The more research that comes out, the more we learn that cognitive decline does not have to be an accepted part of aging. Partaking in regular, moderate exercise like walking, getting a good night's sleep, staying social, and completing activities like puzzles can all help keep your brain young. There's also been much discussion about how eating habits affect your risk of dementia and Alzheimer's disease. And now, a new study shows that two popular diet plans can help stave off cognitive decline as you age.
RELATED: These 6 Foods Can Lead to Better Brain Health—But You're Probably Not Eating Them.
Iron buildup in the brain is associated with cognitive decline.
The study, which was recently published in the journal Neurobiology of Aging, concluded that iron accumulation in the brains of older adults "was associated with lower cognitive performance."
"As we age, too much iron can sometimes accumulate in the brain. Past studies have correlated high levels of iron in the brain with neurodegenerative diseases such as Alzheimer’s disease and dementia," explains MedicalNewsToday.
Specifically, the researchers concentrated on non-heme iron, which is found in plant-based foods and can lead to oxidative stress in brain cells as we age. By contrast, heme iron is what you'll find in red meat, poultry, and fish.
According to the American Red Cross, heme is "the form of iron that is most readily absorbed by your body, at an average of 30 percent." You only absorb between two and 10 percent of non-heme iron, but you consume much more of it typically.
However, eating certain foods can lessen brain iron accumulation.
The researchers used MRI-based mapping to determine iron brain accumulation in 72 healthy adults between the ages of 60 and 86. They took a baseline reading at the start of the study and then again between two-and-a-half and three years later to see how diet affected iron buildup.
They found that foods rich in antioxidants, vitamins, iron-chelating nutrients, and polyunsaturated fatty acids can reduce iron accumulation in the brain and protect against cognitive decline.
RELATED: 10 Best Foods and Drinks for Brain Health, According to New Research.
The study recommends the Mediterranean and DASH diets.
According to the study, the Mediterranean and DASH diets "are rich in the nutrients examined here." Though the researchers note that specifically studying these diets' relation to "brain iron accumulation and cognition would be highly beneficial," there has already been data to support the hypothesis.
A Feb. 2024 study published in the journal JAMA Neurology looked at autopsy results from 754 individuals who passed away between 1997 and 2022 and found that both of these diet plans can lower your risk of cognitive decline.
Registered dietitianKimberly Gomer, MS, RD, LD/N, previously told Best Life that the Mediterranean diet consists of foods that "come as nature made them, without extra added sugar, processed seed oils, chemicals, and additives." This includes extra-virgin olive oil, fish high in omega-3 fatty acids such as salmon and mackerel, dark leafy greens, beans and legumes, whole grains, nuts, and berries.
The DASH diet, short for Dietary Approaches to Stop Hypertension, is similar to the Mediterranean diet, but it allows more dairy and meat (mainly poultry) and focuses strongly on reduced sodium intake.
Monique Richard, MS, RDN, LDN, a registered dietitian nutritionist and owner of Nutrition-In-Sight, told MedicalNewsToday that, based on the study results, she would recommended consuming adequate amounts of fresh produce: "For the average adult, three servings of vegetables and two servings of fruit a day from a variety of sources (a reminder that 1/2 cup cooked = a serving and 1 cup raw = a serving) will be beneficial to provide the nutrients and antioxidants that would be helpful."
"Further dietary pattern considerations would be to monitor heme (primarily found in animal products) and non-heme (primarily from plants) sources of iron intake per individual to make sure that the animal sources are not in excess and appropriate as well as a wide variety of non-heme sources are provided," Richard added.
RELATED: Longevity Expert Says Avoid Eating the "Poisonous 5 Ps" If You Want to Live to 100.
The health benefits don't stop there.
Adopting a Mediterranean or DASH diet won't only better your brain health.
The National Institute of Health (NIH) considers the DASH diet the number-one eating plan for heart health, diabetes, and bone and joint health.
For example, a 2017 study published in the Journal of the American College of Cardiology found that following a DASH diet can help people lower their blood pressure by 3-20 points within weeks or months.
A Mediterranean diet has been shown to increase longevity, help maintain a healthy weight, and lower cardiovascular disease risk, among other benefits.
The takeaway.
To reduce the buildup of non-heme iron that can accumulate in our brains as we age and accelerate cognitive decline, research supports adopting a Mediterranean or DASH diet that emphasizes foods rich in antioxidants, iron-chelating nutrients, and polyunsaturated fatty acids. However, more research is needed to study these specific diets as related to iron buildup.
If you're considering changing your diet or are concerned about your cognitive health, always speak to your healthcare provider.
