Are Protein Shakes a Smart Choice for Teenagers? What Nutrition Experts Say

Powdered drinks, snack bars, puddings and even certain breads are now marketed as sources of protein, and products such as Kindershake and Teen Balance are designed specifically to appeal to young people. The approach appears to be paying off.

A representative 2024 University of Michigan survey of almost 1,000 parents found that just under half said their children, aged 13 to 17, had consumed protein products in the previous year. Boys were more likely to use them than girls, typically for sport or to build muscle. Girls more often said they used them to balance their diet or to lose weight. Statista data shows the fitness protein product market in Germany grew by around 25% in retail revenue between March 2024 and March 2025.

Proteins are central to the body's metabolism. They help build and repair tissue in muscles, skin and organs, and they form the basis of enzymes and of the antibodies the immune system relies on. The German Nutrition Society (DGE) recommends that healthy adults eat 0.8 grams of protein per kilogram of body weight daily, which works out to 52 grams for a woman weighing 65 kilos. Teenagers, who are still growing, should aim for 0.9 grams per kilo, or 40.5 grams for a 45-kilo adolescent. People over 65 and children aged one to four need about one gram per kilo.

Ordinary food can easily meet those targets. Oat flakes with almond drink, a baked potato with curd cheese and wholemeal bread with peanut butter would be enough. In fact, a German study conducted between 2015 and 2017 found that about half of six- to 17-year-olds ate more than double the recommended amount.

The DGE warns that too much protein can cause harm over time. Studies suggest children who eat excessive protein, especially from animal sources, often become overweight, and some enter puberty early. The kidneys must convert amino acids into urea for excretion, so a heavy protein load can strain them. The risk is higher for people who drink too little or already have kidney damage, and adolescents are also more vulnerable.

Needs do rise with heavy physical activity. According to a DGE position paper, athletes should take in 1.2 to 2 grams per kilo of body weight, spread across several portions a day, though those recommendations apply only to people who train more than five hours daily. Protein can also help with weight loss because it satisfies hunger, although over the long term the balance of calories consumed and burned matters most.

On the question of sources, plant proteins generally contain somewhat fewer essential amino acids than animal proteins. However, wholegrains, pulses and nuts also supply fiber, vitamins and unsaturated fats, so the DGE advises raising protein intake mainly through plant sources.

Critics also point to the products themselves. Powders and bars are often loaded with sweeteners, sugar, additives and flavorings, and the German Sport University in Cologne found doping substances in some protein products promoted for muscle building. Because most powders are made from milk proteins, which can increase skin sebum production, they may worsen acne in teenagers, although a direct link has not been definitively proven. Specialists also worry that shakes could displace regular meals and the fiber, micronutrients and healthy fats they provide.

Cost is another factor. A 2022 consumer organization study found that naturally protein-rich foods such as cheese, curds and soya drinks often cost more when manufacturers highlight their protein content. The DGE says there is no scientific evidence that the body needs protein supplements under strain, even for athletes. Experts do see a possible role for protein preparations among people with allergies, digestive, chewing or swallowing problems, or very low appetite.