Eggs are an excellent source of protein and contain many important nutrients like vitamins A, D, E, iron, zinc and more. Some research shows that certain nutrients in eggs may be beneficial for eye health. This article reviews the evidence on whether boiled eggs specifically can support eye health and vision.
Are eggs good for your eyes?
Here’s an overview of some of the key nutrients in eggs that contribute to eye health:
Lutein and Zeaxanthin
Lutein and zeaxanthin are two carotenoid antioxidants found in high amounts in egg yolks. Studies show that consuming more lutein and zeaxanthin can benefit eye health by:
– Reducing risk of age-related macular degeneration (AMD): AMD causes blurry vision and blindness in older adults. Multiple studies find that higher lutein and zeaxanthin intake cuts AMD risk by up to 41% (1, 2).
– Improving vision: Lutein and zeaxanthin improve visual performance and symptoms in those with AMD. They also reduce glare sensitivity and improve contrast vision (3, 4).
– Protecting the eyes from damage: These antioxidants filter harmful high-energy blue light. They also protect the eyes from oxidative damage caused by sunlight and normal metabolism (5).
Vitamin A
Eggs are a good source of preformed vitamin A (retinol). Preformed vitamin A is vital for:
– Converting light into signals in the eye’s retina. This allows you to see properly, especially in low light conditions (6).
– Maintaining the cornea, which is the outermost layer of the front of the eye. Vitamin A deficiency causes the cornea to become very dry and damaged (7).
– Reducing risk of night blindness. Night blindness makes it difficult to see in poorly lit environments. Those deficient in vitamin A are at much higher risk of night blindness (8).
Vitamin E
Vitamin E has antioxidant properties that are important for protecting eye health. It’s found in egg yolk.
Studies show that higher vitamin E intake is linked to a lower risk of:
– Cataracts: Cloudy areas that develop in the lens of the eye, causing blurry or hazy vision (9).
– AMD: As mentioned before, vitamin E may work together with lutein and zeaxanthin to protect against this leading cause of blindness (10).
Zinc
Zinc is concentrated in the eye, specifically the retina and surrounding tissues. It plays many essential roles in eye health, including:
– Protecting against oxidative stress and inflammation (11).
– Supporting the function of enzymes in the eye (12).
– Allowing vitamin A to be used and stored in the eye (13).
Severe zinc deficiency can even lead to vision loss and blindness if left untreated (14).
Do boiled eggs have the same benefits for eyes?
Boiling is a healthy and nutritious way to prepare eggs.
Importantly, boiling eggs does not seem to reduce their content of nutrients that are good for eye health, including:
Lutein and Zeaxanthin
According to multiple studies, lutein and zeaxanthin concentrations remain stable after boiling eggs for up to 15 minutes (15, 16, 17).
Longer boiling times may cause more nutrient loss. One study found lutein levels decreased by 5–10% when eggs were boiled for 45 minutes (18).
Vitamin A
Boiling eggs does not appear to reduce their vitamin A content. One study found no significant loss of vitamin A after boiling eggs for 15 minutes compared to raw eggs (17).
Vitamin E
One study observed no changes in vitamin E levels in eggs after boiling for 15 minutes (17).
Zinc
Zinc levels also remain unchanged with boiling according to one study. Boiling for up to 15 minutes did not affect zinc concentrations compared to raw eggs (17).
Overall, research shows lutein, zeaxanthin, vitamin A, vitamin E and zinc levels in eggs all remain relatively stable with boiling times under 15 minutes.
To maximize nutrient retention, avoid overcooking and aim for shorter cook times when boiling eggs.
Other benefits of boiled eggs
Aside from being rich in nutrients important for eye health, boiled eggs have additional benefits:
Highly nutritious
Below are the nutrients in one large boiled egg (19):
– Calories: 78
– Protein: 6 grams
– Fat: 5 grams
– Vitamin A: 5% of the RDI
– Riboflavin: 15% of the RDI
– Vitamin B12: 9% of the RDI
– Selenium: 22% of the RDI
Filling and promote fullness
Eggs are very filling. Studies show that eating eggs for breakfast reduces calorie intake later in the day and helps control hunger (20, 21).
Support weight loss
Due to their high protein and nutrient content, eggs may aid weight loss when eaten in place of refined carbs. Eating whole eggs is linked to better body composition and fat loss during calorie restriction (22, 23).
Improve heart health
Despite their reputation, eggs do not raise cholesterol or heart disease risk for most people. Eating 1–3 eggs per day is linked to improvements in heart disease risk factors (24, 25).
Easy to Cook
Boiled eggs are simple to prepare. All you need is a pot, water and eggs. The cooking process only takes a few minutes.
Potential downsides of boiled eggs
Most people can eat boiled eggs without issue. However, there are a few potential downsides to keep in mind:
– Allergy risk: Eggs are one of the most common food allergens. Symptoms include hives, congestion, nausea and wheezing (26).
– Salmonella risk: Raw and undercooked eggs may contain Salmonella bacteria, which can cause food poisoning. Boiling eggs properly kills any potential bacteria (27).
– Not suitable for certain diets: Eggs contain cholesterol and saturated fat. Those restricting these nutrients, like vegans or certain heart disease patients, may want to limit intake (28).
As long as you tolerate eggs well, boil them properly and eat them in moderation, eggs can be part of a healthy diet for most people.
Those with egg allergy or on a restricted diet should consult with a healthcare professional about egg intake.
How eating boiled eggs can support eye health
Here are some simple ways to incorporate boiled eggs into your diet to benefit eye health:
– Add chopped boiled eggs to salads. The fat will help you absorb more lutein and zeaxanthin.
– Mash boiled eggs and spread on toast. The zinc and vitamins A and E will contribute to healthy eyes.
– Make deviled eggs. Mustard contains lutein, while eggs provide antioxidants.
– Use boiled eggs in egg salad sandwiches or wraps. Egg yolk lutein helps filter blue light.
– Top avocado toast with sliced boiled eggs. The healthy fats aid nutrient absorption.
Aim for at least 1–2 boiled eggs per day as part of a balanced diet to support eye health.
Other foods good for your eyes
Besides eggs, other nutrient-dense whole foods are also excellent for eye health. Here are a few top picks:
– Leafy greens like spinach and kale have lutein and zeaxanthin.
– Brightly colored fruits like oranges contain vitamin C, an antioxidant.
– Nuts and seeds are high in vitamin E.
– Beef, pork and lamb provide zinc.
– Sweet potatoes, carrots, squash and pumpkin are great sources of vitamin A.
– Oily fish like salmon have omega-3 fatty acids that protect eyes.
A diet comprising a variety of these whole foods will ensure you get all the nutrients your eyes require daily.
Conclusion
Boiled eggs are highly nutritious and contain several vitamins and antioxidants that are great for eye health, including lutein, zeaxanthin, vitamins A and E, and zinc.
Research shows the levels of these protective nutrients remain relatively unchanged when eggs are boiled for less than 15 minutes.
Boiled eggs may also benefit eyes indirectly by promoting weight loss and improving heart health.
To fully support eye health through diet, incorporate boiled eggs along with a variety of other vitamin and antioxidant-rich foods.
Aim for 1–2 boiled eggs per day as part of a balanced diet, and be sure to boil them properly to minimize any potential risks.
Most people can safely enjoy boiled eggs as part of an overall healthy eating pattern that benefits eye health and vision.