In a world where there's a pill for everything, ocular supplements raise the question: should you or shouldn’t you?
The shelves of pharmacies are packed with little glass bottles and plastic boxes of supplements for every human malady. A sub-section of these capsules and pills claim to improve or protect ocular health. This post looks at which eye conditions benefit from which supplements as well as when you could be wasting your money or jeopardising your health.
Do you need supplements to maintain healthy vision?
As long as you have a varied diet that includes fruit and vegetables and you don’t have a diagnosed deficiency that increases your risk of disease, supplements are rarely necessary.
If you’re eating plenty of green leafy vegetables and coloured fruits and vegetables (e.g. tomatoes, root vegetables and capsicum) you are unlikely to see any benefits from taking an ocular supplement unless you have macular degeneration or dry eye disease.
What about macular degeneration?
This is one of the few eye diseases where an approved supplement recommended by your doctor or optometrist can actually make a difference.
A large, long-term study in the US called the Age-Related Eye Disease Study (AREDS) found that certain micro-nutrients slowed down the progression of macular degeneration in a large percentage of people.
Vitamins (C and E), minerals (zinc and copper) and antioxidants (lutein and zeaxanthin) found in tomatoes and other coloured vegetables all contributed a benefit to people with macular disease.
But the study noted that no supplement can prevent you from getting the disease in the first place.
Each daily dose of the AREDS-based formula contains the following:
- 500 mg vitamin C
- 400 IU vitamin E
- 80 (40) mg zinc*
- 2 mg copper
- 10 mg lutein
- 2 mg zeaxanthin
*In Australia, where recommended daily doses of zinc are lower than some other countries, the formula is slightly modified to provide the appropriate dose of zinc.
Always consult your doctor or optometrist before beginning any vision supplement.
Dry eyes and supplements
Dry eye disease is a complex and multifactorial condition. Many sufferers rely on dry eye drops to bring relief even though this often provides only symptomatic relief. The underlying cause of dry eye disease can often be nutritional, and if so, addressing nutrition can be an effective treatment.
Omega 3s are your best friend when it comes to dry eye disease. They function in several different ways to improve signs and symptoms of this condition. Omega 3 oils supplements are well known for causing the side effect of upset stomach if taken in excess. There are ways to bypass this problem but even with the normally well-tolerated dose contained in a daily capsule, you can get an improvement.
Probiotics are also very useful in managing a range of illnesses including dry eye disease. Talk to your dry eye practitioner about what supplements may improve your dry eye symptoms.
What about other eye diseases?
Should you be taking supplements for other eye problems, just in case? Probably not. The ARED studies also looked at any possible links between dietary nutrients and eye diseases such as cataract and glaucoma. But they found no conclusive evidence of any benefit.
Our advice is, unless you have a clear medical need for a supplement or you suffer from macular degeneration or dry eye disease, save your money.
Can supplements do any harm?
Actually yes. Apart from the damage to your hip pocket, all ocular supplements have side effects. Most of these are mild and can range from digestive upset to headaches and skin problems. But there are some very concerning side effects associated with high doses of certain supplements:
The original AREDS-based formulation for macular degeneration contained beta-carotene – a well-known antioxidant found in coloured fruits and vegetables and green leafy vegetables. It is converted to vitamin A in the body.
But clinical studies have shown a convincing link between beta-carotene and the risk of lung cancer in smokers. The Cancer Council cautions people against taking high levels of beta-carotene, especially if they smoke.
The current AREDS-based supplement for macular degeneration does NOT contain any beta-carotene. It’s still important to discuss taking this supplement with your GP and optometrist.
Vitamins C and E
High doses of vitamin C can cause stomach upset and diarrhoea.
High doses of vitamin E can interfere with your blood’s clotting ability. Doses over 44 IU per day should be avoided in anyone with diabetes or a heart condition. Even over-the-counter vitamin supplements should be discussed with your doctor in case they might interfere with other medications you are taking.