Safflower Oil: What is its Biochemical Composition?

Safflower oil is an oil extracted from the safflower plant. This plant gets its name from its ancestral use as a dye plant. In the 19th century, it was one of the most widely used plants for dyeing, along with indigo. Beyond its aesthetic properties, the safflower is also cultivated for the precious oil contained in its seeds. The vegetable oil of safflower indeed provides numerous benefits for the skin and is found in various cosmetic products under its INCI name Carthamus Tinctorius Seed Oil. The skin properties of safflower oil come from its active molecules. It is interesting to note that its biochemical composition varies slightly depending on its variety and the geographical area where it is grown.

Safflower oil is rich in linoleic acid.

Safflower vegetable oil contains a high percentage of polyunsaturated fatty acids, specifically linoleic acid. Indeed, 70 to 75% of this omega-6 is found in safflower oil. Linoleic acid is one of the natural ingredients responsible for the nourishing, hydrating, and healing properties of safflower oil. This oil is particularly favored by dry or dehydrated skin and is commonly used to soothe the skin and reduce feelings of tightness.

From a biological perspective, linoleic acid contributes to the formation of the skin barrier by triggering a cascade of biochemical reactions that ultimately lead to the stimulation of cellular renewal. Moreover, this fatty acid is involved in the mechanism of acylceramide synthesis. This is a specific type of ceramide resulting from an amidation reaction between a sphingoid base and linoleic acid. Ceramides are essential molecules for the protection and hydration of the epidermis and ensure good cohesion between cells. Lastly, it's worth noting that linoleic acid is a precursor in the synthesis pathways of several mediators that are highly active in neoangiogenesis and dermal regeneration.

Safflower oil contains oleic acid.

Safflower oil is also rich in oleic acid, a monounsaturated fatty acid. Depending on the plant varieties, it is found between 15 and 20% in vegetable oil. This omega-9 ensures skin hydration and studies have shown that it helps to stimulate sebum production by the sebaceous glands to counteract, among other things, skin dryness. Thus, oleic acid plays a protective role crucial for the skin, aiding it in withstanding external aggressions such as wind, cold, or pollution.

Safflower oil contains saturated fatty acids.

Saturated fatty acids are also found in safflower oil. It is estimated that it contains on average 6 to 8% palmitic acid and 2 to 3% stearic acid. These fatty acids also contribute to the moisturizing effects of safflower oil because they have film-forming properties, meaning they help maintain the hydrolipidic film on the surface of the epidermis. As a reminder, this film, primarily composed of water, sebum, and sweat, forms a protective veil to shield the skin from external aggressions and limit water loss.

Safflower oil contains phytosterols.

Safflower oil also contains plant sterols, known as phytosterols. Notably, these include campesterol, stigmasterol, and β-sitosterol. These lipids have a structure similar to cholesterol and are essential components of plant cell membranes. When applied to the skin, phytosterols have moisturizing, antioxidant, anti-inflammatory, and antibacterial properties.

Phytosterols function primarily by inhibiting the activation of several pro-inflammatory transcription factors, such as NF-κB and Activator Protein 1 (AP-1). They also reduce the activity of collagenase, the enzyme responsible for breaking down the peptide bonds of collagen and its degradation, and have bactericidal and bacteriostatic activity against certain microorganisms like Enterobacter cloacae and Escherichia coli. Lastly, studies have shown that phytosterols possess interesting capabilities of water capture and retention, making them effective humectants.

Several vitamins are present in safflower oil.

Several vitamins are found in safflower oil, with the most abundant being vitamin E and vitamin K. Tocopherols, a class of vitamin E, act primarily as free radical scavengers. The hydroxyl function carried by their aromatic cycle allows them to capture free radicals and stabilize them by providing the missing electron. In addition to protecting the skin and slowing its aging, the antioxidant properties of tocopherols help to preserve the quality of the oil.

When it comes to Vitamin K, this molecule proves to be very useful for accelerating wound healing and reducing skin redness. Indeed, it significantly increases the process of epithelialization, the formation of fibroblasts, collagen fibers, and blood vessels. These various effects were particularly highlighted in a double-blind study conducted with 63 individuals with wounds. For 14 days, some participants applied a "standard" moisturizing cream while others used the same moisturizing cream to which 1% of Vitamin K was added. At the end of the study, scientists observed a better healing in patients who applied the cream with Vitamin K.