Detecting Cancer, Diabetes, Alzheimer's, and Other Health Issues Through Your Eyes
Written by Susan Parker | Updated on June 22, 2025
Reviewed by Susan Parker
11 sources cited
Overview
Whether triggered by sadness or joy, tears of emotion provide valuable insights into your overall well-being. Tears have emerged as a promising indicator of an individual's health status, with NASA even considering their use for monitoring astronauts' health during space missions.
Scientists are currently investigating the potential of tears as a low-cost, non-invasive, and easy-to-collect medium for medical examinations.
Besides their role in lubricating and safeguarding the eyes, tears serve essential functions such as delivering oxygen and nutrients to eye tissues, removing waste, protecting against pathogens, dust, and debris, and aiding in the healing of injuries.
Furthermore, tears contain components present in the blood, making them potential biomarkers for various diseases, including cancer.
Insightful Testing Approach
In Japan, Professor Toshifumi Takeuchi from Kobe University has been working on a test utilizing advanced computer chip technology for the early detection of breast cancer. His research centers on exosomes, which are cell-secreted components carrying fats, proteins, and genetic material. Exosomes can be detected in bodily fluids like tears and may transport mutated genes and abnormal proteins in the initial stages of breast cancer in women.
Professor Takeuchi and his team successfully utilized tear samples for the first time to identify cancer-related intact exosomes, effectively distinguishing between healthy individuals and breast cancer patients. They suggested that this method could be adapted for detecting other forms of cancer.
Professor Takeuchi highlighted the simplicity of self-collecting tear samples using filter paper, emphasizing the potential cost savings and quicker cancer detection compared to mammograms.
Meanwhile, researchers at the University of Debrecen in Hungary are working on a tear-based test for diagnosing Alzheimer's disease, showing promising early outcomes.
Accurate Alzheimer's Detection
Tears contain numerous proteins involved in immune and inflammatory processes. A study aimed to assess these proteins and their correlation with Alzheimer's disease. The study included patients with Alzheimer's disease and healthy subjects, with a combination of four proteins demonstrating high sensitivity and specificity in detecting Alzheimer's disease.
At Maastricht University in The Netherlands, a preliminary study focusing on amyloid beta-42 and tau proteins in tears of Alzheimer's patients is slated for expansion to include 306 patients.
In Japan, Dr. Masakazu Aihara from the University of Tokyo is researching a non-invasive method for measuring blood sugar levels in individuals with diabetes without invasive procedures.
Straightforward Diabetes Assessment
While various non-invasive tests for measuring blood sugar levels have been developed, the monitoring of glucose levels from tears was first explored in 1937. Dr. Aihara's research on measuring glycoalbumin (GA) levels in tears revealed a strong association with blood glucose levels over the preceding two weeks among diabetic patients.
The potential of tear testing goes beyond cancer, Alzheimer's disease, and diabetes, as markers for numerous other conditions such as multiple sclerosis, cystic fibrosis, Parkinson's, and even coronavirus have been identified in tears. This hints at the potential for a rapid, cost-effective, and potentially self-administered diagnostic tool in the future.
