- New research posits that eating an anti-inflammatory diet may lower the risk of Alzheimer’s disease.
- Data suggest that people can lower their risk even after developing physical changes associated with the disease.
- Many doctors recommend following a Mediterranean diet to lower risk.
Dementia impacts nearly 10% of older adults in the U.S., but scientists still don’t know exactly why some people develop it, and others don’t. Still, research suggests that a mix of genetics and lifestyle factors determines your risk of being diagnosed with the devastating condition, which means you may be able to lower the odds by taking certain steps.
Now, a new study points to a specific dietary pattern that may help lower your risk. The study, published in JAMA Network Open, analyzed data from 1,865 older adults who participated in the Swedish National Study on Aging and Care in Kungsholmen. The participants, who did not have dementia at the start of the study, were followed for up to 15 years.
The researchers analyzed the participants’ diets and health records. After 15 years, 240 of the participants were diagnosed with dementia. But the researchers discovered that people who followed diets with “lower inflammatory potential” had a lower risk of a dementia diagnosis, even when they’d already developed physical changes in the brain that put them at a higher risk. In people with certain biomarkers for Alzheimer’s disease, anti-inflammatory diets reduced risk by up to 29%.
“These findings reinforce the importance of targeted dietary dementia prevention strategies not only for the general population but also for individuals already at elevated risk,” the researchers wrote in the conclusion.
Meet the experts: Anja Mrhar, M.Sc., lead study author and research assistant at Karolinska Institutet; Liron Sinvani, M.D., geriatrician and director of research and innovation at the Northwell Institute of Healthy Aging; Amalia Peterson, M.D., behavioral neurologist and assistant professor of neurology at Vanderbilt University Medical Center.
“Previous research has shown that healthier dietary patterns are associated with better brain health and lower dementia risk. However, dementia-related biological changes can begin many years before symptoms appear, and it has been less clear whether these associations are still relevant once these biological signs of increased risk are already detectable,” says Anja Mrhar, M.Sc., lead study author and research assistant at Karolinska Institutet. The study suggests that diet may help to lower risk, even in people who have changes that raise their odds of developing the disease, she says.
“These findings are incredibly compelling and, frankly, hopeful,” says Liron Sinvani, M.D., a geriatrician and director of research and innovation for the Northwell Institute of Healthy Aging. “What this study shows is that even among people who already have biological signs of Alzheimer disease brewing in their blood—elevated biomarkers reflecting amyloid pathology, nerve cell damage, and brain inflammation—eating a diet with lower inflammatory potential was associated with up to a 29% reduction in dementia risk.”
The study’s findings add to previous research that suggests an anti-inflammatory diet may help to lower the risk of Alzheimer’s disease. Here’s why doctors say the data are worth paying attention to.
Why might this diet help?
It’s important to remember that this study is observational, so it doesn’t prove that an anti-inflammatory diet lowers the risk of Alzheimer’s disease or dementia. Instead, it found a link between eating a low-inflammation diet and having reduced odds of being diagnosed with the disease. Still, there are a few theories on what could be behind this.
“These findings suggest the pathways through which diet influences dementia risk could differ depending on the level of Alzheimer’s dementia pathology in the brain,” says Amalia Peterson, M.D., behavioral neurologist and assistant professor of neurology at Vanderbilt University Medical Center. Having chronic inflammation in the body could increase inflammation in the brain, raising the risk of developing Alzheimer’s disease, she points out.
Dr. Sinvani agrees. “When we eat foods that promote inflammation—think processed meats, refined sugars, and highly-processed foods—we raise levels of inflammatory molecules like interleukin-6 and tumor necrosis factor alpha in the blood,” she says. “Over time, that systemic inflammation can cross into the brain, activating immune cells called microglia and support cells called astrocytes.” That sets off a chain reaction, she explains: More inflammation, more damage to nerve cells, and potentially faster accumulation of the amyloid plaques and tau tangles that define Alzheimer’s disease.
An anti-inflammatory diet, on the other hand, “works to quiet that process,” Dr. Sinvani says. These diets tend to focus on foods like vegetables, fruits, whole grains, fish, nuts, and olive oil, which are rich in antioxidants, polyphenols, omega-3 fatty acids, and B vitamins, she explains. “These compounds help reduce oxidative stress, support healthy blood vessels in the brain, and may even improve the resilience of brain cells in the face of early pathology,” Dr. Sinvani says. “In other words, even if your brain is starting to accumulate Alzheimer’s-related changes, an anti-inflammatory diet may help your brain tolerate those changes longer before symptoms appear.”
What does an anti-dementia diet look like?
The study used three different dietary patterns to evaluate participants’ diets: one that measures adherence to a Mediterranean-style diet, another that assesses general healthy eating, and a third that captures a diet’s inflammatory potential. All three dietary patterns were linked to lower dementia risk, but the associations were “more evident” among those with lower levels of biomarkers associated with dementia. “The lower-inflammatory dietary pattern, however, showed the most consistent associations among people with elevated biomarker levels,” Mrhar says.
“In practical terms, diets with lower-inflammatory potential generally reflect higher intake of items such as vegetables, tea and coffee, and lower intake of items such as red and processed meat, refined grains, and soft drinks,” Mrhar says. She stresses that this shouldn’t be viewed as a checklist of foods to have, but an eating pattern to aim for.
However, Dr. Peterson points out that there is overlap between the eating patterns. “The diets in this study share some similarities such as encouraging the consumption of fruits, nuts, and whole grains and discouraging processed foods and red meat,” she says.
“The key takeaway is that this is not about one magic food or one thing to avoid. It is about an overall pattern of eating,” Dr. Sinvani says.
What to eat if you’re concerned about dementia
Doctors generally suggest following a Mediterranean diet or a similar eating plan. “It has the strongest evidence base for brain health and has been shown in prior research to reduce the risk of developing dementia by approximately 23%,” Dr. Linvani says. “It is also good for your heart, and what is good for your heart is good for your brain.”
Anti-inflammatory foods are also important, per Dr. Linvani. “Load up on colorful fruits and vegetables, leafy greens, fatty fish at least twice a week, nuts, whole grains, and olive oil,” she says. “These foods are packed with nutrients that directly support brain health—omega-3 fatty acids, antioxidants, polyphenols, and B vitamins.”
While you’re at it, Dr. Linvani recommends minimizing ultra-processed foods and added sugars. “These are some of the biggest dietary drivers of chronic inflammation,” she says.
While more research is needed, experts say these findings are a step in the right direction. “Our findings suggest that diet quality—particularly the inflammatory potential of the diet—may remain relevant even among older adults with biological signs of increased dementia risk,” Mrhar says. “At the same time, diet is only one part of dementia prevention. Other lifestyle and health factors, including physical activity, cardiovascular health, sleep, social engagement, and management of chronic conditions, are also important.”
Read the full article here
