dry eye dx and tx
Alternative Omega-3 Sources
BY WILLIAM TOWNSEND, OD
"Doctor, I just can't swallow these big capsules," my patient remarked when I asked how his meibomian gland therapy was going. It wasn't the first time I'd heard such a comment. In eye care and throughout health care is a growing trend to prescribe omega-3 polyunsaturated fatty acids (PUFA) for a myriad of applications. Omega-3s are essential fatty acids; the body requires them but can't synthesize them. We must consume them in food or as a supplement. Among the many health benefits of PUFAs are reduced blood pressure, improved joint health, reduced triglycerides and lower risk for heart disease and sudden death.
A Need for Omega-3
Unfortunately, the American diet is deficient in omega-3s. Simopoulos (2000) describes a decline in omega-3s over the past 150 years. His study emphasizes the necessity of adequate omega-3 intake for optimal health.
There are three primary omega-3s. Alphalinoleic acid (ALA) is based on a short chain of carbon atoms. The two longer chain omega-3s, eicosapentaenoic acid (EPA) and doscahexanoic acid (DHA), are considered more beneficial. They're found in coldwater, fatty fish such as salmon.
Miljanoviç et al (2005) demonstrated an increased risk for dry eye in women deficient in omega-3s. This study confirms the beneficial effects of long-chain omega-3s.
The brain and retina have high demand for omega-3s. SanGiovanni and Chew (2005) concluded that, "there is consistent evidence to suggest that omega-3s may act in a protective role against ischemia-, light-, oxygen-, inflammatory-, and age-associated pathology of the vascular and neural retina."
Perhaps the most common ocular application is treating meibomian gland dysfunction. Fish consumption could ideally meet omega-3 dietary needs, but unfortunately many individuals won't alter or augment their diet to get the required amount.
In our practice we find that individuals who will eat little or no fish are often amenable to dietary supplementation with omega-3s in the form of fish oil capsules.
A Tough Pill to Swallow
The vast majority of patients seem to have no problem taking 1000mg fish oil capsules, a readily available, inexpensive source of long-chain omega-3s. But some patients don't tolerate the fishy aftertaste; others simply can't swallow the bulky 1000mg capsules, but they still need these nutrients for optimal general and ocular health.
New forms of omega-3s have recently reached the marketplace. For individuals who can't swallow large capsules, Theratears Nutrition (Advanced Vision Research) is a readily available product that incorporates long-chain omega-3s from fish oil and short-chain omega-3s from flax seed oil. The capsules are much smaller and therefore easier to swallow for patients who have difficulty with the 1000mg capsules.
Another recent entry into the small capsule market is krill oil. Krill are shrimp-like crustaceans that live in all the world's oceans. They're very important in the food chain because they feed on phytoplankton and in turn serve as a food source for fish, seals and whales. They're rich in long-chain omega-3s.
Krill oil isn't readily available in many areas, but you can get it through the Internet; we prescribe Neptune Krill Oil (NKO) for our patients and refer them to http://www.doctorstrust.com/ or (800) 240-6046. Other companies also supply krill oil.
For patients who simply can't swallow capsules, consider prescribing Coromega, which incorporates "pharmaceutical grade fish oil into a creamy, delicious pudding-like emulsion." Each packet contains 350mg of EPA and 230mg of DHA. It's available in orange (our favorite), lemon lime and orange chocolate flavors. CLS
For references, please visit www.clspectrum.com/references.asp and click on document #142.
Dr. Townsend practices in Canyon, Texas and is an adjunct faculty member at UHCO. E-mail him at firstname.lastname@example.org.