THE LIFESAVING POWER OF TEARS
Health
What are tears? You might just think of them as salty water, but in reality they are a lot more than that. Following the recent discoveries in the field of biology, it has emerged that it is more accurate to define them as filtered blood: they transport nutrients and oxygen to our eyes while simultaneously removing waste from them. Besides, they serve at the forefront in combat against pathogens and also aid in healing injuries.
Currently, blood tests dominate different markers of illness, such as checking the body temperature, sense of smell, etc. This is because our blood contains a number of chemicals, each of them associated with the detection of a particular disease or illness — for instance, glucose signals diabetes mellitus, while certain enzymes point towards possible liver disease. After acquiring a blood sample of a subject who is suspected to have fallen victim to a specific disease, the blood test simply confirms the absence/presence of the chemical(s) affiliated with that disease in the blood. This illuminates whether the subject has really contracted that disease or not, and subsequently, the doctors are enabled to take a suitable action.
However, a research has come to light recently, claiming obliquely that this faculty is not exclusively possessed by the blood. Tears share it too! The research has manifested that numerous chemicals that act as signatures of many of the most prevalent and detrimental diseases, including cancer, multiple sclerosis, diabetes mellitus, cystic fibrosis and Parkinson’s disease, exist in tears. Furthermore, work is already underway to endorse the use of such chemicals to diagnose Alzheimer’s disease, and a technology, called TearExo, has been developed to screen for breast cancer by utilizing the tears collected by the patients themselves.
Quite evidently, using tears to detect diseases will certainly bring several advantages. First and foremost, the cost of testing can greatly be reduced. Tear testing will provide a cheaper alternative route to testing and in this way help us to avoid blood tests, which are expensive and put a strain on one’s pocket. In addition, tear testing will be considerably convenient. With the assistance of technology, devices can be manufactured that will allow us to self-administer a tear test, without having to deprive ourselves of the comfort of our homes. Moreover, tear testing will be rapid. Since it can be self-administered by ourselves as stated earlier, there will be no need to spend any time visiting a laboratory in order to take a blood test and, hence, shortening the overall process.
But the potential of tears as indicators of health goes well beyond the narrow scope of occasional testing. Smart contact lens is a propitious tear-based technology that continuously keeps track of a patient’s biomarkers, thus significantly improving disease prevention and early detection. This technology has drawn the attention of major companies, like Google, Novartis, etc., and is currently under development in research laboratories around the globe. One big step in its development came in 2019 with the creation of the first stand-alone contact lens merged with a battery. Lately, a smart contact lens has also been fabricated to constantly monitor glucose presence and treat diabetic retinopathy. Although the fact that a smart contact lens will not be available for commercial use for a few more years ensuing its production seems plausible, it will be a huge success once it rolls out. This is primarily owing to the fact that a massive amount of people already wear ordinary contact lenses, and switching to a smart version will be pretty simple for them.
Apart from smart contact lenses, tears can also be used to keep a check on health in unusual circumstances. In 2018, for the purpose of monitoring astronauts’ health in space, NASA proposed to use tear makers. Tear markers from veteran astronauts with space exposure and new astronauts without space exposure would be used to set up a health database, allowing us to better comprehend the effects of long-term exposure to space environmental factors, such as radiation, weightlessness, etc., on human health. As a consequence, this might even serve as one of the first stepping-stones toward making space colonization a living reality!
When it comes to tears, something considered to be so trivial, you may already be surprised to learn all the aforementioned information about it. However, if you do not find it astounding enough, let me mention that that is just the tip of the iceberg. We are yet to discover its full potential, and that time may not arrive before several years. Nonetheless, one thing is clear: the lifesaving power of tears is undeniable.
