Protein, algae as an alternative to meat to build muscles?

Seaweed can represent a valid alternative to meat as source of protein to maintain and build muscle mass? We know that a protein-rich diet has “better” muscle health, but no differences emerged in relation to the type of plant or animal protein. If it is true that all proteins contain essential amino acids (i.e. not synthesizable by our organism and therefore to be introduced with food), fundamental for producing energy and guaranteeing neuromuscular activity, it is also true that in vegetable ones The amino acids I definitely am less concentrated. This means that vegetable proteins must be taken in greater quantities: in synthesis those who follow a vegetarian diet need to eat a little more because plant proteins are generally less absorbed by the blood. However, very little is known about algae and a group of scientists from the University of Exeter, in England, tried to investigate the topic with a study published in The Journal of Nutrition.

Spirulina and chlorella

Their findings suggest that algae, if grown under controlled conditions, could represent an interesting and sustainable alternative to animal-derived proteins to build and maintain muscle mass. The researchers studied in particular the spirulina and the chlorellathe two most commercially available algae (they lend themselves to being pulverized and therefore can be proposed as supplements), particularly rich not only in proteins but also in essential amino acids and lipids, mono- and polysaturated fatty acids and vitamins.

Animal proteins: ethical and environmental problems

Animal protein sources are known to effectively stimulate resting and post-exercise muscle protein synthesis. However, the production of proteins of animal origin is associated with increasing ethical and environmental concernsso the researchers wondered whether algae could represent a viable alternative. Since it was not yet very clear whether spirulina and chlorella had the ability to stimulate protein synthesis in humans Scientists worked to fill this gap by evaluating the impact of ingesting spirulina and chlorella compared to a high-quality, non-animal dietary protein source (mycoprotein of fungal origin) on the concentration of amino acids in the blood at rest and after exercise to assess muscle protein synthesis rates.

The study: amino acids and protein synthesis in algae

36 young adults participated in the study (randomized and double-blind) who, after an exercise on a single leg, ingested a drink with 25 grams of proteins of fungal origin, or from spirulina, or from chlorella. Blood and muscle samples from the volunteers were analyzed before and after exercise, and amino acid concentrations in the blood and rates of muscle protein synthesis in the tissues at rest and post-exercise were evaluated. Protein ingestion has increased amino acid concentrations in the bloodbut more quickly and with higher response peaks after spirulina consumption. Between the three groups there are no differences regarding muscle protein synthesis rates, which however were higher in muscles after exercise compared to those at rest. «Spirulina and chlorella – comments Stefano Erzegovesi, medical nutritionist and psychiatrist – are two excellent protein sources: just think that from 50 to 70% of their dry weight are proteins and are also very well balanced in terms of content of essential amino acids, despite are of vegetal origin.”

Costs and sustainability

The cost of spirulina and chlorella is also interesting: the product is also sold online as a supplement at around 20 euros for 300 grams of powdered dry algae. «This means 2 euros for 15 grams of good quality and sustainable protein in terms of CO2 emissions, a price that competes well with animal protein sources» adds Erzegovesi.

Safe and sustainable food future?

Researcher Ino Van Der Heijden of the University of Exeter, one of the authors of the research, commented: «Our work has shown that algae could become part of a safe and sustainable food future. With more and more people trying to eat less meat for ethical and environmental reasons, there is growing interest in non-animal-derived and sustainably produced proteins. We believe it is important and necessary to start examining these alternatives and we have identified algae as a new and promising source of protein.”

The dosage limit

So everything is fine? In reality we shouldn't imagine a nice plate of seaweed salad because, as Stefano Erzegovesi points out, the real limit is the dosage: «This makes the algae that are not very usable as daily food and, at most, they can be used as supplement. In fact, to take 25 grams of product per meal we would have to swallow 50 tablets at a time, something unsustainable for our stomach. The alternative could be to take algae as a powdered supplement in a smoothie, as Hollywood stars do, but, thinking of the average palate of the Italian population, not accustomed to the taste of algae, it becomes difficult to savor and digest if taken every day ».

It is not a vitamin B12 supplement

Finally, the nutritionist warns against the incorrect use of algae: «Spirulina and chlorella are often passed off as vitamin B12 supplements, which is essential for vegans. The problem is that the B12 they contain is a non-absorbable analogue: therefore not only is it not usable by the body, but it can also compete with the “good” B12 in terms of absorption sites.”

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