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Eggs have spent decades bouncing between dietary hero and villain, praised for their protein one year and vilified for their cholesterol the next. A new study may tip the scales again. Researchers who tracked nearly 40,000 older adults for more than 15 years found that people who ate eggs regularly were far less likely to be diagnosed with Alzheimer’s disease than those who never or rarely touched them. The most frequent egg eaters, those having five or more servings a week, showed a 27% lower risk.
Alzheimer’s diseasecasts a long shadow over American life. It is the sixth leading cause of death in the United States, and the national costs of managing the disease are projected to exceed $600 billion annually by 2050. During the same period, the share of Americans aged 65 and older is expected to roughly double, from about 10% to 20%. With no cure available and current drug treatments offering limited help, researchers have turned increasing attention to prevention, and specifically towhat people eat.
The study, published inThe Journal of Nutrition, drew on data from the Adventist Health Study-2, a long-running research project that enrolled more than 96,000 members of the Seventh-day Adventist church across all 50 states between 2002 and 2007. That population is especially useful for studying diet because Adventists have a wide range of eating habits, from strict vegans who never touch an egg to omnivores who eat them daily. By linking participants’ dietary records with Medicare claims data, researchers could track who eventually received a clinical Alzheimer’s diagnosis through the medical system rather than relying on self-reported memory problems.
Participants filled out a detailed food questionnaire at enrollment covering more than 200 food items, including how often they ate visible eggs: boiled, scrambled, fried, in omelets, and so on. Researchers sorted participants into five groups based on egg frequency: never or rarely, one to three times per month, once per week, two to four times per week, and five or more times per week. A separate calculation also estimated totaldaily egg intakein grams, capturing eggs hidden in baked goods, mixed dishes, and recipes.
After applying strict eligibility requirements, including beingat least 65, enrolled in traditionalMedicare, and free of an Alzheimer’s diagnosis at the start, the final sample included 39,498 people. Their average age at enrollment was 64, about 64% were female, roughly 74% were non-Hispanic White, and 19% were Black. The average follow-up period was 15.3 years, covering more than 603,000 person-years of observation. During that time, 2,858 participants received a clinical Alzheimer’s diagnosis through Medicare records.
Researchers built statistical models that progressively accounted for a long list of factors that could muddy the results: age, sex, race, education, marital status, body weight, physical activity, sleep, smoking history, alcohol use, intake of other major food groups, total calorie intake, and pre-existing health conditions includingheart disease, high blood pressure,high cholesterol, respiratory conditions, anemia, kidney disease, thyroid problems, and cancers.
Even after adjusting for all of those variables, the pattern was clear. Compared to people who never or rarely ate eggs, those who consumed them just one to three times per month had a 17% lower risk of Alzheimer’s.Eating eggsonce a week was associated with a 17% reduction as well. Two to four times per week corresponded to a 20% lower risk, and five or more times per week was linked to a 27% lower risk. Statistical tests confirmed the trend was real.
A separate analysis modeled egg intake as a continuous daily measure rather than sorting people into groups. Using roughly one large egg per week as the reference point, the model found that people who ate zero eggs hada 22% higher riskof Alzheimer’s disease. Because this was an observational study and not a controlled experiment, that finding cannot prove cause and effect, but it does flip the usual framing: rather than eggs simply helping, skipping them altogether may carry its own penalty.
The results also held up under several checks designed to test their reliability. When the researchers removed all vegans from the analysis — sincevegans made upa large chunk of the zero-egg group and tend to differ from others in many lifestyle ways — the findings barely budged. The team also ran substitution analyses, asking what would happen statistically if participants swapped their eggs for equivalent portions of nuts, seeds, or beans. The egg-eating groups still showed lower Alzheimer’s risk, a result that points to something specific about eggs rather than simply eating more protein-rich foods in general.
Source: Drudge Report
