An egg a day doesn’t seem to prevent or promote memory disorders. However, an egg a day may otherwise be beneficial for brain function, write the University of Eastern Finland’s nutrition researchers in Frontiers for Young Minds, a scientific journal aimed at children.
The idea for the article for children came from a study published as part of Doctoral Researcher Maija Ylilauri's doctoral dissertation, the results of which were originally published in the American Journal of Clinical Nutrition.
“I was told that researchers can offer stories about their articles to a scientific journal for children, so I sent in an abstract and they got interested,” Ylilauri says.
Frontiers for Young Minds is aimed at school children, and it features scientific articles that have been adapted for a child audience. Just like in real a scientific journal, the quality of an article is ensured by peer review, but in this journal, review is carried out by children.
“We had a 12-year-old reviewer whose feedback was very sympathetic. For example, we switched some difficult words for easier ones based on their comments.”
Many people ask whether eggs are a good or a bad food and whether egg intake should be restricted in some way.
Maija Ylilauri
Väitöskirjatutkija
Eggs are a better source of nutrition than their reputation suggests
In her doctoral dissertation, Ylilauri examines the association of egg, milk, meat and fish consumption with the risk of memory disorders.
“We have also separately examined fermented and non-fermented dairy products, as well as processed and unprocessed meats.”
The findings on eggs seemed like a good and concrete topic to be explained to children. In her work as a dietician, Ylilauri has noticed that many have questions about whether eggs are good for health.
“Many people ask whether eggs are a good or a bad food and whether egg intake should be restricted in some way because of the cholesterol contained in them. However, there are no specific restrictions on eggs for healthy people.”
The egg yolk is rich in cholesterol, but in most cases, it has little effect on blood cholesterol levels. Among carriers of the so-called APOE4 genotype, on the other hand, cholesterol from diet and eggs may increase blood cholesterol levels more easily. According to nutrition recommendations, people with arterial diseases should not eat more than 3–4 egg yolks per week.
However, eggs contain many good nutrients, such as high-quality protein, vitamins, good-quality fat and choline, the intake of which Ylilauri and fellow researchers in the group have linked to a lower risk of dementia.
Those eating more eggs did well in tests
“Maybe you are wondering how on Earth eggs and memory are connected. That is a good question,” writes Ylilauri in her scientific article for children, with Associate Professor Jyrki Virtanen providing support for the writing process.
There is currently no cure for memory disorders, but studies suggest that a healthy diet, among other things, can reduce the risk of illness.
“Less is known about the effects of individual foods on memory and brain health. As far as we know, the association of eggs with memory disorders has not been studied by anyone else before.”
Answers were sought in the data of the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD). At the beginning of the study, researchers analysed the dietary habits, lifestyles and health of approximately 2,500 men living in eastern Finland. During a follow-up of 30 years, some of them developed a memory disorder.
“In this study, the consumption of eggs or the dietary intake of cholesterol did not seem to be associated with the risk of a memory disorder, not even in men with the APOE4 genotype. In this sense, eggs didn’t hurt, but they didn’t help, either.”
However, men who ate more eggs did slightly better in various tests measuring cognitive function, which they took four years after the initial measurements of the study.
“Eating eggs could therefore be beneficial to brain function, but further research is needed. Based on this study, it is at least safe to eat eggs as part of a healthy diet.”
But how many eggs can be eaten?
“In this study, an egg a day was fine. It is not possible to say anything about a larger number, because there weren’t that many heavy users of eggs in this study,” Ylilauri says.
Brain exercise for the researcher
According to Ylilauri, it was refreshing to translate the study into a language that can be understood by children.
“It was fun to write about research in a more creative manner and without strict constraints. Usually, scientific journals have a specific format for articles, but here it was possible to let loose a bit.”
“However, since English is not my native language, it was a bit challenging to grasp what kind of vocabulary is understandable to English-speaking children. I really had to think about how to talk about a topic and concepts that children may not even have heard of before. But in the end, it turned out to be good exercise for the brain.”
Ylilauri has also recently finished another writing project of a larger scale: the manuscript of her doctoral dissertation is ready, and the results will likely be publicly examined in the upcoming months.
Read more:
Ylilauri, M. & Virtanen, J. (2022)Are Eggs a Superpower for the Brain and Memory?. Front. Young Minds. 10: 697754. doi: 10.3389/frym .2022 .697754
Ylilauri, M. P. T., Voutilainen, S., Lönnroos, E., Mursu, J., Virtanen, H. E., Koskinen, T. T. et al. 2017. Association of dietary cholesterol and egg intakes with the risk of incident dementia or Alzheimer disease: the Kuopio Ischaemic Heart Disease Risk Factor Study. Am. J. Clin. Nutr. 105:476–84. doi: 10.3945/ajcn.116.146753