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Is it necessary to take amino acid supplements? Here’s who can really benefit from them

The team of doctors and fact-checking experts from the National Medical Association addresses the main health-related concerns

23 October 2026

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4' min read

Translated by AI

Versione italiana

4' min read

Translated by AI

Versione italiana

Powders, capsules, vials: amino acid supplements are often marketed as a valuable aid for muscle development, post-workout recovery or staying fit as we get older. But are they really necessary? Most people do not need to take supplements: amino acids are the building blocks of proteins and are already found in the food we eat every day as part of a balanced diet. Let’s take a closer look at them…

What are amino acids and where can we find them?

Amino acids are the building blocks the body uses to build proteins, including those in the muscles. There are twenty amino acids that make up proteins: nine are known as ‘essential’ because the body cannot produce them in sufficient quantities and they must be obtained from food. Muscle proteins are constantly being renewed: old ones are broken down and replaced by new ones. To build new ones, all amino acids – including the essential ones – are needed in adequate quantities. Three of these – leucine, isoleucine and valine – are known as BCAAs (‘branched-chain amino acids’), and a large market for supplements has developed around them. But where are amino acids found? In the proteins of food. Those of animal origin (meat, fish, eggs, milk and dairy products) contain all the essential amino acids. Those of plant origin are less complete, but combining them – for example, by pairing pulses and cereals in a single dish – compensates for this deficiency. Soya contains proteins of a nutritional quality equivalent to those of animal origin.

How much protein should I eat every day?

For an adult, between 0.83 and 0.90 grams of protein per kilogram of body weight per day is recommended. The lowest figure, 0.83, is that of the European Food Safety Authority (EFSA); the highest, 0.90, is that of the Italian Society of Human Nutrition for adults up to the age of 59. For a person weighing 70 kilos, that works out at around 58–63 grams per day.

After the age of 60, the guidelines change. The LARN (Reference Intake Levels for Nutrients and Energy for the Italian Population) set a target of 1.1 grams per kilogram per day, whilst the European guidelines on clinical nutrition recommend ensuring at least 1 gram per kilogram, tailored to the individual.

According to the EFSA, the average amount of protein consumed by adults in Europe is often equal to or greater than the recommended amount.

But is eating a lot of protein bad for your kidneys?

In people with normal kidney function, there is no strong evidence that a high protein intake causes kidney damage in the short to medium term; however, there is a lack of robust data on the very long term. In cases of chronic kidney disease, on the other hand, protein intake should be tailored to the individual.

If I do sport or want to build muscle, are supplements necessary?

A study that pooled the results of numerous research studies on healthy adults compared two groups of people following the same weight-training programme: one group added protein to their daily diet, whilst the other did not. The added protein often came from supplements, and in some cases from milk, yoghurt or meat. In the group that had added protein, strength and muscle mass increased slightly more, but the figures indicate only a modest average benefit. For muscle mass, beyond approximately 1.6 grams of protein per kilogram of body weight per day – including protein from food – there appears to be no further benefit on average. Please note: the study concerns protein as a whole, not individual amino acids taken on their own.

For individual amino acids (BCAAs), the situation is different. In 2010, the EFSA reviewed the evidence presented in support of various benefits attributed to BCAAs, ranging from muscle growth to recovery after exercise, from perceived fatigue to mental performance after exercise and to immune defence, and found that no effect had been demonstrated for any of them. With regard to muscle, in particular, BCAAs have not been shown to have any additional effect beyond that already known for protein.

For elite athletes, a 2018 consensus document from the International Olympic Committee considers the contribution of supplements to nutrition to be minor, although some may be beneficial. We also discussed this in the factsheet “Do athletes need supplements?”.

And what about older people?

In healthy older people, protein supplements are not routinely necessary; however, they may be helpful in certain medical conditions.

A study that pooled the results of numerous systematic reviews assessed the effect of protein supplements added to the diet. In healthy older adults, it found no increase in muscle mass, strength or physical performance. In older people with chronic conditions, however, it did find small increases in muscle mass and strength, with stronger evidence when combined with physical exercise. In those hospitalised for a hip fracture, it found fewer medical complications. The authors caution, however, that the underlying research is limited and that the reviews are often of poor quality.

We have also discussed muscles that weaken with age in the fact sheet “Is muscle loss a problem for all older people?”. If you suspect you are losing muscle mass, it is therefore advisable to discuss this with your GP, who will be able to assess the type of support required on a case-by-case basis.

Read the full article on the dottoremaeveroche website, run by Fnomceo