Frequently Asked Questions

The first effects—stronger hair and less shedding when washing—are generally felt within the first 4 to 6 weeks.

Visible growth requires a full 90-day routine. Hair grows an average of one centimeter per month: patience is part of the protocol.

Yes. Our routine is compatible with straightening treatments and hair coloring. However, since the shampoo contains a mild sulfate (SLES), it may slightly reduce the lifespan of certain treatments, especially if used frequently.

If you wish to preserve your straightening or coloring as much as possible, we offer a shampoo-free routine (serum, mask, and gummies) that can be complemented with a sulfate-free shampoo of your choice.

Yes. The kit was designed for all hair types, including fine and thinning hair. Our active ingredients work directly on the scalp to stimulate follicle activity and promote growth and volume.

Our kit effectively combats hair loss linked to stress, deficiencies, hormonal changes, or an unsuitable routine. In cases of diagnosed alopecia, we recommend consulting a dermatologist before starting the routine.

Yes, each product is formulated to act independently. However, for a complete hair transformation and visible results in 90 days, our Growth Kit offers optimal scientific synergy between its components.

No. Our gummies are formulated with vitamins, minerals, and active ingredients targeted for hair health, with no hormones and no excess added sugars.

No, the unusual changes in hair fiber are primarily the result of hormonal imbalances. Our formulas do not contain any hormones. As for biotin, it is precisely dosed to ensure a targeted action without affecting body hair growth.

How do I use the Hair Growth Kit routine?

You can find the complete user guide at the following link:

Shampoo — 2 to 3 times a week. Lather in your hands, then massage into your scalp with your fingertips for 1 to 2 minutes. Leave on for 1 to 2 minutes before rinsing.

Mask — Apply before or after your shower, to towel-dried (never soaking wet) hair, only on the lengths. Minimum processing time: 15 minutes.

Gummies & Keratin — One dose per day, at a time of your choice.

Serum — A few drops on the part, temples, and top of the head. Massage the scalp with your fingertips, using a pressing motion rather than rubbing, to help with absorption.

The mask is applied to wet hair, before or after shampooing depending on your preference. Leave on for 5 to 10 minutes, then rinse thoroughly.

2 to 3 times a week is the ideal frequency for most hair types.

Yuka does not take dosage into account. The active ingredients that lower the rating are precisely those that ensure the product's effectiveness, and which are intentionally dosed.

We have chosen to keep a modern sulfate (SLES) because it provides effective scalp cleansing, which is essential for removing sebum and residue so that the active ingredients can work under optimal conditions. Contrary to popular belief, it is not the presence of a sulfate that determines the quality of a formula, but its type, concentration, and the overall balance of the formulation. Rather than following a marketing trend, we have prioritized a high-performance formula, developed with a specialized French laboratory, while always keeping efficacy and transparency at the forefront.

Your order will be dispatched from our warehouse within 24 business hours. Delivery then takes 1 to 2 business days within Metropolitan France.

A tracking link will be sent to you by email as soon as your order has been shipped. You can track each stage of the delivery in real time.

You can also track your package at the following link: HERE

Yes, we ship to Europe and the United States. Delivery times and shipping costs are specified at checkout.

If your order has not yet been shipped, please contact us as soon as possible and we will take the necessary steps. Once shipped, the order can no longer be modified.

If you follow the routine for 90 days and do not see results, you will receive a full refund.

This guarantee is based on the confidence we have in our products and the results of the routine.

To take advantage of it, contact us at support@laboratoiresvinci.fr or via our contact page.

You have 14 days after receipt to return unopened products in their original packaging. Contact our team to initiate the return.

Contact us at support@laboratoiresvinci.fr or via our contact page, with a photo of the package and the products concerned. We will process your request as a priority and find an appropriate solution.

Our team will respond to you by email (support@laboratoiresvinci.fr), from Monday to Friday. We will assist you as soon as possible.