Safety of Bioactive Collagen Peptides

Manufactured Bioactive Collagen Peptides are generally recognized as safe, as long as they are derived from food. Such peptides also result from digestion within our body or during cheese fermentation. So far, no adverse effects have been described in association with Bioactive Collagen Peptides [Hettiarachchy (Ed.) 2012]. Comprehensive studies with hypoallergenic infant food or other diet products containing hydrolysed proteins have not given rise to any safety concerns [Schaafsma 2009]. Gelatine, which is often used as starting material for the production of Bioactive Collagen Peptides, has been part of our diet for a long time. Toxicity studies have not shown any safety problems, as long as the manufacturing conditions were compliant with current food regulations [Hettiarachchy (Ed.) 2012].

In a double-blind randomized study, Kumar et al. investigated the impact of Bioactive Collagen Peptides on key blood values of liver and kidney function, and blood sugar levels. There was no evidence of altered values when theses peptides were given at a concentration of 10 g per day for 13 weeks [Kumar et al. 2015]. Likewise, no changes were found in a 12-month study using 5 g Bioactive Collagen Peptides [König et al. 2018]. Another study with 15 g Bioactive Collagen Peptides for more than 3 months found no evidence of adverse effects as well [Zdzieblik 2015]. Nevertheless, further long-term studies are warranted to assess the safety of long-term use.
In 2012, the European Food Safety Authority (EFSA) (Ex. Link EFSA) published its opinion on protein needs of healthy individuals, including the potential risks of protein-rich diets [EFSA 2012]. Protein requirements of a healthy adult were estimated at 0.83 g/kg of body weight. Exceeding this value by more than twice the amount was still considered safe.

Protein Needs

Protein needs of a healthy adult are based on the so-called nitrogen balance of the body. It is assumed that the body has to ingest the amount of protein equivalent to the amount of nitrogen that is excreted by the body. The average protein requirements were estimated at 0.66 g/kg of body weight/day (based on normal body weight). Assuming that the body cannot use 100% of the ingested protein, and taking into account differences within the population, 0.83 g protein per kg of body weight per day has been set as a fixed value [EFSA 2012]. This estimate is valid for healthy adults in good condition and with normal activity levels. Other values apply to children, pregnant women, and nursing mothers.

Proteins have many functions in the body. They act as enzymes promoting key metabolic turnover, they serve as transporters (e.g., hemoglobin in the blood), and they provide crucial immune molecules, hormones, and neurotransmitters. Our body could not survive without an adequate protein intake [Berdanier 2015]. However, the actual protein needs of an individual are influenced by a variety of factors. Heat or cold, for example, increase basic energy and protein requirements. In addition, physical activity increases protein needs, as do infections or injuries that lead to enhanced protein synthesis in the body [Berdanier 2015].

However, the determination of nitrogen balance also has its drawbacks. Nitrogen losses caused by sweating, for example, or hair and nail growth are not taken into account. Moreover, the biological value of proteins is not considered [Berdanier 2015]. It also remains unclear whether protein needs are directly proportional to the body weight [Hoffer 2016].

Therefore, further methods, like the indicator amino acid oxidation (IAAO) method, have been developed to determine the protein needs of the body. Notably, this method results in higher values of protein needs compared to other methods [Pencharz et al. 2016, Phillips et al. 2016, Phillips 2017].

However, we should always consider that all of these estimations are based on theoretical considerations and can only provide average values. The optimal amount of protein for any one individual can differ from the average value. In addition, the calculated protein needs is not an absolute value and other food ingredients (e.g., fat, carbohydrates, vitamins, etc.) also have to be considered. If fat intake is reduced below 20 to 30% of the energy needs, proteins are used for energy production instead of product synthesis [Berdanier 2015]. In my opinion, there is no need to calculate the diet down to the very last detail as long as a person is healthy and fit and has a reasonable diet. Under these conditions, the person couldn’t have done that much wrong.

The Biological Value of Protein

The so-called biological value describes the degree to which the human body can digest and use protein. The amino acid composition and the amount of essential amino acids are also captured. The biological value of proteins from animal sources (meat, fish, dairy products, eggs) is higher than that from vegetable sources, since vegetables lack certain amino acids [Berdanier 2015]. However, this deficiency can be compensated for by a combination of several plant proteins. Soy protein, for example, has only a low methionine content, which can be balanced by combining soy protein with maize.

Although collagen and collagen hydrolysates are highly digestible, their biological value is often described as low due to their lack of tryptophan. However, collagen or collagen hydrolysates are rich in glycine and proline, and are a good source of arginine. From the point of view of nutrition physiology, they are thus considered useful as additional protein source. They are also helpful for the supplementation of amino acids, which may have become essential due to a disease as well as non-specific nitrogen compounds [Castellanos et al. 2006].

The assessment of protein requirement on the basis of nitrogen balance alone is insufficient, as it does not adequately consider the changing demands of the body for individual amino acids and their excretion. Amino acids are not only required to build proteins, but also play an important role in metabolic processes and regulatory loops. Since amino acids cannot be stored by the body, needs must be met by either the food ingested or the degradation of body protein. In addition, the body’s own production of non-essential amino acids may not be sufficient in some circumstances. Dunstan et al. investigated the balance of the individual amino acids in men and women in a model calculation. A typical Western mixed diet based on animal and vegetable protein was applied [Dunstan et al 2019]. The authors could show that a certain lack of histidine, glycine, serine, and ornithine was possible despite a positive nitrogen balance, especially during heavy physical stress.

The influence of a replacement of protein by collagen peptides on the biological value of nutrition was investigated by Paul and coworkers. The authors calculated the value of Western food according to the PDCAAS method [Paul et al 2019]. According to the study, up to 36% of protein intake can be replaced by collagen peptides without affecting the intake of high quality protein (PDCAAS equals 1.0). Even ingesting the recommended doses of 2.5 g to 15 g collagen peptides per day does not counteract the recommended protein intake of 0.83 g protein per kilogram body weight.

Although collagen hydrolysates are unsuitable to cover the entire protein requirement of the body, they offer a good way to supplement important amino acids. Replacing a portion of proteins by collagen peptides in recommended doses does not impair the quality of protein intake, provided that a standard Western mixed diet is met. Since an increased protein intake may be advisable, especially in old age, during exercise, or under other circumstances [Phillips et al 2016],  there is no reason for refraining from collagen peptides as a protein source in addition to the officially recommended amounts of protein [Paul et al 2019].

Last update: September, 2022