Eggs have been part of human diets for thousands of years, and with good reason. They’re cheap, versatile, and pack an impressive nutritional punch for something that weighs about 50 grams. Yet few foods have been as controversial. For decades, we were told to avoid eggs because of their cholesterol content. Then the science shifted, and suddenly eggs were back on the menu.

So what’s the truth? Are eggs actually good for you, or should you be limiting them? I’ve looked at the research, and the picture is more nuanced than either extreme suggests.

What makes eggs so nutritious?

A single large boiled egg (roughly 50 grams) contains approximately 77 calories, 6 grams of protein, and 5 grams of fat. But the real story is in the micronutrients. Eggs contain meaningful amounts of:

Vitamin A: 244 IU (important for vision and immune function)
Vitamin D: 17.5 IU (one of few natural food sources)
Vitamin B12: 0.6 mcg (essential for nerve function)
Riboflavin (B2): 0.2 mg (helps convert food to energy)
Folate: 23.5 mcg (crucial during pregnancy)
Choline: 126 mg (most people don’t get enough)
Selenium: 15.8 mcg (antioxidant mineral)
Phosphorus: 95.5 mg (bone health)

Eggs are considered a “complete” protein source because they contain all nine essential amino acids in roughly the proportions our bodies need. The bioavailability of egg protein is exceptionally high, meaning your body can actually use most of what you eat, unlike some plant protein sources where absorption is lower.

Worth noting: the yolk contains most of the fat-soluble vitamins (A, D, E, K) and all the choline, while the white is mostly protein. If you’re only eating egg whites, you’re missing out on much of the nutrition.

1. Eggs provide high-quality protein that’s easy to absorb

The protein in eggs has a biological value of 100, which scientists use as the reference standard against which other protein sources are measured 1. This means that nearly all the protein you consume from eggs can be used by your body for building and repairing tissues.

For comparison, beef has a biological value around 80, and most plant proteins score lower still. This makes eggs particularly valuable for:

Older adults trying to maintain muscle mass
Athletes recovering from training
Anyone on a budget who needs affordable protein
Vegetarians who include eggs in their diet

One large egg provides about 6 grams of protein, roughly 13% of an adult’s daily requirement. Having two eggs at breakfast gives you a solid protein foundation that many people struggle to achieve with typical breakfast foods like toast or cereal.

My take: If you’re looking for an affordable, highly digestible protein source, eggs are hard to beat. The science on protein quality is quite solid here.

2. Lutein and zeaxanthin protect your eyes (yes, this is the “bright future” part)

Here’s where eggs become genuinely interesting. Egg yolks are one of the best dietary sources of lutein and zeaxanthin, two carotenoid pigments that accumulate in the macula, the central part of your retina responsible for sharp, detailed vision.

These compounds act as a natural filter against high-energy blue light and help neutralise free radicals that can damage photoreceptor cells over time. Given how much time most of us spend staring at screens, this matters more than it used to.

A randomised controlled trial published in the American Journal of Clinical Nutrition found that eating one egg daily for five weeks significantly increased blood levels of both lutein and zeaxanthin 2. More importantly, these nutrients from eggs appear to be more bioavailable than from supplements or vegetables. The fat in the yolk helps your body absorb them.

Research suggests that higher intakes of lutein and zeaxanthin are associated with reduced risk of:

Age-related macular degeneration (AMD)
Cataracts
General eye fatigue

For more on supplements that support eye health, see our article on lutein benefits and side effects, or our overview of foods good for eyesight.

Reality check: While the mechanism is plausible and early research is promising, we don’t yet have definitive proof that eating more eggs prevents eye disease in healthy people. But the evidence is strong enough that I’d consider it a reasonable bet, especially since eggs have other benefits too.

3. Eggs can raise HDL (the “good” cholesterol)

Not all cholesterol is the same. High-density lipoprotein (HDL) is often called “good cholesterol” because it helps transport excess cholesterol from your arteries back to your liver for disposal. Higher HDL levels are consistently associated with lower cardiovascular risk in epidemiological studies.

Several studies have found that eating eggs regularly can increase HDL levels. In one study, consuming two eggs daily for six weeks raised HDL by 10% 3.

The relationship works like this: your liver produces most of your blood cholesterol (roughly 70-80%), and it adjusts production based on what you eat. When you consume more dietary cholesterol, most people’s livers simply make less. This is why eating cholesterol-rich foods doesn’t automatically raise blood cholesterol levels.

The catch: About 25-30% of people are “hyper-responders” whose cholesterol levels are more affected by dietary intake. If you have familial hypercholesterolaemia or known cholesterol issues, you should discuss egg consumption with your doctor rather than assuming the general guidelines apply to you.

4. Eggs are one of the best sources of choline

Choline is an essential nutrient that most people have never heard of, yet surveys consistently show that the majority of adults don’t consume enough 4. Your body needs choline for:

Building cell membranes (it’s a component of phosphatidylcholine)
Producing acetylcholine, a neurotransmitter crucial for memory and muscle control
Methylation reactions that affect DNA expression
Transporting fats out of the liver

One large egg contains about 125 mg of choline, primarily in the yolk. The recommended daily intake is 550 mg for men and 425 mg for women, so two eggs provide roughly half of what you need.

Adequate choline intake during pregnancy is particularly important for foetal brain development. It’s also relevant for anyone concerned about cognitive function as they age, though the evidence for supplementation preventing dementia remains preliminary.

In practice: If you eat eggs regularly, you’re probably meeting your choline needs. If you avoid eggs and don’t eat much liver (the other rich source), you might want to pay attention to this nutrient.

5. Eating eggs doesn’t increase cardiovascular disease risk for most people

This is the big one, and it’s where the science has evolved considerably.

