We analyzed the available evidence on whether 2 grams of leucine reduces hunger when taken with a low-protein meal, and what we’ve found so far leans toward a reduction in hunger. All 74 assertions reviewed support this idea, with no evidence suggesting the opposite. The data indicates that adding 2 grams of leucine to a meal low in protein may help lower feelings of hunger compared to not taking leucine at all. Additionally, the evidence suggests that increasing the dose up to 2 grams appears to strengthen this effect, meaning more leucine in this range may lead to greater hunger reduction. Leucine is one of the branched-chain amino acids found in protein-rich foods like meat, eggs, and dairy. It’s thought to play a role in signaling fullness to the brain, though the exact mechanism isn’t fully understood. In this context, the evidence we’ve reviewed focuses on its use as a supplement added to meals that don’t contain much protein — such as a snack or light meal — and whether that helps people feel less hungry afterward. We note that all the evidence comes from assertions, not controlled human trials, and we have no details on study design, participant numbers, or duration. This means we can’t say how strong or consistent this effect might be across different people or situations. Still, the pattern we see is consistent: more leucine, up to 2 grams, seems linked to less hunger in low-protein meals. If you’re eating a light, low-protein meal and feel hungry soon after, adding 2 grams of leucine might help — but it’s not a substitute for balanced nutrition.