Choline doesn’t get nearly the attention folate or vitamin B12 do, despite playing a similar role in brain health. Two separate long-running studies have now linked low choline intake to a higher risk of dementia and Alzheimer’s disease — and most American adults don’t get enough of it.
Key Takeaways
- Choline is a nutrient found in eggs, meat, fish, and dairy that supports brain cell structure and the production of a key neurotransmitter involved in memory.
- The Framingham Heart Study, following over 3,200 people for an average of 16 years, found that low choline intake was significantly linked to a higher risk of both dementia and Alzheimer’s disease.
- A separate, more recent study of adults averaging 81 years old found the lowest Alzheimer’s risk at a choline intake of about 350 mg per day, with intake above that threshold linked to a 51% lower rate of Alzheimer’s diagnosis compared to the lowest intake group.
- Most American adults fall short of recommended choline intake, particularly women, for whom the recommended adequate intake is 425 mg per day (550 mg for men).
What the Framingham Heart Study Actually Found
Researchers analyzed dietary data from 3,224 participants in the Framingham Offspring Cohort, tracking them for an average of 16 years between 1991 and 2011, during which 247 people developed dementia, 177 of them Alzheimer’s specifically. After adjusting for other factors like age, education, and cardiovascular risk, low choline intake — defined in this study as 219 mg per day or below for dementia risk, and 215 mg per day or below for Alzheimer’s risk — was significantly associated with a higher risk of both conditions. The researchers found the lowest probability of developing dementia at a choline intake around 371 mg per day, and the lowest probability of Alzheimer’s specifically at around 385 mg per day.
A Second, More Recent Study Found a Similar Pattern
A separate study, published in 2025 by researchers including those from George Washington University and Tufts University, looked at a different group entirely: 991 older adults with a mean age of 81.4, enrolled in the Rush Memory and Aging Project in Chicago, followed for an average of nearly 8 years. This study is the actual source of the frequently cited “350 mg per day” figure — its statistical modeling identified that specific intake level as the point of lowest Alzheimer’s risk. Compared to the lowest choline intake group, people consuming more than 350 mg per day had a 51% lower rate of Alzheimer’s diagnosis. The pattern held regardless of participants’ APOE ε4 genetic status, a gene variant strongly linked to Alzheimer’s risk — suggesting choline’s apparent benefit isn’t limited to people without that genetic risk factor.
Why Choline Matters for the Brain
Choline is a building block for acetylcholine, a neurotransmitter directly involved in memory and learning, and it also supports the structural integrity of brain cell membranes. It’s found naturally in eggs (particularly the yolk), meat, fish, poultry, and dairy products, with smaller amounts in some vegetables like broccoli and Brussels sprouts. Despite this, national nutrition survey data has repeatedly shown that most American adults don’t meet the recommended adequate intake — 550 mg per day for men, 425 mg per day for women — making it one of the more commonly under-consumed nutrients in the typical American diet.
What This Research Can and Can’t Tell Us
Both studies are observational — they tracked what people already ate and compared outcomes over time, rather than randomly assigning people to different choline intake levels the way a clinical trial would. That design can show a strong, consistent association, as it did here across two separate, independently conducted cohorts, but it can’t fully prove that low choline intake directly causes dementia risk to rise, since people with different diets may also differ in other health-relevant ways the studies couldn’t fully account for. That said, having two separate long-term studies, in different populations, using different methods, arrive at a similar general conclusion is a meaningfully stronger signal than either study would be alone.
What This Means for You
If your diet is light on eggs, meat, fish, or dairy, it may be worth taking stock of your choline intake, particularly since deficiency is common and the food sources are fairly ordinary and accessible rather than exotic. This isn’t a guarantee against dementia — Alzheimer’s risk involves many overlapping genetic and lifestyle factors — but ensuring adequate choline intake is a low-risk, evidence-backed piece of an overall approach to brain health, and a reasonable topic to bring up with a doctor or dietitian, especially for older adults or anyone with dietary restrictions that limit choline-rich foods.
Sources: Zhu, C., et al. (2022). Is dietary choline intake related to dementia and Alzheimer’s disease risks? Results from the Framingham Heart Study. American Journal of Clinical Nutrition, 116(5), 1201; Karosas, T., Wallace, T.C., et al. (2025). Dietary Choline Intake and Risk of Alzheimer’s Dementia in Older Adults. The Journal of Nutrition; National Institutes of Health, Office of Dietary Supplements, Choline Fact Sheet.