The Plant with Retinoid-Like Action

Crithmum Maritimum is a Halophytes plant (Marine plant) commonly-known as sea fennel or rock samphire, this wild, naturally salt-tolerant plant is usually found on maritime rocks, piers and sandy beaches along the Mediterranean, Black sea and European Atlantic coasts. It is rich in bio-available nutrients, found in the sandy soil, silica being one example, coupled with the nutrients courtesy of the ocean waters and airflow. Crithmum Maritimum has long been highly regarded for both its healing and medicinal purposes. 

The term Crithmum is derived from Greek krithe (barley), probably due to the resemblance of fruits, in the past, sea fennel was used in many ways:

  • In folk medicine to prevent scurvy and for vermifuge and diuretic effects.
  • In Spain, pickled leaves are eaten as a digestive and for its antiscorbutic and diuretic properties.
  • In Northern regions, the sea fennel decoction is used in folk medicine to take care of the urogenital apparatus and liver,
  • Southern Italy, the same decoction is considered a useful remedy to treat whooping cough and cold.
  • The inhabitants of central Italy, the leaf juice is traditionally used for its depurative, diuretic, and carminative effect, whereas the fruit infusion is used for its stomachic, digestive and carminative properties.
  • In many countries, the fresh leaves of sea fennel are used to prepare soups, sauces, and salads, or they are processed like capers in vinegar; canned sea fennel is registered in the “List of Traditional Agri-Food Product” by the Italian Ministry of Agriculture.
  • The “Rock Samphire Hash” is a traditional dish of the British Isles prepared by using sea fennel leaves mixed with pickled cucumbers and capers.
  • According to Greek legends, the use of sea fennel as food is lost in the mists of time considering that it was served to Theseus by Hekate.

Is there such a thing as 'Plant Retinol'?

Plants do not contain retinol they have provitamin A known as carotenoids. Vitamin A is the name given to a group of fat-soluble retinoids, including retinol, retinal, and retinyl esters. Vitamin A is necessary from human health and is involved in:

  • Immune function,
  • Vision,
  • Reproduction and
  • Cellular communication.

Two forms of vitamin A are available in the human diet:

    1. Preformed vitamin A - Retinol and its esterified form, retinyl ester, preformed vitamin A are found in foods from animal sources, including dairy products, fish, and meat (especially liver).
    2. Provitamin A - Carotenoid is beta-carotene; other provitamins A include: carotenoids are alpha-carotene and beta-cryptoxanthin. The body converts these plant pigments into vitamin A and is by far the most important.

Both provitamin A and preformed vitamin A must be metabolized intracellularly to retinal and retinoic acid, the active forms of vitamin A, to support the vitamin’s important biological functions. Other carotenoids found in food, such as lycopene, lutein, and zeaxanthin, are not converted into vitamin A.

Both retinyl esters and provitamin A carotenoids are converted to retinol, which is oxidized to retinal and then to retinoic acid. Most of the body’s vitamin A is stored in the liver in the form of retinyl esters.


All retinoid forms of vitamin A are used in cosmetic and medical applications applied to the skin. Retinoic acid, known as tretinoin in clinical usage, is used in the treatment of acne and keratosis pilaris. An isomer of tretinoin, isotretinoin is used orally (known as Accutane and Roaccutane) for severe acne.

Cosmetics usually contain retinol esters called retinyl palmitate and tretinoin. Your body converts these into an active form - retinoic acid - that can then be utilized by your skin cells. Animal-derived retinol and Vitamin A derivatives are called retinoids. 

Retinyl palmitate - known as retinol palmitate, is a synthetic form for retinyl acetate that is derived from animal fats, fish oils, and Vitamin A supplements. It is a precursor to retinol. Most retinoic acid is derived from the enzymes in milk or egg, and are generally perceived to be more potent for treating skincare issues. 

