BIOSCOPE

Bioengineers Current Journal and Paper in Review

Vol. 10

Herbal Skincare: Exploring the Potential of Herbs to Fight against UV Radiation

A Review by the Journalism Division of SBE UISC 2022

Based on the article Herbal Products as Skincare Therapeutic Agents Against Ultraviolet Radiation-Induced Skin Disorders by Sharma, R.,Deep, A., and Abdullah, S. from the Institute of Transdisciplinary Health Sciences and Technology and World Ayurveda Foundation

Published in Journal of Ayurveda and Integrative Medicine on 29th of December 2021

(https://doi.org/10.1016/j.jaim.2021.07.016)

Ultraviolet Radiation: What Makes Them Dangerous?

Ultraviolet radiation (UVR) has increasingly been proclaimed as a health hazard, particularly to our skin and eyes. While UVR provides useful effects like stimulating vitamin D synthesis and destroying pathogens, overexposure leads to damaging effects, including degradation of extracellular matrix, sunburn, tanning, photoaging, genetic mutation, immune suppression, epidermal hyperplasia and skin cancer development. This has raised awareness of the danger and changed people’s lifestyle to avoid sunlight.

Subtypes of UVR

There are three subtypes of radiation from UVR based on their wavelengths and biological effects:

 

  • UVA is termed as long-wave radiation with wavelength between 320 and 400 nm, which enables it to be absorbed into the deep dermis. 

  • UVB is known as mid-UV with wavelengths ranging from 290 to 320 nm and is mostly consumed or dissipated within the epidermis. UVB is a complete mutagen that causes the most photodamage to the skin, which makes it declared to be more hazardous than the UVA. There is a large variability in UVB radiation due to factors such as latitude, altitude, seasons, clouds, aerosol, daytime, and ozone layers.  

  • UVC has the shortest wavelength around 200 and 290 nm and is also absorbed into the epidermis and has germicidal properties, hence commonly referred as UV Germicidal Irradiation based on its usage to kill viruses and microorganisms

The intensity of UVR is conditional, so it is highly advised to prepare protection against overexposure of UVR in anticipation of the said factors.

Hidden Risks of Commercially Available Sunscreens

The current cosmetics are made with synthetic chemical substances that may lead to dermal toxicity in the long run. Specifically for sunscreen products, the inorganic UV filters employed for solar protection are suggested to be the most frequent cause of dermal toxicity.

  • Commonly used chemicals like titanium dioxide (TiO2) and zinc oxide (ZnO) provide protection by scattering and reflection of UVR. However, both run into the risk of phototoxicity, a light-requiring chemical-induced skin irritation without involvement of the immune system. 

  • A UV absorbing chemical called benzophenone-3 (BP-3) has been found to be a major cause of allergic reactions, termed as contact dermatitis.

  • Due to their reflective capability, titanium dioxide and zinc oxide tends to produce an opaque and white tone on the skin, resulting in a pale appearance which is not suitable for cosmetic use.

  • Other oxides such as alumina, ceria, and zirconia are formulated as nanoparticles to decrease the reflection of visible light, thereby producing less white coloration when applied to the skin. Nevertheless, these oxides have high photocatalytic activity that facilitates the generation of reactive oxygen species. In the presence of light, they can oxidize and degrade other ingredients in the formulation, raising safety concerns.

Although sunscreens offer benefits, there are numerous safety challenges that need to be overcome.

Herbal Plants and Their Medicinal Ability for the Skin

Medicine derived from plants has been produced since ancient times around 2900-2600 BC, with approximately 1000 plants documented. Modern studies have also proven the therapeutics effects to the skin from some plants, like aloe vera, neem, papaya, turmeric, amla, gingko, liquorice, tulsi, grapevine, tea tree, babchi, sandalwood, lemon, soybean, papaya, garlic, olive oil, and ocimum.

  • Most herbal ingredients possess high contents of polyphenols and flavonoids, exhibit protection from detrimental effects of UVR, and promote the treatment of UVR-induced diseases

  • Aloe vera is therapeutically used for treating cuts, burns, and eczema

  • Neem, liquorice, and tulsi have been found to possess beneficial properties like immuno-modulator, anti-inflammatory, anti-oxidant, anti-microbial, and anti-carcinogenic

  • Papaya can be used to cure eczema, dermatitis, and psoriasis

  • Babchi can be used for psoriasis, leukoderma and vitiligo (loss of skin color due to dying pigment-producing cells), and leprosy

  • Amla has anti-aging property.

  • Sandalwood is good for acne, eczema, atopic dermatitis, psoriasis, and has anti-inflammatory as well as anti-proliferative properties

  • Turmeric is used for treating scleroderma and inflammation

  • Gingko is great for healing skin wounds

  • Herbal ingredients have been widely used to formulate products for cosmetic or for skin pathological states because they have fewer side-effects, better patient tolerance, cheaper cost, and generally acceptable by people.

  • Herbal products for the skin are traditionally formulated into creams, gels, ointments, lotions, and foams for topical application 

There are over a hundred of scientifically validated herbal products related to medication for skin disorders caused by UV radiation. Identification of the agents carrying the therapeutic properties and the study on synergistics effects from the combination of different herbal sources have opened up the therapeutic potential of herbal material against UV irradiation. The findings have shown us the tremendous need to study various herbs and develop herbal formulations based on scientifically validated procedures for therapeutic as well as beautification purposes.

Additional readings:

Explore these articles to find out more about sun protection factor in herbal substances and an in-depth review of spruce bark as a potential herbal sunscreen!