Supplements

Protein Powder (Whey & Casein)

Concentrated dairy or plant protein used to reach daily protein targets, covered by the ISSN position stand on protein and exercise.

Protein powders are concentrated protein extracted from milk (whey, casein), eggs or plants (soy, pea, rice). They are a food-format convenience: the research treats them as one way of reaching a daily protein target, not as a separate substance with unique effects.

What published research reports

The International Society of Sports Nutrition position stand on protein and exercise (2017) reports that exercising individuals benefit from overall daily protein intakes of 1.4–2.0 g per kg of body weight for building and maintaining muscle, delivered in doses of roughly 20–40 g spread across the day, and states that protein supplements are a practical way to meet those targets when whole foods are insufficient or inconvenient. It describes whey as a rapidly digested protein with high leucine content, and casein as a slower-digesting protein, with both able to support muscle protein synthesis; the document notes that total daily intake matters more than the specific source for most outcomes. It also reports that these intakes have not been shown to harm kidney or bone health in healthy, exercising people.