Can poor nutrition cause vision problems?
Vision problems can be caused be various factors, but poor nutrition is one that is more easily fixed than others.
Deficiencies in the following nutrients can cause noticeable, problematic symptoms in the eyes:
- Vitamin D
- Vitamin A
- Vitamin C
- Vitamin E
- Vitamin B12
Read on for a closer look at how these nutrients affect your eyes, as well as some advice on how you can ensure you don't become deficient in any of them.
Can vitamin D deficiency affect eyesight?
Dry eyes could be a sign of vitamin D deficiency.1 When the eyes become dry as a result of low vitamin D levels, it may also become more difficult to produce tears.
The eyes might feel gritty, sore or itchy and vision could become blurred. The eyes may also be more sensitive to light than normal.
If you are experiencing these symptoms of dry eyes, it may help to increase your intake of vitamin D. We get much of this nutrient from the sun, so spending more time outdoors can help with this. Vitamin D is also found in eggs, mackerel, milk and salmon.
Vitamin D is known to be anti-inflammatory in its effects which may explain why it helps dry eyes. It could also have a protective effect on tear film – an extremely thin layer of fluid that sits on the surface of the eyes and lubricates the inner eye.2
Although low vitamin D can contribute to dry eyes, it's important to bear in mind that other things, such as using contact lenses frequently, being over 50 and spending long periods looking at phones and computers, can also contribute to the problem.
Is vitamin A good for your eyes?
Vitamin A is important for maintaining healthy corneas (the transparent outer surface of the eyes). This means a deficiency could be another contributing factor to dry eyes, as well as the inability to produce tears.
Vitamin A is also important in helping us to see at night as it contains a component called rhodopsin – a protein that helps us see in low lights. As such, another indication of low vitamin A is night blindness. In severe cases (where there is a lack of vitamin A in the diet for an extended period of time) this may develop into complete blindness. This situation is very rare, however, as it is usually possible to get at least some vitamin A from our diet.
There is also some evidence to suggest that vitamin A could help to protect against Age-Related Macular Degeneration (AMD)3 and cataracts, both of which can lead to a deterioration in vision over time.4 It is possible that a deficiency in these nutrients also increases the likelihood of developing such problems.
So, vitamin A is very important for eye health. If you want to get more vitamin A into your diet, it can be found in sweet potato, tuna, hard goat's cheese and more.
Is vitamin C good for your eyes?
Vitamin C has several important roles, including helping to protect cells and supporting blood vessels in the eyes. Nerve cells in the eye also need vitamin C in order to function properly.5 On top of this, vitamin C is required to build connective tissue like collagen which is found in the cornea.6
As vitamin C is so important for the eyes, a deficiency can cause problems here including, once again, dry eyes. Vitamin C supplements, on the other hand, have been shown to reduce the prevalence of dry eyes.
There is also research to suggest that conditions like AMD and cataracts can worsen more quickly when an individual fails to get enough vitamin C through their diet, plus, a deficiency could increase the risk of developing the problem in the first place.7
Vitamin C is, of course, widely accessible through our diet. Blackcurrant, for example, is a dark purple berry with an extremely high vitamin C content – four times higher than oranges, in fact!
Blackcurrants also contain catechins and other beneficial flavonoids, and both anthocyanins and proanthocyanins. These are powerful antioxidants with anti-inflammatory properties, but are also useful for strengthening blood vessels and improving blood flow.
Is vitamin E good for your eyes?
Vitamin E deficiency can cause various symptoms, including reduced quality of vision and, over time, loss of vision. This is because light receptors in the retina can become damaged.
Vitamin E is an antioxidant so may also protect against oxidative damage. As this is associated with degenerative diseases like AMD, getting enough vitamin E could lower the risk of developing this problem.8
The retina is particularly susceptible to oxidative damage because it uses up a lot of oxygen, it contains a high concentration of polyunsaturated fatty acids, and it is exposed to visible light. What the eye needs is protective pigments laid down in a nice thick layer as this absorbs and filters damaging light. Fortunately, these pigments are found in dietary antioxidants, such as vitamin E, which are contained in healthy foods such as vegetables.
It is actually quite rare to become deficient in vitamin E as a result of poor diet as this nutrient is so widely available. Foods including nuts and seeds, fish and vegetables like spinach and broccoli all contain vitamin E.
Vitamin E deficiency is most likely to occur as a result of an underlying medical condition.
Can B12 deficiency cause vision problems?
Vision problems, such as blurred or distorted vision, can occur when there is not enough vitamin B12 in the diet. Although rare, this is caused by damage to the nervous system. This makes it more challenging for the brain to relay messages to the eyes, thus resulting in poor vision.9
A supplement can usually help to reverse vision problems that are the result of a B12 deficiency. However, to prevent the problem from developing in the first place, foods including tofu, fish, cheese and milk should regularly be consumed.
How does low zinc affect the eyes?
Noticeable quantities of zinc are found in the eyes meaning a deficiency can cause problems such as poor vision.
Zinc is another nutrient that has been shown to reduce the chance of developing AMD10 so, once again, if you don't get enough you could be more at risk of this problem.
Zinc also protects the eyes from oxidative damage so it is thought to play a part in protecting the eyes from cataracts too.
Pumpkin seeds, quinoa, legumes and cashew nuts are just a few examples of foods containing zinc. For a little additional zinc, you could try Balance Mineral Drink which contains this nutrient in combination with vitamin D, magnesium and more. This should keep your energy up, as well as helping to support your overall nutrient levels.