A wealth of previous research has linked unhealthy foods like sugary snacks and fried foods to poorer brain health compared to those who opt for healthier options. But a new study, published in the journal Neurology, suggests that the foods you eat together may matter when it comes to your dementia risk.
The researchers asked 1.522 participants to complete a comprehensive dietary survey in 2002, which includes a qualitative food frequency questionnaire. At a follow-up 12 years later, they looked at 209 participants who had developed dementia, as well as 418 people who had not.
They used the data to create "food webs," which identified what types of foods were eaten most in combination, and whether those food groups were substantially different between those with dementia and those without.
The researchers found that people who developed dementia were more likely to eat highly processed meats, such as sausages and sausages, with starchy foods, like potatoes, alcohol and sugary snackssuch as cookies and cakes.
Processed meat seemed very important in the diet, which means that it was associated with many foods. The worst eating habits toward processed meats and snack foods were evident years before the dementia diagnosis. However, diverse and healthy diets appear to decrease the risk of developing dementia.
In other words, it wasn't the processed meat itself that seemed problematic, but the way its consumption was linked to so many other ingredients that are considered less healthy, such as pasta, jam and potatoes. (However, it's worth noting that athletes may benefit from using these foods for fuel when fast-acting carbohydrates and sugars are needed to keep them from sticking through a long workout.)
However, the study has some limitations. In particular, it required the participants to remember what they ate rather than the researchers monitoring their consumption. Also, it didn't track dietary patterns over time, to see if the changes made any difference.
Even with those caveats, the study provides good evidence about the importance of dietary diversity. Diversity is probably protective because it provides a combination of healthy nutrients, including vitamins, polyphenols, and carotenoids from plant foods, as well as good fats and proteins. People who did not develop dementia in the study were more likely to have a lot of diversity in their diets, and that included healthier foods.