optimising muscle health and overall well-being.