You asked

Can nutrition affect my teen's eyes?

Nutrition is incredibly important for adult's and children’s visual development, and especially with teens whose diets can often lack the vitamins and minerals required. The important vitamins for eyesight are A, C and E and the foods you will find them in are as follows:
Vitamin A 
This occurs naturally in animal sources such as beef, cod liver oil, milk and eggs 
Vitamin A occurs naturally in plant sources (and which the body converts to carotenoids) such as kale, spinach, leaf lettuce, carrots, peppers, tomatoes, tomato juice, pumpkin, sweet potatoes, broccoli, squash, watermelon, pink grapefruit and apricots.
Deficiency in vitamin A can cause night blindness, and dry eyes which can lead to night blindness. Vitamin A may also help reduce the risk of cataracts in later life.  It keeps your immune system strong and helps fight off symptoms of conjunctivitis.
Vitamin C
This is found in citrus fruits and juices, red and green peppers, grapefruit, strawberries, broccoli, kale, kiwifruit, raspberries and garlic.
Vitamin C is thought to help prevent or greatly reduce the risk of cataracts and macular degeneration in later life.
Vitamin E
This is found in whole grains, nuts such as almonds, hazelnuts, peanuts, seeds (such as sunflower seeds), leafy vegetables (such as spinach and broccoli) tomatoes, olives, kiwi, blueberries and peanut butter.
Vitamin E is thought to help maintain the health of the eye and reduce the risk of cataracts and macular degeneration in later life.
Deficiency in Vitamin E can result in the thinning of the retinas or degeneration where the inner lining of the eye becomes damaged and starts to thin. This can result in blurred vision and difficulty seeing at night.
Childhood and teenage years are the best times for developing good eating habits which should help ensure good health and optimum vision. Eating plenty of leafy green vegetables and fresh fruit is a great start!

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