AND Is it possible that eating eggs protects the brain. It had already emerged in research laboratories and now extensive work, just published in The Journal of Nutrition, tries to quantify the benefits: consuming two to four a week would reduce the risk of developing Alzheimer’s by 20 percent. What is certain is that eggs are a treasure of nutrients and one of the healthiest, economical, versatile and sustainable protein sources. In Italy we continue to be suspicious, thinking about thehypercholesterolemia.
The doubt is legitimate, because the yolk contains 200-210 milligrams of cholesterol, three times more than a sausage. Except that cholesterol assimilated through food accounts for about a fifth of the total levels in the blood, while four fifths are produced by the body itself. And it is precisely this endogenous fabrication that is increased by one diet overflowing with saturated and trans fats, therefore based on red meat, fatty and mature cheeses, cured meats, butter, chips and ultra-processed foods. An egg, however, has just 1.6 grams of saturated fat (compared to 5-8 in a pound of ribeye).
Cholesterol? Eggs acquitted
What has eliminated any ban on dietary cholesterol are the new recommendations of the Italian Society of Human Nutrition (Sinu). Previously, the maximum recommended daily intake was 300 milligrams, but no longer in the 2025 guidelines. As stated, that limit has been eliminated “in light of the studies and related meta-analyses which have highlighted the relative lack of importance of cholesterol intake compared to that of saturated fats”. It is now clear that there is no relationship between a normal consumption of egg yolks and an increase in LDL cholesterol, that is, low-density lipoproteins that cause the accumulation of plaques in the arteries. The eggs have been rehabilitated and, among their advantages, there are those for the brain. Not that there is direct evidence of cause and effect in recent research.
The study is observational, it records data and phenomena describing how, on a sample of people, aassociation between egg consumption and decreased incidence of Alzheimer’s. Obviously, nutrition as a whole also applies. The participants were 39,498 Seventh-day Adventists, followed for about 15 years: the Protestants of the religious group born in the mid-nineteenth century in the United States are often monitored in nutritional research because many of them follow healthy lifestyles. The same researchers who examined them work on Loma Linda Universitya private university in California that is part of the educational system of the Adventist church.
Nutrients for neurons
Given these premises, it must be recognized that an egg contains nutrients that are fundamental for the functioning and protection of the brain. Meanwhile, it provides over 6 grams of protein, a quantity that experts consider high in relation to the 70 calories. Quality also counts. Proteins, the building blocks of our body (including neurons), are composed of various combinations of twenty amino acids, nine of which must be obtained through food. Eggs contain all nine, making them a complete protein source. In particular, among the amino acids there is tryptophan, which is used to synthesize serotonin, known as the good mood molecule, and melatonin, which induces sleep. If the proteins are concentrated mainly in the egg whites, the other nutrients are found in the yolk. Vitamins B9 (or folate) and B12 (or cobalamin) stand out.
In a work from 2025 (su Scientific Reports), the researchers noted that lower plasma levels of B vitamins are associated with a greater risk of cognitive impairment, while the higher ones show a protective effect. The Yolk also gives vitamin Dwhich acts in multiple brain areas, so much so that its deficit can compromise attention, memory and learning, as converging studies show. It is true that vitamin D is produced mainly by our skin exposed to sunlight, but 10-20 percent of what is necessary is still assimilated through food. The praise of eggs continues with the minerals they provide: zinc, with antioxidant properties, and iron, which is used for the synthesis of serotonin and the key substances of the reward system: dopamine, which pushes us to desire something, and opioids, which flood us with pleasure.
Sustainable food
And the old story that eggs are bad for the liver? Not only is it unfounded, but the yolk and egg white provide useful substances for the proper functioning of liver cells, such as methionine and choline, the deficiency of which can promote the accumulation of fat (hepatic steatosis). Among other things, choline, of which eggs are a mine, is important for muscle control, metabolism, the nervous system, mood and memory. It makes no sense to demonize a food that has been part of the human diet for millennia. Sustainable to boot. The total of greenhouse gases, climate-altering, which derive from the production of eggs is a little higher than legumes but much lower than beef. In other words, if eggs partially replaced steaks and sausages, they could be among the foods that contribute to curbing emissions (and the consequent global warming) linked to the food system. Out of respect for animals, packages indicating that they come from caged hens should be discarded. It is the code printed on the shell that gives a series of information: the number at the beginning refers to the type of farming, starting from 0 which indicates organic farming up to 3, the worst.
Good to the last shell
Soft-boiled, hard-boiled or scrambled? How to bring egg yolks and egg whites to the table in a healthy way
Cooking eliminates any pathogenic bacteria (the danger of raw eggs) and makes the egg white more digestible. The yolk, on the other hand, is digested better and retains a greater amount of vitamin B12 when it is liquid, just like in a soft-boiled egg, i.e. left in boiling water for three minutes. Hard-boiled or poached eggs are also fine, of course. And even in a slimming diet there is that little bit of fat that adds flavor without exploding calories: fried or scrambled egg with a drop of oil in a non-stick pan. And the egg white omelette? It is protein and fat-free, but most of the nutrients are found in the yolk.
The menu
An example of a healthy dinner? One or two eggs, a salad, wholemeal or semi-wholemeal bread, fruit, extra virgin olive oil for dressing and water to drink.
Eggs have the advantage of promoting a sense of satiety also by virtue of the protein content.
The control
There is a method to check if an egg is edible at home. It is immersed in cold water and salt: if it is fresh, it settles on the bottom horizontally, otherwise it floats.
Eliana Liotta (photo by Carlo Furgeri Gilbert).
Eliana Liotta is a journalist, writer and science communicator. On iodonna.it and on the main platforms (Spreaker, Spotify, Apple Podcast and Google Podcast) you can find his podcast series The good that I want.
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