Retinoid-like actions Of Crithmum Maritimum

I have created and trialed formulations with both Bakuchiol - the other rather popular plant-based retinol 'alternative' and Crithmum Maritimum, and after extended use of both ingredients, I decided that Crithmum Maritimum offered skin results reflected and supported by the In-vitro and In-vivo tests, which have been undertaken with this ingredient. Another incredibly important reason for choosing to incorporate Crithmum Maritimum into my formulation of Cell Affinity Coactive Serum was sustainability. This plant grows abundantly in the wild, and it is suitable for and is successfully commercially cultivated. 

I have spent hundreds of hours during the research and design process when it comes to selecting ingredients to formulate with, I work with an Earth-First approach if a plant is not sustainable I consider what alternative plants are available. To put it simply I do my due diligence.

Crithmum Maritimum works by stimulating cellular renewal in order to improve the structure of the skin, and in this way contribute to its thickening. It eases the elimination of excess cornified cell masses by reducing their adherence. By helping to thin down this layer, it contributes to the reduction of fine lines and wrinkles harmonizing the complexion. The ability to increase cell renewal along with the synthesis of collagen, proteoglycans, and glycosaminoglycans, it improves the overall quality of the epidermis without causing irritation to the skin.

Backed by science - In vitro and In vivo trials noted Crithmum Maritimum Extract:

  • Softens and brightens the skin,
  • Unclogs pores - preventing microcomendones,
  • Boosts both the quality of collagen and its production,
  • Reduces the appearance of fine lines,
  • Speeds up cell turnover,
  • Evens out skin discoloration and texture,   
  • Reduces skin inflammation,
  • Not contraindicated during pregnancy,
  • Regulates sebum production.


  • Vitamins:  A / E - Rich in Polyphenols & Tocopherols,
  • Antioxidants: Flavonoids / Polyphenols / Caratenoids, 
  • Fatty Acids: Linoleic Acid / Alpha-linolenic Acid / Oleic Acid.

PLANT PART USED: Whole plant
INCI NOMENCLATURE: Crithmum maritimum
Crithmum Maritimum CO2 Extract: This is blended with Caprylic and Capric Triglyceride (non-GMO and not derived from palm oil) This is an emollient that promotes penetration of ingredients into the skin due to being an efficient solvent and therefore, acts as a carrier for fat-soluble vitamins and actives functioning as a component of the delivery system. 


Crithmum Maritimum works synergistically with the other plant sources of Provitamin A I have incorporated into the formulation, namely Carrot Root, Kahai Seed, Rosehip Seed and Fruit, Sea Buckthorn Seed and Fruit, along with Red Raspberry Seed this formulation is incredibly rich in:

  • Provitamin A,
  • Beta-Carotene
  • Carotenoids, 
  • Lutein, 
  • Lycopene.

Together performing as potent antioxidants that assist in the revitalization of dull skin, stimulate cell repair and importantly protect it from further damage from the environment and daily stressors. Supporting the health of your skin.

Cell Affinity Coactive Serum is available Friday 1st November 2019, a limited small batch until stocks last in both 5ml Pipette and 30ml Roller-Ball. If you are a VIP Subscriber you have been emailed a code for complimentary shipping worldwide.

Until next time..

be human | be kind | be you




love letter


Lequeux C, Lhoste A, Rovere MR, et al. Model of in vitro healing to test the influence of dedifferentiated Crithmum maritimum cells on dermal repair and epidermal regeneration.Skin Pharmacol Physiol.2011;24(2):75-80.

Caucanas M, Montastier C, Pierard GE, et al. Dynamics of skin barrier repair following preconditioning by a biotechnology-driven extract from samphire (Crithmum maritimum) stem cells.J Cosmet Dermatol.2011 Dec;10(4):288-93.

Vitamin A. The American Society of Health-System Pharmacists.

Reviewing the Prospects of Sea Fennel (Crithmum maritimum L.) as Emerging Vegetable Crop


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