One Egg a Day: The Cholesterol Myth Has Cracked – What Really Happens to Your Body?

Half a million people. Nearly a decade of follow-up. And a result that surprised many cardiologists: in a huge Chinese study, adults who ate an egg every day had an 18% lower risk of dying from cardiovascular disease and a 28% lower risk of dying from hemorrhagic stroke than people who rarely or never ate eggs. That is only one of several findings that have changed how nutrition science looks at the humble egg.

Hollywood actor Mark Wahlberg, known for his famous "4 a.m. club" workouts, starts every single day the same way. After his early training session, he sits down to a breakfast of scrambled eggs with turkey, hard-boiled eggs and salmon. In a video he shared with fans, he admitted that he eats the same breakfast every day, but added that he feels better every day too, as reported by PEOPLE and AOL. Many of our readers tell a similar story: once they replaced their morning pastry with eggs, they noticed they were no longer reaching for snacks by mid-morning.

So what does science actually say? Let's crack it open.

An egg for breakfast instead of a pastry

If you want to lose a few kilograms, an egg for breakfast is a better choice than a doughnut, white bread or a pastry. This was suggested by research published in the International Journal of Obesity, in which one group of overweight adults ate two eggs for breakfast and another ate a bagel-based breakfast with the same number of calories, both as part of a reduced-calorie diet. After eight weeks, the egg group lost more weight and showed a greater reduction in waist circumference.

The explanation is simple: eggs contain protein, which keeps us feeling full for longer, so we tend to eat fewer snacks during the day. In addition, eggs do not cause a rapid spike in blood sugar, which means energy is released slowly and steadily. If your mornings usually start with something sweet, it is worth reading Why is it dangerous to eat these foods for breakfast, and for more everyday diet traps, see Hello, and Fattening: Foods that Sabotage Your Diet.

One of our own authors also tested this in practice. Read how it went in With three eggs over hunger.

Eggs and inflammation in the body

Inflammation is a silent enemy of modern times. Chronic, low-grade inflammation has been linked to heart disease, diabetes and even faster aging. Eggs contain phospholipids, special fat-like compounds that, according to a review published in the journal Nutrients, may help support a healthier inflammatory balance in the body.

Research has also shown that people whose diets provide enough choline (a nutrient found mainly in the yolk that plays an important role in liver function) tend to have lower levels of certain inflammatory markers. The Greek ATTICA study, published in The American Journal of Clinical Nutrition, observed this association in more than 1,500 adults. Less inflammation is generally linked with a healthier heart, better fat metabolism and healthier aging, although diet is only one part of the picture.

Healthy fat profiles, or why eggs may be kind to your heart

For many years, nutritionists warned against the cholesterol in egg yolks. Today we know the story is more complicated. There is "good" cholesterol (HDL) and "bad" cholesterol (LDL), and the cholesterol we eat does not translate directly into the cholesterol in our blood. Some studies suggest that eggs may even help raise HDL, the type that helps carry excess cholesterol away from the blood vessels.

A 2025 study from the University of South Australia, published in The American Journal of Clinical Nutrition, went one step further: when two eggs a day were eaten as part of a diet low in saturated fat, LDL cholesterol did not rise. According to the researchers, saturated fat, not the cholesterol in eggs, is the main factor to watch. Experts at Cedars-Sinai agree that it is mainly the bacon, sausage and butter served alongside eggs that deserve more attention.

The China Kadoorie Biobank study, published in the journal Heart, followed more than 500,000 adults aged 30 to 79, in collaboration with the University of Oxford. Those who ate up to one egg a day had an 18% lower risk of cardiovascular death and a 28% lower risk of death from hemorrhagic stroke compared with those who rarely ate eggs. It is important to note that this was an observational study: it shows an association, not proof that eggs alone cause the benefit.

Eggs for muscles: food after exercise

When you exercise, your muscles need building material to recover. Eggs are one of the best natural options, because they contain all nine essential amino acids (protein building blocks the body cannot make on its own). Among them is lysine, which is important for muscle repair and tissue maintenance.

The World Health Organization (WHO) estimates that adults need about 30 mg of lysine per kilogram of body weight per day. For a person weighing 70 kg, a single large egg covers roughly a fifth of that requirement, and a two-egg portion comes close to half.

