There is no cure or proven way to prevent dementia, which affects 55 million people worldwide, but several studies have indicated that following a Spanish Mediterranean diet can reduce the risk of developing the condition. People who adhered more closely to a Mediterranean diet, rich in seafood and plant-based foods, had up to 23% lower risk of dementia than those with less adherence to the diet, according to the latest study published this week in the journal BMC Medicine by an international team of researchers. In absolute terms, the research found that closely following a Mediterranean diet equated to a 0.55% reduction in the risk of developing dementia.
The latest study involved 60,298 people who were part of the UK Biobank study and were tracked over a period of just over nine years. During the study period, there were 882 cases of dementia in the group. The individuals were aged between 40 and 69 and were white British or Irish. How they adhered to the Mediterranean diet was assessed using two different questionnaires that have been widely used in previous diet studies, the researchers said.
WHAT FOODS ARE INCLUDED IN THE MEDITERRANEAN DIET?
The Mediterranean diet has an impressive list of scientific studies behind it. It has been found that this way of eating can prevent cognitive decline, as well as help the heart, reduce diabetes, prevent bone loss, promote weight loss and more.
A study published on 8 March revealed that people who ate foods from the Mediterranean and MIND brain-focused diets had fewer of the characteristic signs of Alzheimer’s, such as beta-amyloid plaques and tau tangles in the brain, when autopsied. Alzheimer’s is a form of dementia. The MIND diet, short for Mediterranean-DASH Diet Intervention for Neurodegenerative Delay.
The Mediterranean diet focuses on plant-based cuisine. The majority of each meal should consist of fruits and vegetables, whole grains, beans and seeds, along with some nuts. There is a strong emphasis on extra virgin olive oil. Butter and other fats are rarely, if ever, consumed. Sweets and products made with refined sugar or flour are rare.
Meat may make a rare appearance but usually only to flavour a dish. Instead, meals may include eggs, dairy products and poultry, but in much smaller portions than in the traditional Western diet. However, fish, which is full of brain-boosting omega-3 fatty acids, is a staple.
Study participants who adhered more closely to the diet were more likely to be female, have a BMI in the healthy range, have a higher level of education and be more physically active than those with a lower adherence to the diet.
David Curtis, honorary professor at the UCL Genetics Institute in London, who was not involved in the research, said the latest study was observational and did not find a causal relationship. The finding may reflect a generally healthier lifestyle, he said.
“It is not clear that a diet in itself reduces the risk of dementia, although it is plausible that it does. It is important to note that the study refers to all forms of dementia, not specifically Alzheimer’s disease. In my opinion, if there is an effect of diet, it is more likely to be on cardiovascular health in general, and therefore to affect dementia due to vascular disease rather than Alzheimer’s disease.
THE MEDITERRANEAN DIET HAS A SOCIAL COMPONENT
Duane Mellor, a registered dietitian and senior lecturer at Aston University in Birmingham, UK, said the benefits of the Mediterranean diet are not limited to the nutrients provided by the food.
“The Mediterranean way of eating is not just about the food on the plate, but the social interactions associated with eating, and people who socialise more have a lower risk of dementia and other conditions,” Mellor, a registered dietitian and senior lecturer at Aston University in Birmingham, UK, who was not involved in the research, said in a statement.
“We need to consider how a Mediterranean-type diet can be adapted to the foods available and consumed in the UK, so that inclusive messages about eating healthily can be developed, including the importance of the social aspects of sharing and eating food with others.”
The study tentatively suggested that adhering to a Mediterranean diet was associated with a lower risk of dementia even when a person had an existing genetic risk for the disease.