Today, there are numerous ingredients used for hair growth or strengthening on the market, and you have probably often come across advertisements claiming to "prevent hair loss in just so much time." However, to truly say that some ingredients have the potential to achieve the desired effect, it is necessary to review the available scientific literature.

It should be noted immediately that hair loss is not an area where significant resources are invested in research, compared to numerous chronic diseases that affect global health. However, hair loss can cause psychological stress and reduce an individual's quality of life. At this moment, due to funding priorities, hair loss is still not high on the list, so it is not to be expected that the scientific literature on this topic will be extensive. Nevertheless, certain ingredients have stood out for their positive effects, and in relatively recent research.

Placental proteins and plant-based ingredients

In a review article published in November 2025, it is emphasized that the independent effect of placental proteins was investigated in two clinical studies, and based on current knowledge, it can be concluded that they are effective in reducing hair loss and stimulating hair growth, although, as always, additional research is needed.

The first study included 74 subjects and showed a superior effect of these proteins compared to 2% minoxidil, while the second showed that the use of these proteins accelerated the growth of completely shaved hair by 23.6% after 2 weeks and 55.7% after one month.

It is interesting that the same review article also mentions hydrolyzed soy proteins, but they have never been studied as a standalone ingredient in a hair growth product, only in combination with other active ingredients. You can find both ingredients in Hair Regenerator Serum Forte. The same serum also contains an extract of the plant Lepidium meyenii (maca), a plant that grows high in the Peruvian Andes. The extract of this plant is rich in beneficial substances (carbohydrates and proteins) which have shown in research a protective effect on the hair follicle, reduction of inflammation at the hair root, stimulation of factors affecting hair growth, and delay of the hair shedding phase.

Peptides and Capixyl™ complex

Another Nuggela & Sulé product, Anti-Hair Loss Serum Forte, contains patent Capixyl™, a complex of acetyl tetrapeptide-3 and red clover extract (rich in biochanin A). This combination was investigated in a clinical study in people with hair loss that lasted 24 weeks, and the results showed efficacy equal to synthetic minoxidil at a concentration of 3%.

Red onion in hair cosmetics

While the ingredients listed above are relatively new, both in research and in hair growth products, research on the topically applied effect of red onion (the one we eat) has existed for more than 20 years. One of the first studies used squeezed red onion juice. Today, thanks to advances in pharmaceutical technology, active components are available in formulated products such as Nº1 shampoo and conditioner (root application).

According to recent findings, the effect of red onion juice is linked to its composition: zinc content helps in the production of essential oils for the scalp and prevents dandruff-related hair loss, while sulfur contributes to strengthening and thickening the hair. Review papers state that onion prevents hair loss, promotes hair growth, strengthens and thickens hair, and participates in the creation of healthy skin and hair cells. It has proven particularly effective in alopecia areata, with high success rates recorded in clinical trials.

Important note

Before choosing hair growth and strengthening products, it is recommended to consult a doctor or pharmacist to rule out other conditions that may affect hair. Hair growth and strengthening products are used as additional therapy for hair recovery, as well as for quality of life.

Assist. Prof. Dr. Sc. Josipa Bukić, Univ. Spec. Pharm.

article author

References

1. Spiewak R, Szendzielorz E. Ingredients of Trichological Shampoos with Alleged Beneficial Effects on Hair - What Is Really Known About Their Efficacy? Cosmetics. 2025;12:262.
2. Szendzielorz E, Spiewak R. Placental Extracts, Proteins, and Hydrolyzed Proteins as Active Ingredients in Cosmetic Preparations for Hair Loss. Appl Sci. 2024;14:10301.
3. Le Roux M et al. Hair growth and protection properties of Maca root extract. J Drugs Dermatol. 2019.
4. Lueangarun S, Panchaprateep R. Capixyl™ vs 3% Minoxidil. J Clin Aesthet Dermatol. 2020.
5. Sharquie KE, Al-Obaidi HK. Onion juice for alopecia areata. J Dermatol. 2002.
6. Elnady RE et al. Future of Alopecia Treatment. Pharmaceutics. 2025.