Protein shakes for teenagers: Good or bad idea?

You can take it as a powdered drink, or in a snack bar. Puddings and certain breads are also promoted as "sources of protein," and protein-enriched products like Kindershake and Teen Balance are specifically designed to appeal to a young people — and it appears to be working.

In a representative survey of almost 1,000 parents by the University of Michigan in 2024, just under half said their children, who were aged 13 to 17, had consumed protein products over the previous year. The survey found that boys were more likely to do so than girls, especially in connection with sport, or to build muscle. Girls took them to balance their diet, and to lose weight.

According to the statistics portal Statista, between March 2024 and March 2025 the fitness protein product market in Germany recorded a huge jump of around 25% in retail revenue.

Proteins are key building blocks for our metabolism. They play an important role in building up and repairing tissue in our muscles, skin and organs. Proteins are the basis for the formation of enzymes that regulate chemical reactions in the body, and of antibodies that are vital for our immune system.

According to the German Nutrition Society (DGE), healthy adults should consume 0.8 grams of protein daily per kilogram of body weight. A woman weighing 65 kilos should eat 52 grams of protein per day, for example.

But they can do this without special protein products. A portion of oat flakes with an almond drink for breakfast, a baked potato with curd cheese for lunch, and two slices of wholemeal bread with peanut butter in the evening — objective achieved.

Young people should consume a little more, as they are still growing. For them, the formula is 0.9 grams of protein per kilo of body weight. A teenager weighing 45 kilos should therefore eat 40.5 grams of protein per day. People over 65 and children aged one to four should have a little more: one gram of protein per kilo of body weight.

Older people tend to eat too little protein, often because their appetite decreases. But a study done in Germany between 2015 and 2017 showed that children and young people there often consume too much. Around half of six- to 17-year-olds ate more than double the recommended daily amount of protein.

Too much protein can be harmful in the long term, according to the DGE. Various studies show that children who eat too much protein, particularly animal protein, often become overweight. Some enter puberty early.

Above all, too much protein can put excessive strain on the kidneys, causing damage. The kidneys have to convert the amino acids that constitute the building blocks of proteins into urea before they are excreted in urine. Damage is particularly likely if a person doesn't drink enough fluids, or has pre-existing kidney damage — but adolescents are also at greater risk.

A person's protein requirement is greater if they are very physically active. Among other things, according to a DGE position paper, proteins can help maintain or build up muscular mass and strength, and support recovery after strain.

The paper states that, depending on physical condition and what they are training for, sportspeople should consume between 1.2 and 2 grams of protein per kilo of body weight, divided into several portions throughout the day. These recommendations only apply to people who train for more than five hours a day.

Proteins are of interest to people who want to lose weight because they are good at satisfying hunger. People usually lose more weight by following a protein-rich diet rather than another. Long-term, though, the most important thing to look at is: How many calories am I consuming, and how many am I burning?

Overall, plant proteins usually contain somewhat fewer essential amino acids than animal protein. "Essential" because the body cannot make them by itself – it has to take them in as food.

However, wholegrain products, pulses, or nuts are also higher in fiber, vitamins, and unsaturated fats – all of which are healthy. The DGE therefore advises that protein intake should be increased primarily with sources of plant protein.

Protein powders and bars are often enriched not only with vitamins and minerals but also with unhelpful ingredients like sweeteners, sugar, additives and flavorings. The German Sport University in Cologne even found doping substances in protein products that were praised for building muscle.

Adolescents in particular might experience an unpleasant side-effect of consuming protein powders. These usually consist of milk proteins. There are various ways in which milk proteins can increase the skin's production of sebum, and this can trigger or exacerbate acne, although a direct link between milk protein products and acne has not been definitively proven.

Specialists are also skeptical about protein shakes, fearing that they could lead to young people eating fewer normal meals, and thus consuming less fiber, micronutrients, and healthy fats.

Protein-enriched foods are usually expensive. In a 2022 study, consumer organizations also found that foods that are naturally high in protein, such as cheese, curds, or soya drinks, often cost more if the protein content has been highlighted by the manufacturer.

Not even sportspeople with a high protein requirement need to supplement their diet with special protein products. The DGE advises that they should aim to satisfy their requirements by optimizing their diet, and says there is no scientific evidence that our bodies require protein-enriched food supplements when put under strain.

However, the experts do say that it may make sense for people to use protein preparations if they have allergies, problems with digestion, chewing, or swallowing, or if their appetite is very low.

This article has been translated from German.