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Here's How Revolting Your Contact Lenses Are

June 17, 2015

Story at-a-glance

  • The microflora of the eye differs in people who wear contact lenses and those who do not
  • Contact wearers’ eye microbiome resembled more closely the microbiome of the skin than that of the eye, with three times more of certain types of microbes
  • Some of the increased microbes are linked to inflammatory eye conditions, such as conjunctivitis, keratitis (corneal infection), and endophthalmitis

By Dr. Mercola

You are not only a human being… you're a microbial being that provides a home to nearly 100 trillion bacteria, fungi, viruses, and other microorganisms that compose your body's microflora. Advancing science has made it quite clear that these organisms play a major role in your health, both mental and physical.

Much of the research to date has focused on the role of microbes in your gut and skin health, but this is only the beginning. Your eyes have a microbiome, too, one that has been largely neglected by researchers to the extent that its functions remain unknown.1

A new study presented at the annual meeting of the American Society for Microbiology has begun to piece together the puzzle, however, by examining the colonies of bacteria living on the eyes of people who wear contact lenses and those who do not. Their findings add to the growing knowledge that modern lifestyles are tinkering with our microbiomes… with potentially dangerous effects.

Wearing Contact Lenses Alters Your Eyes' Microbiome

After comparing the quantity and types of bacteria on the surface of the eyes in contact-lens wearers and non-wearers, those wearing contacts had higher microbial diversity. The contact wearers' eye microbiome resembled more closely the microbiome of the skin than that of the eye, with three times more of the following:2

This is an important news for the 71 million contact lens wearers worldwide,3 as some of the increased microbes are linked to inflammatory eye conditions, such as conjunctivitis, keratitis (corneal infection), and endophthalmitis. This may be one mechanism by which using contact lenses increases the risk of eye diseases and infections.

The altered microbiome is thought to be the result of fingers habitually touching the eye, transferring in microbes that wouldn't ordinarily exist in such high numbers. It could also be due to alterations to the eyes' immune system due to the lens' direct pressure on the eye.4 Another alternative is the contact lenses may favor skin-like bacteria in the eye.

Senior study investigator Maria Gloria Dominguez-Bello, a microbiologist at NYU Langone Medical Center, stated:5


Is Your Eye Microbiome Linked to Dry Eye?

Although the eyes' microbiome is only beginning to be understood, there's reason to believe it may play a significant role in eye health. According to a proposed study being sponsored by the Singapore National Eye Center:6

"Over the course of evolution, various microbes, especially bacteriae, have come to colonize the ocular [eye] surface as commensals. The commensals have a role to maintain the homeostasis of the ocular surface.

The innate immunity of the ocular surface is very active, and consists of active mechanisms to suppress inflammation. For example, there exist macrophages, dendritic cells, suppressor cells, regulatory cells, B cells, IgA, lysozyme, anti-microbial peptides and barriers against external agents.

The normal commensals of the ocular surface maintain a basal level of activation of innate defense by stimulating the pattern recognition receptors on ocular surface epithelial cells.

This normal composition of microbes is important since inflammation and infection will result if there is introduction of a pathogenic strain that overcomes the flora, or if a dominant strain secretes excessively immunogenic products."

The proposed study wants to determine if dry eye may, in fact, be microbial in origin. "Since dry eye is a known inflammatory disease of the ocular surface, this is one way that microbes can contribute to the pathology," they note.

The Ocular Microbiome Project

The Human Microbiome Project, which was initiated in 2008 and funded by the National Institutes of Health (NIH), aimed to "characterize microbial communities found at multiple human body sites and to look for correlations between changes in the microbiome and human health."

Unfortunately, this multimillion-dollar effort did not include the surface of the eye. So, in 2009 researchers at Bascom Palmer Eye Institute in the US initiated the Ocular Microbiome Project.

While it was once believed the surface of the eye was relatively devoid of microbial life, due to tears and blinking "washing" it away, research from the Bascom Palmer Eye Institute found the opposite, that the surface is "populated densely" not only with bacteria (about a dozen different types were dominant) but also viruses.

"People can have a huge variation in microflora and still have healthy eyes, making our job difficult, but really amazing," researcher Valery Shestopalov told The Scientist.7

Also interesting, the researchers found that only about half as many bacterial varieties were presented during keratitis infections, which are serious infections of the cornea.

The most prominent strains were Pseudomonas, and the changes to the microbiome occurred long before the eye infections were diagnosed, which suggests such changes could be used to diagnose the infection earlier, or perhaps could one day be changed to prevent the infection entirely.8

In this case, the researchers believe contact lens wearers may be more prone to infections, because the lenses provide a surface upon which pathogens can colonize. Separate researchers have developed an antimicrobial contact lens they believe will counteract the problem, without altering the normal, commensal bacteria of the eye.9

Many Health Problems Can Arise From an Imbalanced Microbial Community

It's not only your eyes that may suffer from a disrupted microbiome. Researchers have discovered that microbes of all kinds play instrumental roles in the functioning of your body. For example, beneficial bacteria, also known as probiotics, have been shown to:


Researchers are actually starting to recognize gut microbiota as one of your unappreciated "organs."10 It's even been suggested that it would be more apt to view your body as a "super organism" composed of symbiotic microorganisms.

