Eating 1 egg per week linked to lower Alzheimer's risk, study finds

• A study finds that eating eggs is associated with a reduced risk of developing Alzheimer’s disease.
• Using brain autopsies, the scientists also showed that those who ate eggs more regularly had less protein buildup in the brain associated with Alzheimer’s.
• The researchers conclude that this link may be due to eggs’ choline and omega-3 content.

Eggs have been a dietary staple since before humans evolved to be humans. Although they are packed with nutrients, relatively cost-effective, and easy to source, they have been the subject of much controversy in the health and wellness domain over the years.

A study whose results appear in The Journal of Nutrition, however, may help reestablish their good reputation. 

According to the authors, eating one egg per week was associated with a 47% reduction in Alzheimer’s risk compared with eating eggs less than once each month. 

They also showed that those eating eggs had a reduced buildup of the toxic proteins associated with Alzheimer’s.

Before we get into the details, we should mention that some of the authors received funding from the Egg Nutrition Center, “the science and nutrition education division of the American Egg Board.”

Are eggs good for you or bad for you? One hundred years ago, and for thousands of years before that, eggs were considered essential. Nutrient-dense and rich in protein and micronutrients, eggs were a staple throughout the world.

Then, a few decades ago, scientists found that high levels of cholesterol in the blood were a risk factor for heart disease, so high-cholesterol eggs were pushed to the naughty corner.

However, as nutrition science progressed, it became clear that dietary cholesterol did not significantly impact blood levels of cholesterol.

Thanks to this new understanding, and a healthy dose of research funding from the Egg Nutrition Center, eggs were edged slowly back into play.

Their saturated fat content, though, is still a concern, so eggs are still partially sidelined. Still, they are likely much healthier than many of the low-fat, highly processed snacks that have replaced eggs in modern kitchens. In fact, eggs contain all essential trace elements.

Today, most nutritionists and associated experts have a relatively neutral view of eggs. In general, the advice is that they can form a part of a healthy, well-balanced diet, but at the same time, eating multiple eggs per day could be unhealthy.

Alzheimer’s is the most common form of dementia, and despite decades of research, there is no cure, and treatments that can slow the disease are severely lacking.

For that reason, understanding the lifestyle factors associated with increased risk is essential. In this vein, many scientists are focusing on dietary influences.

Previous research has shown that choline is important for cognitive function. It has also identified a potential link between moderate choline intake and a reduced risk of dementia. As the authors of the latest study explain, eggs are the “top food source” of choline, so they are worth investigating. 

Choline has many important functions; for instance, it is a precursor to the neurotransmitter acetylcholine, plays a pivotal role in cell membranes, and has neuroprotective powers. 

Also, as the authors explain, “choline modulates the expression of key genes related to memory, learning, and cognitive functions via epigenetic mechanisms.”

Although our body can synthesise choline, it cannot synthesize enough to meet all the body’s needs, so some must be taken in with our diet. 

Aside from choline, eggs contain essential omega-3 fatty acids, which support brain health as we age. Worryingly, studies show that the majority of adults in the United States do not consume enough of these essential fatty acids.

These facts led the authors of the new study to investigate links between egg consumption and Alzheimer’s risk.