Food for sight

Research suggests eye health can be maintained through good diet or nutritional supplements. The age-related eye disease study found that people taking certain vitamins and minerals were less likely to develop cataracts and advanced age-related macular degeneration, writes Yvonne Gordon


Vitamin A

Essential for eye health and good vision, vitamin A relates to the ability to form visual images. But we only need a small amount. When absorbed from animal sources, such as liver, other meat, oily fish, dairy products and eggs, vitamin A is called Retinol. We also take vitamin A into the diet through leafy greens, and brightly coloured fruit and vegetables, like carrots and oranges which contain antioxidants called carotenoids, some of which are converted into vitamin A.

Nutritional therapist and author of The Encyclopedia of Vitamins, Minerals and Herbal Supplements Dr Sarah Brewer says: “In the eye, vitamin A is converted into a pigment known as ‘visual purple’. When exposed to light, it absorbs photon – electro-magnetic – energy which induces a change that stimulates nerve endings in the retina. This triggers sensory messages sent to the brain to form visual images.”

Although in the UK we usually obtain enough through diet, vitamin-A deficiency, which is more common in poorer countries, can cause conditions including difficulty in adapting to dim light (night blindness) and an increased risk of cataracts. If taking vitamin A supplements, Dr Brewer warns that it is important not to go over the recommended dose, especially during pregnancy.

Vitamin C

Another important nutrient for eye health, vitamin C is not produced by the human body, unlike with animals, so we need to absorb it through diet or supplements. Scientists have recently found that nerve cells in our eyes need lots of vitamin C to function properly. Nuts, including walnuts, hazelnuts and pecans, contain vitamin C, plus most fruit, including strawberries, blackcurrants and kiwis, and vegetables, such as greens, broccoli and sprouts.

Nutritional therapist Dr Brewer, who is a GP, says: “Vitamin C is an important antioxidant – a nutrient in food which slows the cell damage caused from by-products of the body’s use of oxygen – for the eye. The level in the eye lens is 60 times more than that found in the circulation. In one study, patients taking 300mg of vitamin C daily were 70 per cent less likely to develop cataracts than similar patients not taking supplements. A good option on the market is OptiVision, a supplement from Healthspan, with an advanced formulation containing optimum levels of vitamin C.”

Research shows women who took vitamin C supplements for over ten years had 83 per cent less risk of moderate lens clouding compared with others not using vitamin C. However, it’s important to read supplement labels to ensure you’re getting 100 per cent vitamin C, as some contain added ingredients like processed sugar or artificial colouring.

Lucein

A vital component of good vision, lutein is an eye-protecting antioxidant pigment found in green, yellow and orange vegetables, plus fruits, including blueberries and grapes.

Ophthalmology professor at the University of Liverpool Ian Grierson says it’s important to increase the right antioxidant levels in the general population, as they “offer the most precise way of maintaining eye-health”. 

Lutein, naturally concentrated in the eye area called the macula responsible for fine vision, absorbs damaging blue light and protects against age-related macular degeneration (AMD) which destroys central vision.

Professor Grierson says lutein has no side effects and recommends eating 6mg daily, although average consumption is 2mg. But he adds: “Vegetables alone aren’t enough as lutein needs fat for absorption. Egg yolk is one of lutein’s main sources, which is why egg Florentine, for example, is a good meal for maintaining eye health. Spinach is high in lutein and egg yolk maximises absorption.”

However, he concedes that it’s not always easy to eat well, so a supplement like Ocuvite Complete may help. He explains: “Containing higher levels of essential micro-nutrients than diet, it provides consistent levels to protect eyes against age-related changes.” But he adds taking supplements is no excuse for bad diet.

Omega 3

There is growing evidence that food containing Omega-3 fatty acids, such as oily fish, flaxseeds and walnuts, can help maintain eye health, and arrest cataract and AMD progression in older people.

Key Omega-3 component DHA, one of the nervous system’s building blocks, has its highest concentration in the retina. But the body cannot manufacture Omega 3, which must be absorbed through diet or supplements.

Simon Madge, consultant eye surgeon Nuffield Health Hereford Hospital, says: “Since publication of the age-related eye disease study (AREDS), most eye specialists now recommend careful vitamin and antioxidant dietary supplements, which may reduce disease progression in at-risk patients. But in patients with low AMD risk, a healthy diet may provide all the supplements required.”

Mr Madge adds that stopping smoking and blood-pressure control are also essential. As with lutein, getting enough Omega 3 through diet alone can sometimes be difficult, so eye health supplements like Efalex Vision, from Efamol Ltd, which combines DHA with other antioxidants, may help.

Its technical director Peter Clough says: “Eye cells and tissues contain some of the highest levels of DHA in the body, and it is now becoming apparent that this Omega-3 fatty acid is critical to eyes’ healthy functioning as people age. Evidence suggests supplementation slows down age-related vision problems.”