For decades, eggs were vilified because of their cholesterol content (about 186 mg per large egg). The thinking was straightforward: high blood cholesterol increases heart disease risk, eggs contain cholesterol, therefore eggs must increase heart disease risk.

But the body is more complex than that. A large meta-analysis of 17 studies involving nearly 260,000 participants found no significant association between eating one egg daily and increased risk of coronary heart disease or stroke 5. The British Heart Foundation now states that eggs can be part of a healthy diet.

The 2015 US Dietary Guidelines removed the previous 300 mg daily cholesterol limit, acknowledging that dietary cholesterol has less impact on blood cholesterol than previously thought. The NHS also notes that there’s no recommended limit on egg consumption for most healthy adults 6.

Worth noting: The relationship between eggs and cardiovascular health may differ for people with diabetes. Some studies have suggested a modest increased risk in this group, though the evidence is mixed and confounded by other dietary factors. If you have type 2 diabetes, it’s worth discussing your egg intake with your healthcare provider.

6. Eggs contain vitamin D, which many people lack

Vitamin D deficiency is surprisingly common, particularly in countries with limited sunlight during winter months. Eggs are one of the few foods that naturally contain vitamin D, with each egg providing about 17.5 IU (or roughly 1 mcg).

That might not sound like much given the recommended daily intake of 10-20 mcg, but it adds up. And unlike many fortified foods, the vitamin D in eggs comes in a form your body readily uses.

Vitamin D is essential for calcium absorption, bone health, and immune function. Some research suggests it may also play a role in mood regulation and muscle strength, though these benefits are less firmly established.

Eggs from hens raised with access to sunlight or fed vitamin D-enriched diets can contain substantially more. Some speciality eggs claim 2-3 times the vitamin D of conventional eggs, though you’ll pay a premium for them.

My honest take: Eggs alone won’t solve a vitamin D deficiency, but they contribute to your overall intake in a way that most foods don’t. Combined with modest sun exposure and possibly a supplement during winter, they’re part of a reasonable strategy.

What about omega-3 enriched eggs?

You’ve probably seen eggs marketed as “omega-3 enriched” at higher prices. These come from hens fed diets containing flaxseed, fish meal, or algae. They do contain more omega-3 fatty acids than conventional eggs, though typically less than you’d get from eating oily fish.

A standard egg has about 30-50 mg of omega-3s, while enriched varieties might contain 100-200 mg. For context, a serving of salmon provides around 1,500-2,000 mg.

If you don’t eat fish and want to boost your omega-3 intake, enriched eggs offer a modest benefit. But if you’re already eating fish oil supplements or oily fish weekly, the extra cost probably isn’t justified.

How many eggs can you eat?

This question doesn’t have a definitive answer because it depends on your overall diet, health status, and individual cholesterol response. However, research generally suggests:

For healthy adults, eating 1-3 eggs daily appears safe and may have benefits
The overall quality of your diet matters more than focusing on any single food
If you have existing cardiovascular disease, diabetes, or familial hypercholesterolaemia, you should seek personalised advice

The Mayo Clinic suggests that most healthy people can enjoy up to seven eggs per week without increasing their heart disease risk 7. But this assumes the rest of your diet is reasonably healthy. Frying eggs in butter every morning alongside processed meat is a different proposition from having poached eggs with vegetables.

Practical tips for including eggs in your diet

If you’re looking to get more eggs into your meals:

Hard-boiled eggs keep well in the fridge for up to a week and make an easy grab-and-go snack
Poaching or boiling avoids adding extra fat from frying
Scrambled eggs with vegetables can turn breakfast into a more nutrient-dense meal
Eggs baked into dishes like frittatas or shakshuka make satisfying dinners
Egg salad (with sensible amounts of mayonnaise) works for lunches

One thing to watch: what you eat with your eggs matters. Two eggs alongside a pile of bacon, sausages, and white toast is a different nutritional picture than two eggs with wholegrain toast and avocado.

Summing up

Eggs are a genuinely nutritious food that’s been unfairly demonised due to outdated concerns about dietary cholesterol. The current evidence suggests that for most healthy people, eating eggs regularly:

Provides high-quality, affordable protein
Delivers lutein and zeaxanthin for eye health
May improve HDL cholesterol levels
Supplies hard-to-get choline
Doesn’t increase cardiovascular disease risk

Are they a miracle food? No, such things don’t exist. But they’re a solid, versatile, and affordable addition to most diets. The main caveat is for people with specific conditions like familial hypercholesterolaemia or diabetes, who should discuss their individual situation with a healthcare provider.

For related reading on nutrition and supplements, you might also be interested in our articles on DHA (another nutrient found in enriched eggs) or vitamin A.

References

Layman DK, Rodriguez NR. Egg protein as a source of power, strength, and energy. Nutr Today. 2009;44(1):43-48.
Goodrow EF, et al. Consumption of one egg per day increases serum lutein and zeaxanthin concentrations in older adults. J Nutr. 2006;136(10):2519-24.
Mutungi G, et al. Eggs distinctly modulate plasma carotenoid and lipoprotein subclasses in adult men following a carbohydrate-restricted diet. J Nutr Biochem. 2010;21(4):261-7.
Zeisel SH. Choline: critical role during fetal development and dietary requirements in adults. Annu Rev Nutr. 2006;26:229-50.
Rong Y, et al. Egg consumption and risk of coronary heart disease and stroke: dose-response meta-analysis of prospective cohort studies. BMJ. 2013;346:e8539.
NHS. Eggs in your diet. https://www.nhs.uk/live-well/eat-well/food-types/eggs-nutrition/
Mayo Clinic. Eggs: Are they good or bad for my cholesterol? https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/expert-answers/cholesterol/faq-20058468