Oil or cream: what is the difference in effectiveness?

Oil and cream are often used interchangeably in the bathroom. Yet their cosmetic properties have little in common. More penetrating, richer and more active: oils are precious allies to accompany your slimming ritual and preserve the beauty of your skin.

Oil and cream: a difference in galenics

• An oil is, by definition, a 100% lipid substance. It consists exclusively of fat and contains no water.
• A cream is a homogeneous mixture of fats (especially oils) and a watery phase. This is called an emulsion.

Not all oils are created equal

The oils and fats you find in cosmetics can be of three types:

• mineral: these are substances derived from petrochemicals (liquid paraffin, petroleum jelly).
• Vegetable: composed of triglycerides, they are obtained by pressing seeds or fruits or by extraction using solvents (argan oil, borage oil, etc.).
• animal: they are less and less represented in the cosmetic sphere (mink oil, shark oil).

Mineral oils are the most common in conventional cosmetics. However, their molecules are too large to be absorbed by the skin. They therefore remain on the surface of the skin, where they form an occlusive film. Only vegetable and animal oils can really penetrate the skin, which gives them much more interesting cosmetic properties.

At Lytess, we have chosen vegetable oils for our cosmetotextiles. They are fixed in a microencapsulated form to the fibre of our slimming clothes.

Moisturising creams: lots of water and few active ingredients

Classic moisturizers, such as your night cream or slimming cream, are generally oil-in-water (O/W) emulsions, also known as water-continuous. Remember that they contain a majority proportion of water in which oil droplets are dispersed. If you are curious, you should know that their formulation follows the following pattern:

• water (from 60 to over 80%)
• a complex of fats and lipids (about 20%)
• emulsifiers, to allow the fat and water to mix
• humectants, to attract and retain water (hyaluronic acid, glycerine, etc.)
• active ingredients (only 1 or 2%), which give your cream its properties
• preservatives, which are essential due to the presence of water
• additives (perfume, colouring, viscosity control agent, etc.) which are supposed to improve the sensoriality of the finished product.

Focus on the skin's barrier function

Your skin is covered by a relatively impermeable lipid barrier. This physiological characteristic plays a determining role in the way it interacts with an oil or cream.

We tend to forget it, but the skin is above all a protective shield. It regulates exchanges between your body and the outside world, in both directions. To do this, the skin's surface is equipped with a waterproof coating that protects you from physical, biological and chemical aggressions. This barrier function is mainly provided by two elements:  

• the hydrolipidic film: a mixture of a lipidic fraction (sebum) and an aqueous phase (sweat). It covers the surface of the skin and gives it its acid pH. It also plays an occlusive role: it slows down the evaporation of water rising by diffusion from the deep layers (the dermis) to the upper layers of the skin.

• the stratum corneum: this is the most superficial layer of your skin. It is made up of a "wall" of dead cells spread over several strata and made up of keratin, a hydrophobic protein (which cannot interact with water). This impermeability is reinforced by the liquid in which these cells are bathed: the intercellular cement, composed of lipids (ceramides, fatty acids, cholesterol).  

How a cream works: surface moistening

What happens when you apply a cream to your skin? As it is mainly composed of water, part of its progress is blocked by the lipidic nature of the skin barrier. It is therefore bound to gradually evaporate. This phenomenon is slowed down by the combined action of humectants and oils, which temporarily trap a small portion of water in the horny layer and give the skin a plumped-up appearance. At the end of the day, only a very light protective film usually remains.

What about the active ingredients? They are carried along by the continuous phase of the emulsion (water, in the case of a classic cream) and remain, with it, in contact with the corneal layer. Their concentration evolves as the water evaporates: their absorption is at its maximum when they reach saturation in the water. Only then will they be able to break free from their vehicle and penetrate the skin.  

Oil: optimal bioaffinity with the skin tissue

Some vegetable oils have the particularity of being composed offatty acids that are very close to the lipids that make up the skin's surface. Unlike water, they are therefore able to penetrate more deeply into the different layers of the epidermis.

By infiltrating these layers, the fatty acids in vegetable oils reinforce the skin's anti-dehydration barrier: they reconstitute the fatty phase of the hydrolipidic film and make up for any lipid deficiencies in the intercellular cement. In short, vegetable oils are indirectly hydrating, since they regulate water loss by evaporation. They are excellent emollients, leaving the skin soft and supple.

This affinity of oils with skin lipids facilitates the transit of the active ingredients they carry with them. Their chemical structure is therefore particularly interesting in the formulation of slimming cosmetics, which must reach deep layers to be truly effective. Are you beginning to understand why we prefer oils?

Vegetable oils: active substances in their own right

Vegetable oils have another advantage: they are active ingredients in their own right. They do not just carry the main active ingredients of the cosmetic treatment into the skin. They also provide others that they naturally contain and that give them specific properties.

These active substances are contained in the unsaponifiable fraction of vegetable oils. They are mainly :

• carotenoids, precursors of vitamin A
• tocopherols, including vitamin E
• phytosterols, the equivalent of plant cholesterol.

A vegetable oil contains up to 3% of unsaponifiable matter. This rate rises to 15% for shea butter! Apart from its consistency, it has the same properties as vegetable oils. You will find it in several of our slimming undergarments, such as the Shorts comfort slimming or the lace shorty slimming flat stomach.

Lytess: oils for your figure

Vegetable oils are the basis of our slimming solutions. They are combined with anti-cellulite, draining or toning active ingredients, then encapsulated in polymer envelopes that preserve their nutritional qualities for a long time. Combined with our technical textiles, they act on the areas that are bothering you to detoxify, smooth or firm your skin. In all simplicity!

Explore our styles of slimming clothing and underwear and treat yourself to the benefits of a careful selection of plant oils and butters. All are known for their high nutrient content and excellent affinity with the skin. Among our favourites:

• Sweet almond oil: very emollient, it is at the heart of the moisturising action of most of our products.
• apricot kernel oil: rich in omega-6, it is known for its great penetration capacity.
• Mango butter: a reserve of essential fatty acids and antioxidants, it has lipid-replenishing properties that are highly appreciated in the care of dry skin.