There is no scientific evidence to support the claim that whey protein can stunt growth. In fact, the opposite may be true. Consuming adequate amounts of protein, including whey protein, is important for proper growth and development. However, it is important to consume protein in moderation and to consume a balanced diet that includes a variety of food sources, not just whey protein. Overconsumption of any single nutrient can have negative effects on health. Consult with a doctor or a registered dietitian if you have concerns about your protein intake.