As the weather gets warmer and clothes become lighter, slimming, and firming products for the body will once again be in the spotlight in shops. These products, which are almost exclusively intended for women, do not aim to make you lose weight (which would be outside the scope of a cosmetic product) but to locally reshape the tissues to tone up and tighten in the lower body (stomach, hips, buttocks, legs) or upper arms, as well as to reduce the appearance of cellulite. Cellulite is particularly visible on the thighs and buttocks, where it gives the skin that characteristic appearance known as “orange peel”. Although cellulite is completely natural, it is often viewed negatively and can affect the body image of those who have it to varying degrees.

Slimming products are no exception to the current trend of “Body-positivity”, which claims that one should take care of one’s own well-being and not feel pressured by the view of society or the gaze of others. The names of these products are now evocative of the benefits they claim to have (e.g., bodyfit, global sculpture, melt with pleasure, second skin effect), the formulas put naturalness in the spotlight with active ingredients that make multiple promises (e.g. ultra-stimulating, energy booster, toning, firming, smoothing, moisturizing, softness) and with fragrances that claim to provide relaxation, soothing or, on the contrary, have an invigorating and energizing effect… The sensoriality of these new products are particularly well documented: it creates surprise with warm (e.g., thermo-active cream) or cold (e.g., shivering gel) effects as well as innovative textures (e.g., crunchy foam, “cocoon” balm) that encourage their use.

If the wording around these products is evolving, their targets often remain the same (e.g., remodeling, surface smoothing, firmness). The techniques for evaluating the effectiveness of these products, which allow the effects to be visualized, are particularly popular. Thus, they can propose:

• The “orange peel” appearance of the skin can be objectively assessed by clinical score on the subjects or on photographs taken under standardized lighting conditions.

A decrease in the number and/or depth of the dimples attests to smoother skin.

Photographs of the appearance of dimples on the back of a thigh before and after 56 days of twice-daily application of a slimming cream.

• In vivo fringe projection allows fine measurements of:
  • the skin surface roughness Sa (µm) in relation to the smoothing of the relief, D0 D56 8
  • the maximum amplitude of the surface St (µm) associated with dimpling,
  • the volume (mm3 ) also reflecting the presence of dimples.

This technique also makes it possible to obtain interesting visuals in 2D/3D imaging of skin relief and dimples.

PRIMOS® fringe projection imaging of the appearance of dimpled skin on a thigh (µm) before and after 56 days of twice-daily application of a slimming cream.

On a larger scale, fringe projection allows volume measurement on areas such as the stomach, buttocks, or thighs, coupled with 2D/3D visuals.

• Low frequency ultrasound (7.5 MHz) allows the thickness of fat tissue to be followed over time, while 20 MHz ultrasound provides information on dermal disinfiltration (related to water retention) and smoothing of the dermalhypodermal junction (related to invagination of fatty tissue in the dermis).

20MHz ultrasound (DermaScan C2D) of the dermalhypodermal junction on a thigh before and after 56 days of twice daily application of a slimming cream

• Cellulite is generally related to alterations in microcirculation leading to a decrease in thermal emissivity. The latter can be visualized with a thermal camera. The application of specific active ingredients coupled with the action of the massage allows a revival of the cutaneous microcirculation associated with an increase in the surface temperature.

Infrared thermal imaging (Ti300) on the back of the thighs and buttocks (°C) before and after 56 days of twice daily application of a slimming cream

In addition to these imaging methods, biometric measurements of skin firmness, hydration, microcirculation as well as quality of life approaches and sensorial analysis complete the assessments.

Do not hesitate to consult them for their future launches.

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Read the entire FOCUS#6 on Slimming here

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