Prevent Cognitive Decline with a Mediterranean Eating Pattern
By Lisa Andrews, MED, RD, LD
Did you know that the risk of several chronic, degenerative diseases may be reduced by adopting a Mediterranean diet? A Mediterranean diet is based on the eating habits of populations that border the Mediterranean Sea. It encompasses cuisine from over 20 countries, including Spain, France, Italy, and Greece.
This eating pattern is rich in fruits, vegetables, nuts, seeds, legumes, low-fat dairy, and whole grains, while staying low in sugar, red meat, and processed foods. Although the cuisines vary, they share many of the same principles.
As of 2018, more than 5 million Americans have Alzheimer’s disease according to experts. Brain changes associated with Alzheimer’s can occur decades before symptoms are seen. Researchers are saying that following a Mediterranean diet for an extended period, rather than a standard Western diet, may result in up to a three-and-a-half-year delay in the progression of Alzheimer’s.
Specific Diet Varies Among Regions
The tricky thing is that there is no single Mediterranean eating pattern. Components of the diet may vary depending on the region and population. In addition, connections between individual aspects of the Mediterranean diet and specific aspects of mental performance have not been frequently studied.
Analysis of Greek Population
Costas Anastasiou and his team used a cohort population in Greece to assess the association of compliance to a Mediterranean eating plan with dementia and certain aspects of cognitive function. Subjects who participated in the Hellenic Longitudinal Investigation of Aging and Diet (an ongoing population-based study identifying possible links between diet and cognitive function in a sample representative of the Greek regions) were part of the analysis.
A full clinical and neurological evaluation for the diagnosis of dementia was used and cognitive performance was evaluated according to five cognitive domains (language, memory, attention-speed, executive functioning, and visuospatial perception) and a composite cognitive score. An a priori score based on a detailed food frequency questionnaire was used to assess adherence to the Mediterranean diet.
Of 1,865 subjects (mean age 73 +/- 6 years, 41% male), 90 were confirmed to have dementia while 223 had mild cognitive impairment. A 10% decrease in the odds for dementia was seen with each unit increase in the Mediterranean dietary score.
Following a Mediterranean eating pattern was also linked with better performance in memory, language, visuospatial perception and the composite cognitive score. The associations for memory were strongest. Fish intake was negatively associated with dementia and cognitive performance was positively associated with non-processed cereal intake.
What fascinating results! Finally a diet that can help prevent cognitive decline.
Tenets of the Mediterranean Diet:
An overall plant-based diet with increased intake of a variety of fruits and vegetables.
Heart-healthy fats such as olive oil, avocado, nuts, and seeds.
Lean protein, including fish a few times per week. Adding legumes to meals as well.
Whole grains such as bulgur, whole wheat couscous, oatmeal, and quinoa.
Minimal red meat, sugar, alcohol, and dairy.
Healthy fats are an important part of the Mediterranean diet. Less healthy fats, such as saturated and trans fats, contribute to heart disease. Olive oil is the most often-used fat in the Mediterranean diet. Olive oil lowers total cholesterol and low-density lipoprotein cholesterol levels.
Fish such as mackerel, herring, sardines, albacore tuna, salmon and lake trout are rich in omega-3 fatty acids. This polyunsaturated fat may reduce inflammation in the body. Omega-3 fatty acids also help decrease triglycerides, reduce blood clotting, and decrease the risk of stroke and heart failure.
There have been studies showing that people who follow a Mediterranean diet closely are less likely to have Alzheimer's disease than people who don't. Research suggests a Mediterranean diet may slow cognitive decline in older adults. The risk of mild cognitive impairment may be reduced. Mild cognitive impairment is a stage between the cognitive decline that occurs as a normal part of aging and the memory problems caused by dementia or Alzheimer's disease.
It may be the high levels of antioxidants from the fruit and vegetable part of the diet that may help to protect the brain. There may also be a beneficial link between the lower levels of cholesterol associated with the Mediterranean diet and memory and thinking problems.
Following a Mediterranean diet may reduce the risk that mild cognitive impairment will progress into Alzheimer's.
In a study by Dr. Lisa Mosconi from Weill Cornell Medicine that was supported by the NIH’s National Institute on Aging (NIA), differences were seen in the brains of those who followed the Mediterranean diet versus those who followed a Western diet. At the start of the study, people on the Western diet had more protein deposits than those on the Mediterranean diet. This particular protein builds up in the brains of people with Alzheimer’s. During follow-up brain scans, even more deposits showed up for those on the Western diet. Dr. Mosconi said, “We’re seeing these changes only in parts of the brain specifically affected by Alzheimer’s, and in relatively young adults. It all points to the way we eat putting us at risk for Alzheimer’s down the line. If your diet isn’t balanced, you really need to make an effort to fix it, if not for your body, then for your brain.”
So, which elements of the Mediterranean diet protect brain function? There is speculation that healthier food choices may improve cholesterol and blood sugar levels and overall blood vessel health. This may then reduce the risk of mild cognitive impairment or Alzheimer's disease. Some research shows that eating a moderate amount of seafood resulted in a lower number of Alzheimer's-related changes in the brains of people with the gene that increases the risk of developing Alzheimer's.
More research needs to be done to explain links between a Mediterranean diet and reduction of the risk of Alzheimer's disease. Eating a healthy diet remains important in staying physically and mentally fit.
This information is for educational purposes only. The statements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease. Consult your physician if you have any question regarding a medical condition
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Costas A. Anastasiou, Mary Yannakoulia,, Mary H. Kosmidis,Efthimios Dardiotis, Giorgos M. Hadjigeorgiou, Paraskevi Sakka,, Xanthi Arampatzi, Anastasia Bougea, Ioannis Labropoulos,Nikolaos Scarmeas. Mediterranean diet and cognitive health: Initial results from the Hellenic Longitudinal Investigation of Ageing and Diet. August 1, 201, https://doi.org/10.1371/journal.pone.0182048