The beneficial nature of this symbiotic relationship extends beyond the so-called "friendly" bacteria. Even microorganisms you'd typically consider "bad" or pathogenic can play an integral role in the maintenance of health and disease prevention. In addition:

When you eat too many grains, sugars, and processed foods, these foods serve as "fertilizer" for pathogenic microorganisms and yeast, causing them to rapidly multiply. The best way to support microbial diversity is to instead eat a varied diet, including plenty of fiber-rich vegetables and fermented foods while avoiding antibiotics. Dietary changes are known to impact your microbial diversity drastically in as little as two weeks, but it's unknown whether this has any effect on the microbiome of the eyes.

Are There Other Health Risks of Wearing Contact Lenses?

An increased rate of infection is the most well-known risk of wearing contact lenses. Each year, contact-lens wearers visit doctor's offices and emergency rooms close to 1 million times due to eye infections, often caused by improper use of contact lenses (such as leaving them in overnight or not cleaning them properly).11 Corneal abrasions, corneal ulcers, and even infections severe enough to cause blindness can occur.

It's recommended that you cleanse and disinfect your lenses properly and use fresh lens solution each time. Don't "top off" or reuse lens solution. Exposing the lenses to any type of non-sterile water can also be problematic, and it's also recommended that you remove contact lenses prior to swimming and sleeping for the night. Your contact lens storage case should be replaced every three months.12

Contacts, and glasses, also serve as a filter and do not allow all 1,500 wavelengths of sunlight to pass through to your retina where they are absorbed into your brain. Wearing glasses or contacts continuously may potentially increase your risk of depression, as your brain will be deprived of many of the valuable frequencies that are in sunlight.

Improve Your Vision with Relaxation

If you're trying to decide between contacts or glasses, the latter will be far less disruptive to your eye health, particularly where your microbiome is concerned. However, even then by wearing glasses, you're essentially retraining your eyes to strain in order to see all day long, which is the opposite of what promotes a healthy vision. Your vision is not compromised because of weak eye muscles. They're strong enough. They're just too tensed to work properly, so you have to relax them. The Bates Method is a mental approach that can help.

The problem is that once you start wearing corrective lenses, you're actually worsening your vision. This progressive worsening of your vision can lead to a defeatist mentality if you don't realize that what you're doing is creating the problem. Greg Marsh, a certified natural vision coach, explains:

"Dr. Bates' keyword is 'strain.' If you strain your eyes, strain your thoughts, and strain your vision, these muscles are going to start getting tight. The strain is the essence of everything. Imagine you're on a tightrope, you're walking, and you're feeling your way forward. That's how the eyes want to work. If you get tense on a tightrope, you're dead, right? Instead of thinking of it as exercises, you have to go into it in a really subtle way; it's more like a meditation."

Be certain that you try the experiment Greg discusses in the video above by creating a pinhole with your hand and surprising yourself with how clear your vision becomes without any corrective lenses. Just bend your finger to create a small pinhole between the skin folds. Now hold the pinhole in front of your eye and notice how much more in focus everything is that you're looking at. As they say, seeing is believing, and this will go a long way to convince you that you can actually see well without corrective lenses.

Going Without Glasses Might Help Improve Your Vision

Ideally, you'll want to remove your glasses (or contacts) whenever you can safely do so. Also make sure you have appropriate lighting, especially when reading.

"The amount of light is huge," Greg notes. "While somebody is making the transition from needing glasses to not needing glasses, things like using more light really help, like if you're reading a book."

The two most common eyesight conditions requiring glasses are myopia (nearsightedness, which usually appears in childhood or during teenage years) and presbyopia (a type of farsightedness that leads to reading glasses at middle age). They both are very responsive to the Bates Method, and in fact, the approach is nearly identical. If you have a mild prescription, you can simply go more and more frequently without glasses as you improve your eyesight. Of course, you should always wear glasses if they are required for driving, until you pass your vision test without them.


Relax like this for at least two minutes. Then remove your hands, open your eyes, and notice whether anything looks clearer. Usually, it will. Also remember that your mindset is important. With faith in yourself and your body's self-regenerative ability, the toughest hurdle is learning to relax, so your eyes can function in accord with their natural design.

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Sources and References

  • 1 TIME June 1, 2015
  • 2, 3 Washington Post June 1, 2015
  • 4, 5 WebMD May 31, 2015
  • 6 ClinicalTrials.gov Ocular Surface Microbiome in Dry Eye Patients
  • 7, 8 The Scientist October 1, 2014
  • 9 Optometry & Vision Science: May 2014 - Volume 91 - Issue 5 - p 570–581
  • 10 Scientific American November 25, 2013
  • 11 Washington Post November 13, 2014
  • 12 US FDA, Contact Lens Risks
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