Behind the commonly used term Rhubarb, there are actually about thirty species of perennial herbaceous plants, all belonging to the Polygonaceae family. Native to Southwest Asia, this plant is known for its digestive properties.
In the booming food supplement sector, rhubarb occupies a sometimes controversial place. Between benefits and contraindications, this plant is the subject of debate.
Let’s try to untangle the real from the fake.
The barbarian root
Coming from the lower Latin rheubarbarum or rhabarbarum, the sweet literary translation of the Rhubarb is indeed « barbarian root ». Historically, it was in Antiquity that the notoriety of certain species was felt. Rheum officinale was first used in China in 2700 BC as a medicinal plant for its digestive properties. Then in ancient Greece, used by Dioscorides, doctor, pharmacologist and botanist esteemed for his work. A book renowned for the major knowledge they bring to plant remedies.
How to recognize it?
Rhubarb is a vigorous and perennial plant. Aesthetically, it can be recognized by its large, stalked leaves and prominent, reddish veins. Be careful, these embossed, roughly triangular leaves are toxic due to the presence of oxalic acid and oxalate crystals. On the other hand, we consume petioles, the fleshy part that connects the leaf to the stem. Rounded, canaliculate, reddish green in colour, the petiole can reach up to 50 cm in length and 7 cm in width.
Where does it take root?
It is found in temperate regions, particularly in Belgium or in northern France where it is very widespread. Being a perennial plant, it survives the winter. But how does she do it? Thanks to a short voluminous rhizome, i. e. an underground stem loaded with food reserves. During winter, the aerial parts of the plant disappear while the rhizomes resist underground. Globally, Rhubarb can be cultivated anywhere as long as it has a soil rich in fresh and deep humus, all with an unburned sun or a soft shade. With all these elements, it will be ready to be harvested between April and September.
Rhubarb as a complement
Initially integrated into delicious cooking recipes, declined in compote, jam, pie… Rhubarb is now at the forefront of the food supplement scene.
In phytotherapy, the root of the species called Chinese rhubarb (Rheum officinale) is used, to distinguish it from the food Rhubarb with red-green tails.
Rhubarb roots, rich in fibre, have a laxative effect and act on the functioning of intestinal transit. They promote the activation of intestinal muscles for better intestinal comfort and more regular transit. This plant also has antioxidant properties, which when consumed, help to support digestion and purification of the body.
Emodine, present in the roots, makes Rhubarb an effective remedy for mild inflammation. For example, it is recommended to treat cases of oral diseases (mouth ulcers, gingivitis,…).
The main benefits of Rhubarb are derived from the components extracted from their rhizomes, and roots:
– Anthraquinone heterosides (60 to 80%)
– Dianthronic heterosides (10 to 25%)
– Gallic tannins (5 to 10%)
– Oxalic acid
The petiole of the rhubarb is edible, it contains soluble and insoluble fibres as well as organic acids. There is a low presence of vitamin C.
The Rhubarb presumed guilty
Do stimulating laxative plants always have their place in food supplements ?
Recently, the use of rhubarb in food supplements has been the subject of debate. The warning signal is given to the active ingredients called « hydroxyanthracene heterosides » present in so-called « stimulating » laxative plants. Their consumption implies a modification of intestinal hydroelectrolytic exchanges, a hydration of the stools and an acceleration of the transit. Rhubarb is not the only one to be pointed out, the plants consumed as food supplements containing these main active ingredients are: bourdaine, cascara, aloe juice and senna. The Academy of Pharmacy asks that these plants be deleted from the list of plants authorised in food supplements. This list was drawn up on 24 June 2014 by government decree.
Allegations in talks
To regulate and regulate the use of terminology in communication related to food supplements, there are nutrition and health claims. The list of allegations is first screened by Efsa before being validated by the European Commission. However, there is a second directory, which includes the so-called « pending » allegations. Rhubarb is one of the laggards. In the meantime, claims are tolerated, leaving companies free to use them in the nutraceutical market.
The Rhubarb pleads innocence
The rhubarb case has not yet been studied by Efsa. In this context, it is not claimed that this plant has any health benefits. Nevertheless, the subject should be treated with caution. Rhubarb, originally, is used in a traditional way for the design of remedies.
Used for thousands of years, rhubarb intends to claim its qualities. For the time being, the fact that they have not been studied does not mean that their properties are ineffective. Don’t be too strict. Tenacious, will the plant persist among food supplements?