"Treating Dry Eye Disease with Diet: Just Add Water?"
Dry eye disease is one of the most common eye disorders,
causing irritation and discomfort, and can decrease functional vision,
and sometimes cause a dramatic deterioration in the quality of life.
About five million American men and women over age 50 suffer
from moderate-to-severe dry eyes, and tens of millions more have mild
or episodic manifestations of the disease at a cost of more than $50 billion.
In terms of treatment there are a bunch of drops and drugs that can help.
We spend hundreds of millions of dollars on things like artificial tears,
but currently there is no therapy available to actually fix the problem.
If drugs don't work, doctors can try plugging up the outflow tear ducts,
but that can cause complications such as plugs migrating
and eroding into the face requiring surgical removal.
Or surgeons can just go and cauterize or stitch up the ducts in the first place.
There's got to be a better way. What about prevention?
Well, dry eyes can be caused by LASIK surgery,
affecting about 20-40% six months after the operation.
With a million LASIK procedures performed annually that's a lot of people,
and sometimes the long-term symptoms can be severe and disabling.
There's a long list of drugs that can do it: antihistamines, decongestants,
nearly all the antidepressants, anticonvulsants, antipsychotics,
anti-Parkinson's drugs, beta-blockers, hormone replacement therapy,
as well as a few herbal preparations.
In the developing world, vitamin A deficiency can start out as dry eyes,
and then progress to become the leading cause of preventable childhood blindness.
Vitamin A deficiency is almost never seen in the developed world
unless you do it intentionally.
There was a report in the '60s of a guy who deliberately ate a vitamin A deficient diet,
living off of bread and lime juice for five years and his eye turned into this.
But better than this poor woman, the member of some cult
that tried to live off of just brown rice and herbal tea,
whose eyes literally melted and collapsed.
There are also a couple case reports of autistic children who refused
to eat anything but French fries, or bacon blueberry muffins and Kool-Aid,
and got vitamin A deficient.
There was a case in the Bronx written up as vegan diet and vitamin A deficiency,
but it wasn't the kid's vegan diet; he refused to eat vegetables,
consuming only potato chips, puffed rice cereal
with non-fortified soymilk, and juice drinks.
His parents lacked the skill in overcoming the child's tendency
to avoid fruits and vegetables.
A plant-based diet may actually be the best thing for patients
with dry eye disease, those who wear contact lenses,
and those who wish to maximize their tear secretions.
People with dry eyes should be advised to lower protein, total fat,
and cholesterol intake, and increase complex carbohydrates,
increase vitamin A content by eating red, orange, yellow, and
dark green leafy vegetables,
increasing zinc and folate by eating whole grains, beans,
and raw vegetables, especially spinach,
ensure sufficient B6 and potassium intake by eating nuts, bananas, and beans,
ensure sufficient vitamin C by eating citrus,
eliminate alcohol and caffeine,
reduce sugar and salt intake,
and increase water consumption to six to eight glasses per day.
Well, we know dehydration can cause a dry mouth.
Might dehydration cause dry eyes?
Seems kind of obvious, but evidently it was never studied, until now.
Is the answer to just drink more water?
Well, we know that those suffering from dry eye are comparatively dehydrated.
They figure that tear secretion decreases with progressive dehydration
just like saliva secretion decreases, giving us a dry mouth.
And indeed, as one gets more and more dehydrated,
the urine concentrates, and so does tear fluid.
But one can reverse that with rehydration, raising the exciting prospect that
improving whole-body hydration by getting people to drink more water
might confer important therapeutic effects for patients with dry eyes.
The researchers recommend eight cups of water a day for women
and ten cups a day for men.