... as voted second in the SKE election!

I’ve had this post in mind for a while now, and to be absolutely honest, I had a bit of head start as this was the subject of my Anatomy coursework at college (a PDF copy of which, any of you keen-beans out there can find here). It’s a topic that slots in quite nicely here, as a couple of the more recent #EyecareFAQ infographics have been about so called “degenerative eye conditions”, such as Cataracts and Age Related Macular Degeneration (AMD).

There is a wealth of information and research available out there on this very topic, the likes of which I cannot possibly hope to cover in one blog post. (Well, not without y’all falling asleep anyway!). All the usual no-brainers apply: stop smoking, limit exposure to the sun, eat healthily, etc, etc, etc, BUT! Actual scientific research has long now established that good nutrition can help guard against the development and progression of the conditions mentioned above, and perhaps many more.

Any “healthy diet” should contain a rich variety of fruits and vegetables, that we all know, as these provide vital antioxidants required to maintain good health (and in this case, good eye health), by directly disarming those pesky ‘free radicals’. Two of the main ones that pop up time and time again are the carotenoids lutein and zeaxanthin. These are most commonly found in spinach and other dark green leafy vegetables, such as kale, collards and turnip greens, as well as in orange/yellow vegetables and fruit, such as carrots (renowned for improving eyesight) and cantaloupe melon. These have been positively associated (oh-er!) with reducing the incidence of cataracts and even reversing the effects of AMD. Lycopene is another carotenoid found particularly in tomatoes – surprisingly processed tomatoes, such as canned or pureed, are richest – but also in papaya and watermelon. This one has been linked to lowering the risk of developing AMD. Bilberrys (closely related to blueberries) contain vitamin A and powerful blue-red pigments called anthocyanins, which increase levels of rhodopsin, the purple pigment that facilitates ocular blood supply.

So it would seem as far as your fruit and veg go – the more colourful the better?!

A little fact that I was unaware of, is that eye tissue contains about seven times higher concentrations of vitamin C than levels in the blood, which some might say, hints at a specific need for it? Studies have shown that the long-term (5-10 years +) intake of vitamin C, through both food and supplements, and sometimes combined with vitamin E (only from food, not supplements), reduces the risk of cataracts and may provide protection from AMD. Flavonoids and Bioflavonoids have been flagged as having some importance, as they support the action of vitamin C. Whilst low levels of zinc have been linked to AMD; low vitamin B2 (riboflavin), chromium and glutathione levels, to an increased risk of cataracts.

Something that we are always being told is good for us are the ‘Essential Fatty Acids’ – Omega 3 & 6 – and it would seem the eyes are no exception, particularly for those suffering from Dry Eye Syndrome (DES). Stock up on oily fish such as mackerel and salmon to get your fix of these beauties, whilst evening primrose oil supplements are also indicated for sufferers of DES.

Here is a handy little table summarising this information (from my aforementioned coursework): -

 

Nutrient

RNI (mg)

 

 

Some good dietary sources

Max. daily intake (mg)

 

Men

Women

 

 

Vitamin A

0.7

0.6

Liver, dairy products

1.5

b-carotene

-

-

Spinach, carrots, red peppers, mango

7

L&Z

-

-

Spinach, kale, lettuce, peas

-

Vitamin B1

1-1.4

1-0.8

Wholegrain cereals, meat, dairy products, fruit, vegetables

100

Vitamin B2

1.3

1.1

Milk, eggs, fortified cereals

40

Vitamin B3

17

13

Meat, dairy products

17 (Nicotinic acid)

500 (Nicotinamide)

Vitamin B6

1.4

1.2

Chicken, wholegrain cereals, eggs, nuts

10

Vitamin B9

0.2

0.2

Liver, green leafy vegetables

1

Vitamin B12

0.0015

0.0015

Meat, fish, dairy products

2

Vitamin C

40

40

Citrus fruit, strawberries, green leafy vegetables, liver, kidney

1000

Vitamin E

4

3

Vegetable oils

540

Selenium

0.075

0.06

Seafood, liver, brazil nuts

0.35

Zinc

5.5-9.5

4-7

Red meat, cereals, dairy products, shellfish

25

(N.B. The best source of Omega 3 & 6 is oily fish, such as mackerel and salmon.)

 

This really is only skimming the very surface of the research that has been done! Other conditions that have been demonstrated to benefit from nutritional advice include: conjunctivitis sicca, diabetic retinopathy, glaucoma, optic nerve dysfunction, night blindness, nutritional amblyopia, retinal vein occlusion and retinitis pigmentosa.

However, before you all go rushing out to your local farmer’s market to stock up on a veritable rainbow of organic fruit and veg, or to the high street health food shop to spend a month’s wages on enough nutritional supplements to make you rattle as you walk – STOP!

 

 

A varied and balanced diet should supply adequate quantities of the all the aforementioned nutrients, although many people do still choose to take supplements. However, as demonstrated by the table above (which bearing in mind is about 5 years out of date!), current UK guidelines indicate a daily intake required to maintain good health, known as the Reference Nutrient Intake (RNI). The maximum intake is the quantity that it is considered safe to consume per day without toxic effects occurring under normal circumstances.

So, before you think about making drastic changes to your diet, or introducing supplements, please consult a medical professional, either your GP or local Pharmacist; your Optometrist or friendly “all knowing” Dispensing Optician friend ;) Because sometimes too much of a good thing can actually be harmful to your health! I won’t scare or bore you in this blog, but checkout my coursework here for more information. Or, please don’t hesitate to contact me with questions or requests for more information on the official SKE e-mail – I would love to hear from you!

Special thanks to Suzannah Olivier – who I mentioned prior to this post – her book “The Essential Guide to Foods that Heal” is an absolute gem – full of cracking information on a variety of conditions that have been proven to benefit from the right dietary assistance, from acne to varicose veins – she covers it all! Absolutely blooming marvellous!!