The #1 Food to Limit to Reduce Your Risk of Dementia, According to Dietitians

How to eat to preserve your memory and keep your brain healthy.

an illustration of a head made out of puzzle pieces
Photo:

Getty Images

More than 55 million people have dementia worldwide, with Alzheimer’s disease being the most common form of dementia, contributing to 60% to 70% of dementia cases. Having Alzheimer’s disease means that you have a progressive disorder that causes brain cells to degenerate and die. This leads to a continuous decline in memory, thinking skills and the ability to perform tasks. Unfortunately, as the disease advances, completing daily activities or communicating becomes difficult. 

Several factors can increase the risk of developing dementia (specifically Alzheimer’s disease), with some being completely out of your control. Aging is the most significant factor, with individuals over the age of 65 at a greater risk. Genetics also play a crucial role, with certain genetic mutations linked directly to the disease.

Along with things you can’t change, certain lifestyle factors can decrease the risk of cognitive decline—and your diet is one important piece of the puzzle. One eating pattern that’s designed to help protect against dementia is the MIND diet. “Some of the best foods for brain health are antioxidant-rich wild blueberries, salad greens for B vitamins, salmon for its anti-inflammatory fatty acids, fiber-rich black beans, and walnuts, the best source of plant-based omega-3 ALA among nuts,” says Maggie Moon, M.S., RD, a dietitian and author of The MIND Diet

For those focused on reducing their Alzheimer’s disease risk, along with eating foods that support brain health, certain foods are best limited—and there is one food that tops this list. 

The #1 Food to Limit to Reduce Dementia Risk

Taking steps to reduce dementia risk is one positive step for brain health. While there isn’t one food that will cause dementia, sugary candy tops the list of foods that are recommended to be limited on a brain-healthy diet. 

“Sugary candies are not your brain’s friend,” Moon says. She points to a study that found that eating too much added sugar more than doubled the risk for dementia. “That includes added sugar from candies, as well as other sweets like pastries, sweetened café drinks and sodas,” she says. Researchers think that high blood sugar and insulin levels are risk factors for Alzheimer’s because insulin resistance may also occur in the brain, which may impact memory.

Of course, everything can be eaten in moderation in a healthy, balanced eating plan. “While fine once in a while, research has found that a diet that is consistently high in refined sugar may increase the amyloid plaque buildup in the brain,” says Laura M. Ali, M.S., RDN, a dietitian and author of MIND Diet for Two. These plaques disrupt the communication system in our brain, and scientists have found that people with Alzheimer’s disease tend to have more of these plaques.”

In fact, says Ali, one study found that every 10 grams of sugar a day consumed (equivalent to 2½ teaspoons of sugar or 8 gummy candies) was associated with a 1.3% to 1.4% increased risk of developing Alzheimer’s disease. Those with the highest daily sugar intake had 19% higher odds of developing Alzheimer’s disease.

Other Ways to Reduce Your Risk of Dementia

Limiting sugary candy is no guarantee of aging without dementia, but it is a positive step forward. Along with limiting added sugar in your diet, here are some other ways to reduce your dementia risk:

  • Exercise by participating in both aerobic activity and resistance exercise. Don’t know where to start? These at-home exercises are great for beginners.
  • If you smoke cigarettes, take the first steps to quit. 
  • Limit alcohol intake. If you regularly drink alcohol, try to do so in moderation. Excessive drinking is linked to cognitive decline. Moderate drinking means two drinks or less in a day for men or one drink or less in a day for women.
  • Stay socially engaged. Maintaining social connections builds your cognitive reserve to maintain good brain function with age. 
  • If you have chronic diseases, such as high blood pressure and diabetes, make sure you’re managing these well. Stiffness in arteries and blood vessels can damage the brain. 
  • Include certain foods in your diet. The MIND diet emphasizes foods like whole grains, nuts, berries, vegetables and olive oil, which research shows may help support brain health. “The brain-healthy MIND diet limits foods high in saturated fats and added sugars because both are linked to oxidative stress, inflammation and the brain plaques and tangles associated with Alzheimer’s disease,” says Moon. However, she clarifies that this diet limits—but does not eliminate—fried foods, pastries and sweets, red meat, whole-fat cheese and butter. 

The Bottom Line

Nothing will guarantee living a life free from developing dementia. But certain steps may help reduce your risk, with your dietary choices being one factor. And along with eating brain-healthy foods, limiting your sugary candy intake can help keep you cognitively sharp. Enjoying a small handful of candy corn on Halloween or conversation hearts on Valentine’s Day won’t “cause” dementia. “It’s important to remember that no single food eaten once, or even once in a while, is going to make or break your brain health,” Moon adds.

Was this page helpful?
Sources
EatingWell uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable and trustworthy.
  1. World Health Organization. Dementia.

  2. Alzheimer’s Association. What is Alzheimer’s Disease?

  3. National Institute on Aging. Thinking About Your Risk for Alzheimer’s Disease? Five Questions To Consider.

  4. Agarwal P, Ford CN, Leurgans SE, Beck T, Desai P, Dhana K, Evans DA, Halloway S, Holland TM, Krueger KR, Liu X, Rajan KB, Bennett DA. Dietary Sugar Intake Associated with a Higher Risk of Dementia in Community-Dwelling Older Adults. J Alzheimers Dis. 2023;95(4):1417-1425. doi:10.3233/JAD-230013

  5. Taylor MK, Sullivan DK, Swerdlow RH, Vidoni ED, Morris JK, Mahnken JD, Burns JM. A high-glycemic diet is associated with cerebral amyloid burden in cognitively normal older adults. Am J Clin Nutr. 2017 Dec;106(6):1463-1470. doi:10.3945/ajcn.117.162263

  6. Alzheimer’s Association. Inside the Brain.

  7. U.S. Department of Agriculture. FoodData Central. Candy, gummy.

  8. Liu L, Volpe SL, Ross JA, Grimm JA, Van Bockstaele EJ, Eisen HJ. Dietary sugar intake and risk of Alzheimer's disease in older women. Nutr Neurosci. 2022 Nov;25(11):2302-2313. doi:10.1080/1028415X.2021.1959099

  9. Alzheimer’s Association. Risk Reduction.

  10. Centers for Disease Control and Prevention. Dietary Guidelines for Alcohol.

Related Articles