This new study reveals a link between gut health and dry eye conditions, indicating that beneficial gut bacteria may have protective effects.
Do you struggle with dry eyes? A new study has found that taking care of your gut health could be the treatment for your eye condition! Confused? Let South First break it down for you.
New research by a team of scientists at Baylor College of Medicine has found a potential breakthrough in the treatment of dry eye disease. The study, presented at ASM Microbe 2023, the annual meeting of the American Society for Microbiology, highlights the effectiveness of a commercially-available probiotic bacterial strain in improving dry eye symptoms in an animal model.
“Although this finding stems from an animal study and further research is needed to bridge the gap between bench and bedside, it presents exciting possibilities for future therapeutic interventions,” says Dr Ravindra Mohan, Honorary Professor of Ophthalmology, Dr MGR Medical University, and Director of Trinethra Eye Care in Chennai.
Speaking to South First, Dr Sanjana Vatsa, Consultant Opthalmologist from Dr Agarwal’s Eye Hospital in Bengaluru, explains that dry eye or keratoconjunctivitis sicca, is a common eye condition characterised by insufficient lubrication and moisture on the surface of the eyes.
“Tears play a crucial role in maintaining the health and comfort of the eyes, as they help to lubricate the cornea, wash away foreign particles, and prevent infections. However, in dry eye disease, the eyes either don’t produce enough tears or the tears evaporate too quickly, leading to dryness, discomfort, and irritation,” Dr Vatsa explains.
Dr Dinesh PN, Ophthalmologist at the Karnataka Institute of Diabetes, says that the causes of dry eye disease can vary, ranging from age-related factors and certain medications to environmental conditions, continuous exposure to gadgets, and underlying health conditions such as Sjögren’s syndrome, lupus, rheumatoid arthritis, diabetes, or thyroid disorders.
Speaking about the study, Dr Ravindra Mohan explains that interestingly, the gut is very far from the eyes and it is difficult to make an association between the two.
“However, it can be noted that emerging research is increasingly establishing a significant link between gut health and a wide range of diseases, revolutionising our understanding of how the microbiome impacts overall health,” he says.
Dr Mohan adds, “From gastrointestinal disorders to neurological conditions, the intricate interplay between gut bacteria and various bodily systems is unveiling new possibilities for therapeutic interventions and paving the way for a holistic approach to healthcare. The same seems to have been applied in this newly-presented study as well.”
Dr Mohan explains that though dry eye disease is a chronic condition that cannot be cured, various treatment options are available to alleviate symptoms and improve eye comfort.
Dry eye also shows that there is some kind of inflammation going on in the body. “As of now, the treatment options include the use of artificial tears or lubricating eye drops, medication to reduce inflammation, lifestyle changes, and, in some cases, surgical intervention,” Dr Mohan adds.
Symptoms of dry eye may include a scratchy or gritty sensation, burning or stinging eyes, redness, sensitivity to light, excessive tearing, blurred vision, and difficulty wearing contact lenses, he says.
The research team’s previous work demonstrated that mice colonised with gut bacteria from individuals with Sjögren syndrome, a condition characterised by severe dry eye, experienced exacerbated eye disease under dry conditions compared to mice colonised with gut bacteria from healthy individuals.
This suggests that gut bacteria from healthy people can protect the eyes in dry conditions. The researchers wanted to see if probiotic bacteria with similar effects could be used as a treatment for dry eye disease.
The team of researchers used a probiotic bacterial strain called Limosilactobacillus reuteri (DSM17938), which had shown protective effects in the gut and immune system. They gave the mice antibiotics to remove some of their beneficial gut bacteria, exposed them to dry conditions, and gave them either the probiotic bacteria or a saline solution. After five days, they examined the mice’s eyes.
The mice treated with the probiotic bacteria had healthier eyes and more cells that produce an important component of tears. These findings suggest that the right probiotic could potentially help treat dry eye symptoms.
Lead author Dr Laura Schaefer from the Baylor College of Medicine, in the study, explains, “The ‘friendly’ bacteria that reside in the human gastrointestinal tract have been associated with overall health and protection against various diseases in different parts of the body, including the gut, brain, and lungs. It is, therefore, not surprising that the gut microbiome could also have an effect on our eyes too.”
The study received support from the National Institutes of Health and the Research to Prevent Blindness Foundation.
Dr Ravindra Mohan explains that five out of 10 patients in a week come to his clinic with complaints of dry eye. This means it is highly prevalent in today’s population.
His first advice is to stop taking antibiotics unnecessarily. Several people self-medicate with antibiotics. This can sterilise the gut completely, the body reacts to it, and several other problems arise from this, he says.
Dr Mohan adds, “While there are a lot of gaps and much needs to be done in this particular research area, we must understand that the Indian diet is anyway rich in probiotics. Curd and buttermilk/lassi are part of our daily food. So, we can definitely encourage people to eat probiotics. Whether this connection between gut health and the eyes is true for humans or not, probiotics have a lot of importance in general keeping of good gut health.“
Dr Mohan says that in earlier times, dry eye was viewed as a disease that would be seen in patients with significant diseases like rheumatoid arthritis, autoimmune disorders, or chemical injury, and mostly in the elderly. But now, with societal changes and exposure to technology, ophthalmologists see dry eyes in people as young as 20 years old.
“On an average, we blink about 10 to 15 times in a minute. So, each time we blink, these tears are re-surfaced and they make sure any bacteria is washed out and act as a protective layer. A huge increase in the use of devices has been one of the primary reasons for the increase in dry eyes,” Dr Mohan explains.
He adds that when we look at a computer screen, laptop or mobile phone, our blink rate automatically reduces. When the blink rate reduces, it’s like keeping water in a plate versus keeping it in a cup. “Evaporative loss is higher when we don’t blink. The other reason is also the fact that most of us are working in AC rooms and we don’t feel the need to drink water. This reduces hydration in the body,” says Dr Mohan.
“Cool, dry wind blowing across our faces, less blinking, less hydration has led to an epidemic of dry eyes. In this context, the study becomes more relevant,” he adds.
His final advice? Blink regularly, stay hydrated, limit screen time, and keep the probiotics going!