A team of scientists has discovered an unexpected relationship between diet and brain health. The study, published in the prestigious journal Neurology, comes from Lund University, and is based on the exhaustive follow-up of almost 28,000 people over a period of up to 25 years. In a world where dietary advice seems to change with the seasons, these findings open a controversial new avenue for exploring how we eat and what consequences that might have for our minds over time.

The study design is ambitious. Detailed questionnaires, food diaries and individual interviews were collected, and intersected with the onset of dementia over the decades. The average age of the participants was around 58 years old when the research began in the 1990s. With scientific patience and a rigorous observational methodology, the researchers analyzed the relationship between the consumption of different types of dairy and the subsequent appearance of cognitive impairment.

Just cheese, no milk

Among the most striking findings, it stands out that those people who consumed at least 50 grams of high-fat cheeses daily (defined as more than 20%, with examples such as cheddar, brie or gouda) showed an approximately 13% lower risk of developing dementia, compared to those who ate less than 15 grams per day. The risk reduction was even more relevant in the case of vascular dementia, reaching up to a 29% reduction among those who consumed greater quantities of these intense cheeses.

In parallel, the consumption of at least 20 grams per day of cream with a high fat content (30-40%) also showed a significant association with a lower incidence of dementia: 16% lower risk compared to those who did not include it in their diet. However, other dairy products such as milk (whole or skimmed), yogurt or butter did not show any statistically significant relationship with the development of cognitive impairment.

There is no clear causality

Although the numbers are intriguing, interpretation of the study requires caution. Emily Sonestedtlead author of the research, insists that the observational nature of the design prevents establishing a direct causal relationship.

That is, it cannot be said with certainty that cheese or cream protect against dementia: simply, a statistical correlation has been identified. It could be that those who consume these products also maintain other healthy habits (such as greater physical activity or a balanced diet in general) that are influencing the result, despite the statistical adjustments made.

Thus, although the study does not invalidate the evidence on the cardiovascular risk of saturated fats in certain contexts, does invite us to reconsider the role of these fatsespecially those from fermented dairy products, within a balanced diet.

Furthermore, the authors propose that the relationship between fatty cheese consumption and lower risk of vascular dementia could be mediated by indirect effects. For example, these foods could contribute to better overall vascular health, which in turn would be reflected in a lower incidence of circulation-related brain problems. But it is not ruled out that there are other mechanisms not yet fully understood..

Of course, these results should not be taken as a license to launch unreservedly into a diet rich in saturated fats. What this work highlights is that not all fats are equal, nor are all metabolic, social and dietary contexts comparable. In the long conversation between science and nutrition, This Swedish studio introduces a new voice worth listening to.