Alzheimer’s disease and other forms of dementia are becoming more common as people live longer. These conditions affect memory, thinking, and daily life, and they place a heavy burden on families and healthcare systems.
Because there is still no cure, many researchers are focusing on ways to reduce the risk of developing these diseases. One important area of research is diet, since what we eat every day can have long-term effects on our brain health.
A large study published in the journal Neurology has now found that not all plant-based diets are the same when it comes to protecting the brain. The researchers showed that eating a high-quality plant-based diet is linked to a lower risk of Alzheimer’s disease and other dementias, while eating a low-quality plant-based diet may actually increase the risk.
Plant-based diets are often seen as healthy, but this study makes it clear that the type of plant foods matters. A general plant-based diet simply means eating more foods from plants and fewer from animals such as meat, dairy, and eggs.
However, this does not always mean the diet is healthy. For example, foods like white bread, sugary drinks, and processed snacks can also be plant-based but are not good for health.
To better understand this, the researchers divided plant-based diets into three types. The first was the overall plant-based diet, which focused on eating more plant foods without considering their quality.
The second was a healthful plant-based diet, which included foods like whole grains, fruits, vegetables, nuts, beans, and healthy oils. The third was an unhealthful plant-based diet, which included refined grains, sugary foods, fruit juices, and foods high in added sugars.
The study followed 92,849 people with an average age of 59 over about 11 years. The participants came from different backgrounds, including African American, Japanese American, Latino, Native Hawaiian, and white groups. During the study period, more than 21,000 people developed dementia.
At the beginning, participants filled out detailed food questionnaires. Based on their answers, researchers gave each person scores for how closely their diet matched each type of plant-based diet. The participants were then grouped into levels based on these scores.
The results showed clear patterns. People who ate more plant foods overall had a slightly lower risk of dementia. However, the biggest benefit was seen in those who followed a healthful plant-based diet. These individuals had a 7 percent lower risk compared to those who ate the least healthy plant foods.
In contrast, people who followed an unhealthful plant-based diet had a higher risk. Those who consumed the most low-quality plant foods had a 6 percent higher risk of developing dementia.
The study also looked at how changes in diet over time affected risk. In a smaller group of participants who updated their diet after 10 years, the findings were even more striking.
People who moved toward an unhealthy diet had a 25 percent higher risk of dementia. On the other hand, those who improved their diet and reduced unhealthy plant foods had an 11 percent lower risk.
These findings suggest that improving diet quality, even later in life, can still make a difference. It is not too late to make healthier choices.
In analysing the study, it is important to note that it shows a link, not a direct cause. This means the results do not prove that a healthy plant-based diet prevents dementia, but they strongly suggest it may play an important role. Another limitation is that the data relied on self-reported food questionnaires, which may not always be completely accurate.
Despite these limitations, the study provides valuable insight. It highlights that simply eating plant-based foods is not enough. The quality of those foods matters greatly. Whole, minimally processed foods appear to support brain health, while sugary and refined foods may do the opposite.
Overall, this research adds to growing evidence that diet is an important factor in brain health. It suggests that choosing healthier plant foods could be a simple and practical way to reduce the risk of dementia over time.
If you care about brain health, please read studies about how the Mediterranean diet could protect your brain health, and Omega-3 fats and carotenoid supplements could improve memory.
For more health information, please see recent studies about antioxidants that could help reduce dementia risk, and higher magnesium intake could help benefit brain health.
Source: University of Hawaii at Manoa.
