In recent years, there have been many technological advances that have also led to changes in people’s lifestyles and, consequently, in their habits. One of the aspects that have changed is the overexposure of the human eye to artificial light due to the daily use of screens.
In this article, Dr. Juan Sánchez Navés, specialist in Ophthalmology, analyzes the research in which he has participated on the effect of yellow filters and the prevention of eye damage associated with artificial light.
Nowadays, in general, all artificial lighting indoors and on all the screens we use in electronic devices is white LED light. This type of lighting contains a high short wavelength, better known as blue light, which causes eye damage. For elderly people, people at high risk of developing cataracts or patients suffering from diabetes, constant and cumulative aggressions of this white light can lead to premature opacification of the crystalline lens.
The effect of the yellow filter under study
The study in which Dr. Sánchez Naves has participated, called “Modulation of aqueous humor melatonin levels by yellow-filter and its protective effect on lens” has been in charge of analyzing the effects of the yellow filter on eye health. The research, carried out on laboratory animals (rabbits), led to the conclusion that the yellow filter helps to prevent the early formation of cataracts, especially those caused by artificial light.
This novel study concludes that the use of a yellow filter and the concomitant production of intraocular melatonin could be particularly interesting in these cases to prevent early cataract formation.
Melatonin and its antioxidant function
The study also showed how intraocular melatonin production could help prevent premature cataract development. Melatonin has antioxidant properties that are useful in preventing oxidation associated with overexposure to artificial light.
Melatonin is secreted by the pineal gland, although it can also be produced in ocular structures such as the crystalline lens. Even so, what artificial light causes is a reduction in the secretion of this substance. And in this case, what was found is that the yellow filter prevents melatonin from being reduced and thus protects cells from oxidative damage that can eventually lead to cataracts. Therefore, regulating lighting and adding a yellow filter could serve as a therapeutic method to reduce the development of this pathology.
What is the role of the yellow filter?
This research has confirmed that, under laboratory conditions, the yellow filter prevents the reduction of melatonin secretion and thus helps to protect the epithelial cells of the lens from oxidative damage.
This is achieved by two factors:
- The yellow filter blocks the short wavelength of white LED light, which has been associated with oxidative stress damage in ocular cells.
- It was confirmed that the yellow filter increases endogenous melatonin levels, which could contribute to cytoprotection and antioxidant defense.
The study, called “Modulation of aqueous humor melatonin levels by yellow-filter and its protective effect on lens” also found a correlation between melatonin deficiency and diabetic cataract.
Thus, the research concluded that yellow filters modulate the melatonin secretion of the eyes by filtering artificial light and thus maintain the antioxidant properties of the crystalline lens. In this way, the appearance of cataracts can be prevented at an early stage.