Food contains two types of fatty acids known as Omega-3 and Omega-6. They are essential for our health and as our body cannot manufacture them, must be in our diet.
The good and the bad
Omega-3 is a ‘good fat’ which is used by the body to both produce anti-inflammatory compounds and block the activity of inflammatory mediators. Omega-6 is a ‘bad fat’ that promotes inflammation. It is not always possible to decrease dietary Omega-6 intake, but adding Omega-3 to your diet is a very effective way to reduce inflammation.
In the eye Omega-3 supplementation reduces the risk of macular degeneration and is used in the treatment of posterior blepharitis and dry eye. Omega-3 reduces inflammation in the eyelid margin and provides the meibomian glands with essential fatty acids with which to synthesise their oily secretions. Patients with a higher dietary Omega-3 intake are less likely to have dry eye symptoms.
Beef, dairy products and the vegetable oils found in biscuits and snack foods are high in Omega-6. Western diets are rich in animal and vegetable fats and many New Zealanders suffer from Omega-3 deficiency.
Omega-3 rich food
The best sources of Omega-3 are:
- Dark, oily, coldwater fish such as salmon and tuna
- Flaxseed oil and walnuts
- Capsules of fish and flaxseed oils, available from pharmacies and health food stores
The Omega-3 fatty acids in fish oil and flax seed oil are different. Fish oil is rich in long chain Omega-3 which suppresses inflammation. Flax seed oil contains higher levels of short chain fatty acids which improve the tear film lipid layer. Thus patients with blepharitis may benefit more from fish oils and those with dry eye from flaxseed oil. Most commercial preparations contain both fish and flax seed oil. The normal dose is 1-2 grams, or 1 tablespoon of oil, per day.
A few words of caution
Although generally safe, all dietary supplements can cause side effects. Problems include belching and flatulance, prolonged bleeding times and interference with COX-2 anti-inflammatories. Please let Dr McKellar know if you take anti-inflammatories or blood thinning agents, or get side effects.
For more information on Omega-3 see The Omega-3 Centre.