The type of diet is key to enjoying good health. In childhood, the nutrients we ingest contribute to physical and intellectual development, but the correct functioning of the body continues to be associated with the quality of the diet during the rest of life and has a decisive impact on the appearance of various diseases, some as disabling as those that affect cognitive abilities.
A new analysis from the Framingham Heart Study Offspring has now found a link between the consumption of foods with a high inflammatory index and a higher incidence of dementia in older people. Over a 13-year follow-up, higher Dietary Inflammatory Index (DII) scores were linearly related to an increase in all-cause dementia.
The study was carried out by researcher Debora Melo van Lent from UT Health San Antonio and her collaborators, who have also observed that there is a linear relationship between higher scores on the Dietary Inflammatory Index and Alzheimer’s dementia. The results have been published in the journal Alzheimer’s & Dementia and were adjusted taking into account demographic factors, lifestyle and clinical variables.
Western diet versus Mediterranean diet
In their article, the researchers highlight that numerous studies have shown that pro-inflammatory content in the diet is related to chronic systemic inflammation. The most pro-inflammatory components of the Dietary Inflammatory Index – that is, saturated fat, trans fat and total energy intake – are present in the pro-inflammatory content of the so-called ‘Western diet’.
They explain that this type of diet describes dietary patterns in Western societies and has shown an association with higher concentrations of biomarkers of systemic inflammation and risk factors for all causes and dementia due to Alzheimer’s disease and also with related neurodegenerative diseases, while The Mediterranean diet has shown potential to reduce systemic inflammation, be beneficial for cardiometabolic health, and show promise in reducing the risk of all-cause dementia.
Previous studies from the same cohort group had shown that diets with high inflammatory scores are associated with smaller total brain and gray matter volume, as well as larger lateral ventricle size. The new research analyzed data from 1,487 individuals over 60 years of age (with an average age of 69 years, and 53% of whom were women), who did not suffer from dementia at the beginning of the analysis. Approximately 22% of these people carried the APOE4 allele, a genetic risk factor associated with Alzheimer’s disease.
More pro-inflammatory components, such as saturated and trans fats, are characteristics of the Western diet, which has been associated with an increased risk of neurodegenerative diseases
Anti-inflammatory foods and nutrients included alcohol, beta-carotenes, fiber, vitamins (B6, A, C, D and E), and minerals such as magnesium and zinc. Pro-inflammatories included carbohydrates, cholesterol, saturated fat, and total energy intake. The follow-up period had an average duration of 12.8 years, during which 246 participants developed dementia, of which 187 corresponded to Alzheimer’s disease. No significant interactions were found between DII scores and factors such as APOE4, hypertension, type 2 diabetes or cardiovascular diseases.
The authors of the work stated that they found associations between higher pro-inflammatory DII scores and a higher incidence of all-cause dementia and Alzheimer’s dementia and that, compared to the first quartile (that is, the most anti-inflammatory), the fourth DII score quartile (i.e., most pro-inflammatory) was associated with an 84% increase in the incidence of all-cause dementia.
The researchers highlighted that the most pro-inflammatory components of the Dietary Inflammatory Index, such as saturated and trans fats, are characteristics of the Western diet, which has been associated with biomarkers of systemic inflammation and an increased risk of neurodegenerative diseases. For all these reasons, they conclude that their findings suggest that adopting eating patterns with less inflammatory potential could be a promising strategy to reduce the risk of dementia in old age.