The immune system and the thyroid

One thing we often overlook is that a single large egg provides around a quarter of the daily value for selenium. According to the U.S. National Institutes of Health (NIH), selenium is a mineral that supports the normal function of the immune system and plays a role in thyroid hormone metabolism.

During the cold and flu season, this makes eggs a particularly valuable addition to the menu. An adequate selenium intake is one of many factors that help the immune system do its job, alongside sleep, physical activity and a varied diet rich in fruit and vegetables.

Energy throughout the day

An egg is a true energy package in a small shell. One large egg provides a meaningful share of the daily requirement for vitamin B2 (riboflavin). As explained by the NIH Office of Dietary Supplements, this vitamin helps the body turn food into energy. So if you eat an egg in the morning, you help support steadier energy levels throughout the day, without the dips that often follow sugary drinks or pastries.

Healthier-looking skin, hair and nails

The B vitamins found in eggs (B2, B5 and B12) play an important role in maintaining normal skin, hair and vision. The yolk is also rich in biotin, a vitamin often associated with nail health. One cooked egg provides about a third of the daily value for biotin, according to the NIH biotin fact sheet.

Several small studies have suggested that people with brittle nails may notice improvement after several months of adequate biotin intake, although the evidence is still limited. A useful nutritionist's tip: always eat eggs cooked. Raw egg white contains avidin, a protein that binds biotin and prevents its absorption, while cooking neutralizes it and also reduces the risk of Salmonella.

Eggs as brain food

Nutritionists often call eggs "brain food", and this is no coincidence. The yolk contains choline, which is essential for the function of nerve cells and for the production of acetylcholine, a messenger that carries signals in the brain. One large egg provides about 150 mg of choline, roughly 25% of the daily value, according to the NIH choline fact sheet.

Research suggests that people with low choline intake may be more likely to experience difficulties with memory and concentration. A 2025 study from the Rush Memory and Aging Project in the United States, published in The Journal of Nutrition, followed more than 1,000 older adults and found that those who ate at least one egg per week had a 47% lower risk of developing Alzheimer's dementia than those who rarely ate eggs. Choline accounted for about 39% of this association. The researchers stress that the study shows a link, not cause and effect.

In addition to choline, egg yolks contain small amounts of omega-3 fatty acids (especially DHA), as well as lutein and zeaxanthin, which support eye health. Eggs from hens fed omega-3-rich feed contain noticeably more of these healthy fats.

Folk wisdom about eggs

In the countryside, eggs were always considered "food for strength". Grandmothers used to say that a patient who was recovering should eat an egg to regain their strength. Eggs were also often given to children for breakfast because people believed they "feed the head". Today we know this belief has a real basis, since choline and high-quality protein genuinely support the brain.

During the Second World War, eggs were so precious that in Britain fresh eggs were strictly rationed, and families often received only one fresh egg per week, with dried egg powder as a substitute, as described by the Imperial War Museums. This shows how important eggs were as a source of nutrients when food was scarce.

What about the risks?

Of course, the question arises: does one egg a day increase the risk of high cholesterol and heart disease? Older studies hinted at this, but today we know that eggs on their own are not the main culprit. A bigger problem is the overall pattern of an unhealthy diet: plenty of processed food, a lot of saturated fat and too little physical activity. For an overview of foods that deserve more caution than eggs, see 5 Foods That Shorten Your Lifespan.

In 2020, the American Heart Association (AHA) published a science advisory in the journal Circulation stating that healthy adults can include up to one whole egg a day as part of a heart-healthy diet. The advisory also notes that people with high LDL cholesterol, diabetes or a higher heart disease risk should be more mindful of their total dietary cholesterol and discuss their egg intake with their doctor or a registered dietitian. People with an egg allergy should, of course, avoid eggs altogether.

A small package with a big impact

The egg is one of the most complete foods we know. In a small shell, you get high-quality protein, vitamins, minerals, healthy fats and antioxidants. Eating one egg a day as part of a varied diet can support your heart health, memory, immune system, and even the health of your skin, hair and nails.

The best way to enjoy them? Boiled, poached or scrambled with vegetables, served with wholegrain bread rather than with bacon and sausages. And best of all, eggs are inexpensive, widely available and can be prepared in a hundred different ways.

Although the cholesterol myth frightened us for a long time, today we know that for most healthy people, one egg a day is not a threat but an opportunity to give your body what it truly needs.